WO2021037011A1

WO2021037011A1 - Device and method for wireless communication system, and storage medium

Info

Publication number: WO2021037011A1
Application number: PCT/CN2020/110951
Authority: WO
Inventors: 赵培尧; 王昭诚; 曹建飞
Original assignee: 索尼公司; 赵培尧
Priority date: 2019-08-28
Filing date: 2020-08-25
Publication date: 2021-03-04
Also published as: CN114270940A; CN112449383A

Abstract

The present invention relates to a device and method for a wireless communication system, and a storage medium. In the embodiments of the present disclosure, a representative terminal device is selected from a plurality of terminal devices in a terminal device group, such that the terminal device group can be switched to a target cell from an original cell in the unit of group with the representative terminal device being a representative of the terminal device group.

Description

Device, method and storage medium for wireless communication system

Technical field

The present invention generally relates to wireless communication systems, and particularly relates to cell handover technology in wireless communication systems.

Background technique

With the development of science and technology and the advancement of technology, people's demand for travel is increasing day by day. More and more passengers and their equipment on transportation have brought a lot of demand for communication services. Therefore, it is very important to study the wireless communication system on transportation, especially high-speed transportation.

Because high-speed vehicles move faster, users on high-speed vehicles face frequent handoffs between cells. In addition, there are a large number of passengers in high-speed transportation, and there are often a large number of users who need to complete the handover in a short time. Therefore, for wireless communication on high-speed vehicles, frequent cell switching and simultaneous switching of a large number of users have brought technical challenges that cannot be ignored to the existing wireless communication system. Therefore, research on the technology of fast cell handover and simultaneous handover of a large number of users is of great significance for wireless communication systems on high-speed vehicles.

Summary of the invention

In view of the above situation, the present disclosure proposes a packet-based cell handover technology. In addition, the present disclosure also proposes a technique for cell handover based on prediction.

The present disclosure provides devices, methods, and storage media for wireless communication systems.

An aspect of the present disclosure relates to an electronic device used on the control device side of a wireless communication system. According to one embodiment, the electronic device includes a processing circuit configured to select a representative terminal device from a plurality of terminal devices in the terminal device group, so that the terminal device group can use the representative terminal device as a terminal device The representative of the group switches from the original cell to the target cell served by the electronic device in a group unit.

Another aspect of the present disclosure relates to a terminal device used on the terminal side of a wireless communication system. According to one embodiment, the terminal device includes a processing circuit configured to trigger an electronic device on the control side of a wireless communication system serving the terminal device to send a cell handover request for a terminal device group including the terminal device and receive the corresponding The cell handover response of the terminal equipment group of the terminal equipment group makes the terminal equipment group use one of the terminal equipment as the representative terminal equipment to switch from the original cell served by the electronic equipment to the target cell in a group unit.

Another aspect of the present disclosure relates to an electronic device for the control side of a wireless communication system. According to one embodiment, the electronic device includes a processing circuit configured to: send a cell handover request of the terminal device group to another electronic device in the target cell and receive the cell handover of the terminal device group from the other electronic device In reply, the terminal device group uses one of the terminal devices as the representative terminal device to switch from the original cell served by the electronic device to the target cell in a group unit.

Another aspect of the present disclosure relates to a packet-based cell handover method used in an electronic device on the control device side of a wireless communication system. According to one embodiment, the method includes: selecting a representative terminal device from a plurality of terminal devices in the terminal device group, so that the terminal device group can use the representative terminal device as a representative of the terminal device group, and re-establish it on a group basis. The cell is switched to the target cell served by the electronic device.

Another aspect of the present disclosure relates to a packet-based cell handover method used in a terminal device on the terminal side of a wireless communication system. According to one embodiment, the method includes: triggering an electronic device on the control side of a wireless communication system serving a terminal device to send a cell handover request for a terminal device group including the terminal device and receive a cell handover response for a corresponding terminal device group, so that The terminal device group uses one of the terminal devices as a representative terminal device, and switches from the original cell served by the electronic device to the target cell in a group unit.

Another aspect of the present disclosure relates to a packet-based cell handover method used in an electronic device used on the control side of a wireless communication system. According to one embodiment, the method includes: sending a cell handover request of the terminal device group to another electronic device in the target cell and receiving the cell handover response of the terminal device group from the other electronic device, so that the terminal device group is The terminal device, as a representative terminal device, switches from the original cell served by the electronic device to the target cell in a group unit.

Another aspect of the present disclosure relates to a non-transitory computer-readable storage medium storing instructions that, when executed by a processor, enable the processor to perform the method described in the present disclosure.

Another aspect of the present disclosure relates to a device including a processor and a non-transitory computer-readable storage medium storing instructions. When the instructions are executed by the processor, the device can execute the device described in the present disclosure. method.

Another aspect of the present disclosure relates to an apparatus including components for performing the method described in the present disclosure.

As a result, the present disclosure can simultaneously perform cell switching for users on high-speed vehicles in the form of a group, thereby improving the switching speed, significantly reducing resource overhead, and reducing the probability of random access conflicts when a large number of users perform cell switching at the same time, thereby reducing Handover delay. Moreover, the present disclosure can also trigger cell handover in advance by predicting the received signal quality of the target cell, thereby effectively reducing the probability of handover failure.

The above summary is provided to summarize some exemplary embodiments to provide a basic understanding of various aspects of the subject matter described herein. Therefore, the above-mentioned features are merely examples and should not be construed as narrowing the scope or spirit of the subject matter described herein in any way. Other features, aspects, and advantages of the subject matter described herein will become apparent from the following specific embodiments described in conjunction with the accompanying drawings.

Description of the drawings

A better understanding of the present disclosure can be obtained when the following detailed description of the embodiments is considered in conjunction with the accompanying drawings. The same or similar reference numerals are used in the various drawings to denote the same or similar components. The drawings together with the following detailed description are included in the specification and form a part of the specification, and are used to exemplify the embodiments of the present disclosure and explain the principles and advantages of the present disclosure. among them:

Figure 1 is a flowchart schematically showing a traditional cell handover procedure;

FIG. 2A is a diagram schematically showing a scene in which a high-speed vehicle according to an embodiment of the present disclosure is operated;

FIG. 2B is a diagram schematically showing a cell handover history according to an embodiment of the present disclosure;

FIG. 3 is a block diagram schematically showing an example structure of an electronic device according to an embodiment of the present disclosure;

FIG. 4 schematically shows a flowchart of the operation of an electronic device according to an embodiment of the present disclosure;

Fig. 5 is a flowchart schematically showing a grouping of terminal devices according to an embodiment of the present disclosure;

FIG. 6 is a diagram schematically showing the data format of a cell handover request and a cell handover reply of a terminal device group according to an embodiment of the present disclosure;

FIG. 7 is a diagram schematically showing a random access process of grouped users according to an embodiment of the present disclosure;

FIG. 8A is a diagram schematically showing the time change of the reference signal received power RSRP of the original cell and the target cell of the terminal device; FIG.

FIG. 8B is a diagram schematically showing a cell handover based on prediction according to an embodiment of the present disclosure;

FIG. 9 is an exemplary signaling flowchart schematically showing a packet-based cell handover scheme according to an embodiment of the present disclosure;

FIG. 10 is a schematic diagram schematically showing a cell handover using a subset of downlink transmission beams corresponding to a handover area according to an embodiment of the present disclosure;

FIG. 11 is a block diagram schematically showing an example structure of a terminal device according to an embodiment of the present disclosure;

FIG. 12 is a flowchart schematically showing the operation of a terminal device according to an embodiment of the present disclosure;

FIG. 13 is a block diagram schematically showing an example structure of another electronic device according to an embodiment of the present disclosure;

FIG. 14 is a flowchart schematically showing the operation of another electronic device according to an embodiment of the present disclosure;

15 is a block diagram schematically showing an example structure of a personal computer of an information processing device that can be employed in an embodiment of the present disclosure;

FIG. 16 is a block diagram showing a first example of a schematic configuration of an eNB to which the technology of the present disclosure can be applied;

FIG. 17 is a block diagram showing a second example of a schematic configuration of an eNB to which the technology of the present disclosure can be applied;

FIG. 18 is a block diagram showing an example of a schematic configuration of a smart phone to which the technology of the present disclosure can be applied; and

FIG. 19 is a block diagram showing an example of a schematic configuration of a car navigation device to which the technology of the present disclosure can be applied.

Although the embodiments described in the present disclosure may be susceptible to various modifications and alternative forms, specific embodiments thereof are shown as examples in the drawings and described in detail herein. However, it should be understood that the drawings and detailed description are not intended to limit the embodiments to the specific forms disclosed, but on the contrary, the purpose is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the claims. Program.

detailed description

The following describes representative applications of various aspects such as the device and method according to the present disclosure. The description of these examples is only for adding context and helping to understand the described embodiments. Therefore, it is clear to those skilled in the art that the embodiments described below can be implemented without some or all of the specific details. In other cases, well-known process steps are not described in detail to avoid unnecessarily obscuring the described embodiments. Other applications are also possible, and the solution of the present disclosure is not limited to these examples.

Hereinafter, one or more preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In this specification and the drawings, the same reference numerals are used to denote structural elements having substantially the same function and structure, and repeated descriptions of these structural elements are omitted.

Moreover, in this specification and the drawings, elements having substantially the same function and structure may be distinguished by different letters appended to the same symbol in some cases. On the other hand, when each of a plurality of elements having substantially the same function and structure is not particularly distinguished, only the same symbol will be given.

Typically, a wireless communication system includes at least a control side and a terminal side, and a device on the control side can provide communication services for one or more devices on the terminal side.

In this disclosure, the "control side" of the wireless communication system has the full breadth of its usual meaning, and generally indicates the side in the communication system that transmits signal flow for control, for example, it may be the side in the communication system that controls cell switching. Similarly, the term "terminal side" has the full breadth of its usual meaning, and accordingly can indicate the side in the communication system that receives the signal flow to operate according to control, for example, it can be a part of the communication system that is controlled to perform cell handover. side. As an example, depending on the direction of signal flow in the communication system, "control side" and "terminal side" may include different devices in the communication system. For example, for uplink signal transmission, the equipment on the "control side" may include the "base station" in the communication system, and the equipment on the "terminal side" may correspondingly include the "terminal equipment" in the communication system. Conversely, for downlink signal transmission, the equipment on the "control side" may include the "terminal equipment" in the communication system, and the equipment on the "terminal side" may correspondingly include the "base station" in the communication system.

In this disclosure, the term "base station" has the full breadth of its usual meaning, and includes at least a wireless communication station that is a wireless communication system or a part of a radio system to facilitate communication. As an example, the base station may be an eNB that conforms to the 4G communication standard, a gNB that conforms to the 5G communication standard, a remote radio head, a wireless access point, a drone control tower, or a communication device that performs similar functions.

In the present disclosure, "electronic equipment on the control side" has the full breadth of its usual meaning, and may include, for example, equipment that is a part of a wireless communication system or a radio system to facilitate cell switching. In the present disclosure, “electronic equipment on the control side” and “base station” may be used interchangeably, or “electronic equipment on the control side” may be implemented as a part of the “base station”.

In this disclosure, "mobile management unit" is a device on the control side of a wireless communication system, and the term "mobile management unit" has the full breadth of its usual meaning, for example, it can include being a part of a wireless communication system or a radio system to facilitate Signaling processing and mobility management equipment.

In this disclosure, the term "terminal equipment" or "user equipment (UE)" has the full breadth of its usual meaning, and includes at least terminal equipment that is a part of a wireless communication system or a radio system to facilitate communication. As an example, the terminal device may be a terminal device such as a mobile phone, a laptop computer, a tablet computer, an in-vehicle communication device, etc., or an element thereof. In the present disclosure, "terminal device" and "user equipment" (hereinafter may be simply referred to as "user") can be used interchangeably, or "terminal device" can be implemented as a part of "user equipment".

It should be noted that although the following descriptions of the embodiments of the present disclosure are mainly based on a communication system including a base station and a user equipment, these descriptions can be extended accordingly to include any other types of communication systems on the control device side and the terminal device side. For example, in the case of the downlink, the operation on the control device side may correspond to the operation of the base station, and the operation on the terminal side may correspond to the operation of the terminal device accordingly.

In addition, the description will be made in the following order.

1. Overview of cell handover

2. Examples of wireless communication systems

3. The structural configuration and operation of the equipment

3.1. Structural configuration and operation of electronic equipment in the target cell

3.2. Structure configuration and operation of terminal equipment

3.3. The structural configuration and operation of the electronic equipment in the original cell

4. Application example

5 Conclusion

<<1. Overview of cell handover>>

With the increase in people's travel demand and technological advancement, high-speed transportation, such as high-speed trains and subways, are increasing. More and more passengers and their equipment on high-speed vehicles have brought a lot of demand for communication services, but also brought many problems and challenges.

As high-speed vehicles move faster, users on them face frequent cell handovers. In the prior art, users often perform cell handover in their own unit. The following will introduce an example of a traditional cell handover procedure with reference to FIG. 1.

Fig. 1 is a flowchart schematically showing a conventional cell handover procedure. As shown in FIG. 1, the wireless communication system includes an electronic device 10 in a target cell, a terminal device 20, and an electronic device 30 in the original cell.

In the traditional cell handover process, in step S101, the electronic device 30 serving the user in the original cell performs measurement control on the user's terminal device 20 (for example, Reference Signal Receiving Power (RSRP) measurement control) . Next, in step S102, the terminal device 20 performs measurement based on the control of the electronic device 30, and reports the measurement result to the electronic device 30. Next, when the measurement result meets the cell switching condition, in step S103, the electronic device 30 sends a cell switching request to the electronic device 10 that will serve the terminal device 20 in the target cell to be switched to. Next, in step S104, the electronic device 10 controls whether to permit cell switching. Then, in a case where the cell handover is permitted, the electronic device 10 sends a cell handover reply to the electronic device 30 in step S105. Then, in step S106, the electronic device 30 sends a handover command to the terminal device 20 after receiving the cell handover response.

Subsequently, in step S107, the terminal device 20 will cut off the connection with the electronic device 30 in the original cell, and then perform downlink synchronization with the target cell, and in step S108, use non-competitive random access resources to perform random access to the target cell. Access. Specifically, in downlink synchronization, the terminal device 20 detects a synchronization signal block (Synchronization Signal Block, SSB) to obtain an optimal downlink transmission beam. Then, according to the correspondence between the downlink transmission beam and the uplink random access resource, the terminal device 20 performs random access on the corresponding uplink random access resource, and the electronic device 10 in the target cell detects the optimal uplink reception beam and uses The corresponding relationship between the downlink transmission beam and the uplink random access resource obtains the optimal downlink transmission beam.

The user’s cell handover usually uses non-competitive random access, in which the configuration information of the non-competitive random access resource is sent by the electronic device 10 of the target cell to the electronic device 30 of the original cell through a cell handover reply, and then sent to the electronic device 30 through a handover command Terminal equipment 20.

Next, after the random access is successful, in step S109, the electronic device 10 sends a random access response (Random Access Response, RAR) to the terminal device 20. Finally, in step S110, the terminal device 20 that has successfully detected the RAR sends a handover completion signaling to the electronic device 10 serving the terminal device 20 in the target cell, and since then a cell handover of the terminal device 20 is completed.

However, in the case of high-speed vehicles, the traditional cell handover will have a big problem. As an example, suppose that a high-speed vehicle runs at a moving speed of about 350km/h and a cell radius is 500m. The average residence time of the high-speed vehicle in each cell is only 5s to 10s, so frequent cell switching is required . In addition, there are a large number of passengers in high-speed transportation, so there will be a large number of users who need to complete the handover in a short time. Still taking the 350km/h moving speed as an example, assuming that 85 people can be accommodated every 25m on a high-speed vehicle, there are at most more than 300 users who need to switch between cells within 1s.

The user cell handover on such high-speed vehicles will bring the following problems:

First, a large number of users performing cell handover at the same time will increase the handover preparation time, which may lead to handover failure. In particular, the handover preparation time may correspond to the time from the sending of the cell handover request in step S103 to the sending of the cell handover response in step S105. In the case of a large number of users switching at the same time, the control-side electronic device must process multiple users one by one to prepare for switching, which will inevitably lead to an increase in preparation time. If the preparation time is too long, some users may even be unable to switch. .

Second, a large number of users performing cell switching at the same time will cause insufficient non-competitive random access channel resources to be allocated to users when accessing the target cell, which will cause some users to perform competitive random access, which will cause random access. Increased delay of collision and cell handover;

Third, the handover request and handover response in the existing NR/LTE system are generated separately for each user performing cell handover. When a large number of users perform cell handover at the same time, it will cause information on the Xn/X2 interface between base stations. Increase the cost;

Fourth, cell handover is triggered by a measurement report (for example, RSRP measurement report), and there is a certain time interval (ie, time-to-trigger (TTT)) between the measurement report and the measurement event performed under measurement control. , Due to the fast moving speed of high-speed vehicles, the existence of the trigger time may cause the user to fail to receive the handover command, which will lead to the failure of the cell handover. In particular, the measurement event is triggered. After the trigger time and the handover preparation time between the original cell and the target cell, the original cell sends a handover command to the user. Because the user on the high-speed vehicle moves fast, the RSRP of the user’s original cell may have been Reduce to the extent that the user cannot receive the handover command correctly, which in turn leads to the handover failure.

In view of the above considerations, the present disclosure proposes a technology for packet-based cell handover. In particular, in the technology of the present disclosure, users on high-speed vehicles are simultaneously switched on a group basis, and a representative user in each group is selected for random access, thereby increasing the switching speed and significantly reducing resource overhead. And it reduces the probability of random access conflicts when a large number of users perform cell handover at the same time, thereby reducing handover delay.

Further, the present disclosure also proposes a technology for cell handover based on prediction. In particular, in the technology of the present disclosure, cell handover can also be triggered in advance based on prediction, thereby effectively reducing the probability of handover failure.

The technical implementation of the present disclosure will be exemplarily described below for application scenarios of high-speed trains. However, it should be pointed out that the technical implementation of the present disclosure is not limited to this, and it can also be applied to other types of vehicles that carry multiple terminal devices, where the multiple terminal devices need to be switched frequently and/or simultaneously, such as Scenes of subways, fleets, etc. and Internet of Vehicles scenes, etc. Hereinafter, the electronic device 10, the terminal device 20, and the electronic device 30 may operate according to the radio access technology in LTE of 4G, and may also operate according to the new radio access (NR) technology of 5G.

<<2. Example of wireless communication system>>

Hereinafter, a scene in which a high-speed vehicle operates and a method of identifying a user as a user on a high-speed vehicle according to an embodiment of the present disclosure will be described with reference to FIGS. 2A and 2B.

It is worth pointing out that the solution proposed in the present disclosure is suitable for users on high-speed vehicles with fast moving speeds, fixed trajectories, and a large number of users in similar locations. As shown in FIG. 2A, a high-speed vehicle may travel along a specific track, for example, and a plurality of cell base stations C1-C7 are arranged along the track. During the travel of the high-speed vehicle along a specific track, the terminal equipment of the user carried by the high-speed vehicle will continuously switch from one base station to another base station.

According to the present disclosure, a variety of ways can be used to identify whether the user is a user on a high-speed vehicle. According to one embodiment, users can be identified based on user-related trajectories. As an example, when the user's movement trajectory matches the track of a high-speed vehicle, it is determined that the user is a user on a high-speed vehicle (for example, a high-speed train, a high-speed rail). According to another embodiment, the user may be identified based on the user's speed. As an example, when the user's moving speed is greater than a certain threshold, it is determined that the user is a user on a running high-speed vehicle. According to still another embodiment, it may be determined whether the user is a user on a high-speed vehicle based on both the trajectory and speed of the user. As an example, when the user's movement trajectory matches the trajectory of a high-speed vehicle and the user's speed is high enough, it is determined that the user is a user on a high-speed vehicle.

According to an embodiment, the cell handover history record of the user may be stored to be used to identify the user on the high-speed vehicle. Generally, user mobility can be managed by a mobility management unit (Mobility Management Entity, MME) on the network side. Specifically, as shown in Figure 2B, the MME is made to record the user’s cell handover history, including the cell ID of each cell accessed (for example, C1- _CN ), and the time of access to each cell (also called entering Time, such as T ₁₁ -T _N1 ) and the time of disconnection from each cell (also referred to as leave time, such as T ₁₂ -T _N2 ). According to this embodiment, the entry time may be based on the time when the base station serving the cell receives the handover completion signaling sent by the user, and the leave time may be based on the time when the base station sends the handover command.

Taking a high-speed train as an example, for trajectory-based identification, the network side (for example, MME) pre-stores information of cell base stations along the high-speed train track, including, for example, the ID and location of the base station. By matching the user's cell handover history and pre-stored cell base station information, it is determined whether the user is a high-speed rail user. For example, if the base stations involved in the user's cell handover history are all pre-stored base stations along the high-speed train track, it can be preliminarily determined that the user is moving along the high-speed train track.

Further, for speed-based identification, the MME can estimate the average speed of the user's movement in a certain period of time, and the calculation formula is: average speed=moving distance/moving time. Wherein, the moving time is the length of the time period, for example, it can be the residence time of the user in the cell included in the cell handover history record, and the moving distance can be estimated as the base station of the cell where the user is at the end time and the cell where the user is at the initial time. The distance between the base stations. In addition, as an example, the selection of the motion time length should enable the user to span multiple base stations within the time period, for example, preferably 1 to 2 minutes. According to the above method, if the average moving speed of the user is greater than a certain threshold, for example, 150-200km/h, it can be determined that the user is a user on a high-speed train.

<<3. Equipment configuration and operation>>

<3.1. Structural configuration and operation of electronic equipment in the target cell>

Fig. 3 is a block diagram schematically showing an example structure of an electronic device of a target cell according to an embodiment of the present disclosure. As shown in FIG. 3, the electronic device 10 includes a processing circuit 100, a memory 101 and a communication unit 102.

According to this embodiment, the processing circuit may be configured to select a representative terminal device among a plurality of terminal devices in the terminal device group, so that the terminal device group can use the representative terminal device as a representative of the terminal device group, with the group as a unit Handover from the original cell to the target cell served by the electronic device.

In the structural example of the electronic device, the processing circuit 100 may be in the form of a general-purpose processor, or may be a special-purpose processing circuit, such as an ASIC. For example, the processing circuit 100 can be constructed by a circuit (hardware) or a central processing device (such as a central processing unit (CPU)). In addition, the processing circuit 100 may carry a program (software) for operating the circuit (hardware) or the central processing device. The program can be stored in the storage 101 (such as arranged in the storage 101) or an external storage medium connected from the outside, and downloaded via a network (such as the Internet).

According to this embodiment, the processing circuit 100 may include a selection unit 1001, and the selection unit 1001 may be configured to select one representative terminal device among a plurality of terminal devices in the terminal device group. According to this embodiment, the selected representative terminal device is reserved for non-contention random access resources.

According to this embodiment, terminal devices can be grouped according to signal spatial characteristics. According to this embodiment, each terminal device in the terminal device group has the same or similar signal spatial characteristics. It is easy to understand that on high-speed vehicles, users holding each terminal device in the same terminal device group are adjacent in space, and maintain a spatially adjacent state during the cell switching time, so they have the same or similar signal space. feature. According to this embodiment, as an example, the signal spatial characteristics include one or more of the following: downlink transmission beam, direct path angle, Doppler shift, path loss, and cell switching history.

According to an embodiment, the terminal device group may be the same as the previous terminal device group when cell handover is performed, or may be changed. As an example, in the case where the terminal device has been grouped in the original cell, another electronic device that the terminal device accesses in the original cell removes the signal spatial characteristics of the original terminal device group that is significantly different from that of other terminal devices in the group. Terminal equipment, and add new terminal equipment similar to the signal space characteristics of the terminal equipment in the group to obtain a new terminal equipment group. As another example, when the terminal device is not grouped in the original cell, another electronic device accessed by the terminal device in the original cell obtains the terminal device group by clustering the signal spatial characteristics.

According to this embodiment, the processing circuit 100 may further include a receiving unit 1002, which may be configured to receive a cell handover request of the terminal device group from another electronic device accessed by the terminal device in the original cell.

In this embodiment, as an example, the selection unit 1001 may select the representative terminal device based on the representative terminal device ID recommended by another electronic device included in the cell handover request of the terminal device group. As another example, the selection unit 1001 may also randomly select the representative terminal device. As another example, the selection unit 1001 may also select the representative terminal device according to its own needs.

In this embodiment, the cell handover request of the terminal device group includes terminal device-specific information, and the terminal device-specific information may include the timing advance (TA) value of each terminal device in the terminal device group in the original cell. The TA value is the time that users need to advance in uplink transmission. Because different users have different distances from the base station, in order to ensure that the uplink signals of different users can reach the base station side at the same time, different users need to be configured with different TA values.

In this embodiment, the processing circuit 100 may further include a sending unit 1003, and the sending unit 1003 may be configured to send the cell handover of the terminal device group to another electronic device serving the original cell in response to the cell handover request of the terminal device group. reply. Among them, as an example, the cell handover response of the terminal equipment group may include terminal equipment-specific information, and the terminal equipment-specific information may include the ID of one or more terminal equipment that is permitted to switch, the ID of the selected representative terminal equipment, and the representative terminal Configuration information of the non-competitive random access resources reserved by the device. It should be noted that the terminal devices that are permitted to switch may be at least some or all of the terminal devices in the terminal device group. In addition, the cell handover response of the terminal equipment group may also include the cell radio network temporary identification (C-RNTI) of each terminal equipment in the terminal equipment group in the target cell.

In this embodiment, in response to the cell handover reply of the terminal device group, another electronic device serving the original cell may send a handover command to the terminal device group. Further, in response to the handover command, all terminal devices in the terminal device group can cut off the connection with the original cell, and perform downlink synchronization on the target cell.

In this embodiment, as an example, the handover command includes a random access indicator indicating whether the terminal device is a representative terminal device. In addition, for the representative terminal device, the handover command may also include the configuration information of the non-competitive random access resource reserved by the electronic device for the representative terminal device.

In this embodiment, the representative terminal device uses the reserved non-competitive random access resource to randomly access the electronic device in the target cell. Specifically, as an example, the representative terminal device can use the reserved non-competitive random access resources to send the preamble sequence to the electronic device, so as to access the electronic device in the target cell. In this embodiment, the time between receiving the handover command and sending the preamble sequence of the representative terminal device is greater than or equal to the predetermined group waiting window time to ensure that the non-representative terminal device can successfully complete the downlink synchronization.

In this embodiment, the processing circuit 100 may further include an information obtaining unit 1004, which is configured to obtain the TA value representing the terminal device in the target cell based on the preamble sequence, for example, when the representative terminal device accesses the target cell Calculation. In addition, the information obtaining unit 1004 may also be configured to obtain the optimal downlink transmission beam representing the terminal device in the target cell based on the preamble sequence.

In addition, in this embodiment, the processing circuit 100 may also include a calculation unit 1005, which is configured to calculate the amount of change in the TA value representing the terminal device in the original cell and the target cell, and by dividing the non-terminal device group The TA value of the representative terminal device in the original cell is added to the change amount of the TA value of the representative terminal device to obtain the TA value of the non-representative terminal device in the target cell.

In this embodiment, the sending unit 1003 is further configured to send a random access response RAR to all terminal devices in the terminal device group. For example, the RAR may be transmitted through a physical downlink shared channel (Physical Downlink Shared Channel, PDSCH) channel, and may include the aforementioned TA value of each terminal device. In this embodiment, the processing circuit 100 may further include a scrambling unit 1006, which is configured to use the C-RNTI of the non-representative terminal device to scramble the RAR to be sent to the non-representative terminal device. In this embodiment, the non-representative terminal device can continuously detect the RAR after completing the downlink synchronization.

In this embodiment, the receiving unit 1002 is further configured to use the uplink transmission resources indicated in the RAR to receive handover completion signaling from the terminal device that successfully detects the RAR, so as to complete a cell handover of the terminal device group.

In addition, in this embodiment, the cell handover request of the terminal device group may be triggered by the measurement report of one or more terminal devices in the terminal device group. As an example, the measurement report may be a measurement report for RSRP. In this embodiment, when the RSRP predicted by the terminal device in the target cell exceeds the RSRP predicted in its original cell by a predetermined threshold, the cell handover request of the terminal device group can be triggered. Among them, for example, the predicted RSRP of the terminal equipment in the original cell and the target cell can be calculated using the currently measured RSRP, the slope of the RSRP change, and the lead time. Among them, as an example, the RSRP change slope can be estimated by fitting the measured RSRP historical value. Among them, the advance time is the difference between the predicted time and the current time. According to this embodiment, the advance time may be configured based on the measured moving speed of the terminal device.

In addition, according to this embodiment, preamble resources corresponding to a part of the downlink transmission beams of the electronic equipment used to transmit the synchronization signal block SSB can be reserved only for the representative terminal equipment, so as to further reduce the cell handover process. Resource overhead.

In addition, optionally, the electronic device 10 may further include the memory 101 and the communication unit 102 shown in dashed lines in FIG. 3. In addition, the electronic device 10 may also include other components not shown, such as a radio frequency link, a baseband processing unit, a network interface, a processor, a controller, and so on. The processing circuit 100 may be associated with the memory 101 and/or the communication unit 102. For example, the processing circuit 100 may be directly or indirectly (for example, other components may be connected in between) connected to the memory 101 to access data. For another example, the processing circuit 100 may be directly or indirectly connected to the communication unit 102 to transmit radio signals via the communication unit 102 and receive radio signals via the communication unit 102.

The memory 101 can store various information generated by the processing circuit 100 and various information to be used by the processing circuit 100 (for example, terminal device specific information, terminal device group common information, etc.), programs and data used for the operation of the electronic device 10, Data etc. to be transmitted by the communication unit 102. The memory 101 is drawn with a dashed line because it can also be located inside the processing circuit 100 or outside the electronic device 10. The memory 101 may be a volatile memory and/or a non-volatile memory. For example, the memory 101 may include, but is not limited to, random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), read only memory (ROM), and flash memory.

The communication unit 102 may be configured to communicate with other electronic devices and terminal devices under the control of the processing circuit 100. In an example, the communication unit 102 may be implemented as a transmitter or transceiver, including communication components such as an antenna array and/or a radio frequency link. In an embodiment, the communication unit 102 may send the cell handover reply of the terminal device group determined in the processing circuit 100 to another electronic device serving the original cell. In an embodiment, the communication unit 102 may also send and receive signaling required for the procedures described in the embodiments of the present disclosure.

Although FIG. 3 shows that the processing circuit 100 is separated from the communication unit 102, the processing circuit 100 may also be implemented to include the communication unit 102. In addition, the processing circuit 100 may also be implemented to include one or more other components in the electronic device 10, or the processing circuit 100 may be implemented as the electronic device 10 itself. In actual implementation, the processing circuit 100 may be implemented as a chip (such as an integrated circuit module including a single wafer), a hardware component, or a complete product.

It should be noted that the above-mentioned units are only logical modules divided according to the specific functions they implement, and are not used to limit specific implementation manners. For example, they may be implemented in software, hardware, or a combination of software and hardware. In actual implementation, each of the above-mentioned units may be implemented as an independent physical entity, or may also be implemented by a single entity (for example, a processor (CPU or DSP, etc.), an integrated circuit, etc.). In addition, the above-mentioned various units are shown with dotted lines in the drawings to indicate that these units may not actually exist, and the operations/functions they implement can be implemented by the processing circuit itself.

Hereinafter, the grouped cell handover scheme and the prediction-based cell handover scheme implemented by the electronic device will be exemplarily explained with reference to FIGS. 4-9.

Fig. 4 schematically shows a flowchart of the operation of the electronic device of the target cell according to an embodiment of the present disclosure.

First, in step S401, the electronic device receives a cell handover request of the terminal device group from another electronic device accessed by the terminal device in the original cell.

According to this embodiment, each terminal device in the terminal device group has the same or similar signal spatial characteristics. Ideally, terminal devices in close proximity (for example, terminal devices located in the same compartment) should be grouped into the same group. However, in an actual communication system, it is often difficult for a base station to accurately determine the location of a terminal device. Therefore, in some embodiments, signal spatial characteristics may be used to group terminal devices. According to this embodiment, when the terminal device is not grouped in the original cell, another electronic device accessed by the terminal device in the original cell can obtain the terminal device group by clustering the signal spatial characteristics.

Specifically, the terminal devices in the same group have the same beam, similar cell switching history, similar path loss, similar direct radius angle, and similar Doppler shift due to their similar locations. Therefore, these features can be formed into high-dimensional feature vectors, and the high-dimensional feature vectors of multiple terminal devices can be clustered (for example, using the K-means algorithm, etc.) to obtain multiple terminal device groups.

According to the embodiment, since the TA value of the user is related to the beam, it is a necessary condition that users in the same user group have the same base station downlink transmission beam. In addition, there are generally two types of downlink transmission beams of the base station, the beam used to transmit the synchronization signal block SSB and the beam used to transmit the physical downlink shared channel PDSCH. Since the cell handover process mainly involves the beam corresponding to the SSB, the beam corresponding to the SSB is selected for user grouping.

As an example, FIG. 5 schematically shows a flowchart of signaling for grouping terminal devices according to an embodiment of the present disclosure. As shown in FIG. 5, in step S501, the terminal device sends an uplink reference signal to the electronic device serving it. Next, in step S502, the electronic device can estimate the signal spatial characteristics of the terminal device based on the received uplink reference signal, including but not limited to downlink transmission beam, direct beam angle, Doppler frequency shift, path loss, etc. . Next, in step S503, the electronic device sends a signaling for querying the cell handover history of the terminal device to the MME. Then, after receiving the cell switching history query signaling, the MME returns its previously stored cell switching history of the terminal device to the electronic device, as shown in step S504. Finally, in step S505, the electronic device groups the terminal devices according to the cell handover history received from the MME and its estimated signal space characteristics.

In some embodiments, other information such as the in-car Wifi system and the device room (D2D) system can also be used to assist terminal device grouping. For example, it is possible to assist terminal device grouping based on characteristics of similar signal strengths of Wifi access points measured by terminal devices in similar locations.

According to this embodiment, the terminal device grouping during cell handover may be the same as the previous terminal device grouping, or may be changed, for example, dynamically adjusted according to signal spatial characteristics. As an example, in the case where the terminal device has been grouped in the original cell, another electronic device that the terminal device can access in the original cell removes the signal space characteristics of the original terminal device group that are significantly different from other terminal devices in the group. Terminal equipment, and add new terminal equipment similar to the signal space characteristics of the terminal equipment in the group to obtain a new terminal equipment group.

It should be understood that the grouping of terminal devices is not limited to the above description. It can be performed by the electronic devices serving the terminal devices in the original cell, or by the electronic devices to be served by the terminal devices in the target cell, or by the network side. MME proceeded.

According to this embodiment, the cell handover request of the terminal device group may include terminal device group common information and terminal device specific information. Among them, the terminal device group shared information is the same information for the terminal devices in the same terminal device group. As shown in FIG. 6, the cell handover request of the terminal device group includes information common to the terminal device group and information unique to the terminal devices 1 to K. All terminal devices in the terminal device group can reduce the Xn/X2 interface signaling overhead by multiplexing the common information of the terminal device group.

According to this embodiment, the terminal device-specific information in the cell handover request of the terminal device group may include the TA value of each terminal device in the terminal device group in the original cell. In some embodiments, the terminal device group shared information in the cell handover request of the terminal device group may include the target cell ID and the minimum system information of the original cell.

Referring back to FIG. 4, next, in step S402, the electronic device determines whether the terminal device group is permitted to perform cell handover. In the case that the cell handover request is permitted ("Yes" in step S402), in step S403, the electronic device selects one representative terminal device among the multiple terminal devices in the terminal device group, and then, in step S404, the original Another electronic device in the cell sends a cell handover reply of the terminal device group.

According to this embodiment, the cell handover response of the terminal device group may include terminal device group common information and terminal device specific information. Wherein, the terminal device group shared information is the same information for the terminal devices in the same terminal device group. As shown in FIG. 6, the cell handover response of the terminal device group includes information shared by the terminal device group and information unique to the terminal devices 1 to K. All terminal devices in the terminal device group can reduce the Xn/X2 interface signaling overhead by multiplexing the common information of the terminal device group.

According to this embodiment, the terminal device-specific information in the cell handover response of the terminal device group may include the ID of one or more terminal devices that are permitted to switch, the ID of the selected representative terminal device, and the non-specific information reserved for the representative terminal device. Configuration information for competing random access resources. In some embodiments, the terminal device group shared information in the cell handover response of the terminal device group may include the target cell ID, the target cell security algorithm identifier, and the target cell system information block.

According to this embodiment, the representative terminal device can be selected by the target cell in various ways. In some embodiments, the electronic device may also randomly select the representative terminal device or select the representative terminal device according to its own needs. As an example, it can be selected randomly from the terminal device group, or can be selected based on some terminal device characteristics (such as RSRP, etc.).

In some embodiments, in order to support subsequent grouped random access, the cell handover request of the terminal device group may also include a representative terminal device ID recommended by another electronic device serving the original cell. According to this embodiment, the electronic device can select the representative terminal device based on the representative terminal device ID recommended by another electronic device in the original cell. As an example, generally, the electronic device in the target cell does not know the characteristics of the terminal device. Therefore, another electronic device providing service in the original cell can recommend a suitable representative terminal device according to the characteristics of the terminal device. For example, the terminal device with the best channel quality (for example, the largest RSRP) can be recommended as the representative terminal device, and the The ID representing the terminal device is included in the cell handover request of the terminal device group and sent to the electronic device providing the service in the target cell.

In order to support subsequent grouped random access, according to this embodiment, the cell handover response of the terminal device group may also include the C-RNTI of each terminal device in the terminal device group in the target cell.

According to this embodiment, in response to the cell handover reply of the terminal device group, another electronic device in the original cell sends a handover command to the terminal device group. According to this embodiment, the handover command may include a random access indicator indicating whether the terminal device is a representative terminal device. As an example, for a representative terminal device, the random access indicator may be 1, and for a non-representative terminal device, the random access indicator may be 0. According to this embodiment, for the representative terminal device, the handover command may also include the configuration information of the non-competitive random access resources reserved for the representative terminal device by the electronic device in the target cell, so as to inform the representative terminal device of the non-competitive random access resources reserved for the representative terminal device. Competing for random access resources.

Referring back to FIG. 4, next, in step S405, the electronic device receives the random access of the terminal device group. Specifically, it represents that the terminal device cuts off the connection with the original cell and synchronizes downlink with the electronic device in the target cell. Then, the representative terminal device uses the non-competitive random access resources reserved for it to randomly access the electronic device in the target cell. As an example, the representative terminal device uses the reserved non-competitive random access resources to send the preamble sequence to the electronic device. The electronic device in the target cell detects the optimal uplink receiving beam based on the preamble sequence, and uses the downlink transmission beam and the uplink random access The corresponding relationship of resources obtains the optimal downlink transmission beam.

It is easy to understand that since the downlink transmission beams of each terminal device in the same user terminal equipment group are the same, the optimal downlink transmission beam of the representative terminal device is also the optimal downlink transmission beam of other non-representative terminal devices in the group, so that the non-representative terminal The device also cuts off the connection with the original cell, and synchronizes downlink with the electronic device in the target cell, and then can use the optimal downlink transmission beam to randomly access the electronic device in the target cell.

According to this embodiment, the time between receiving the switching command and sending the preamble sequence of the representative terminal device is greater than or equal to the predetermined group waiting window time, as shown in FIG. 6, thereby ensuring that the non-representing terminal device can wait in the group waiting window time The downlink synchronization is completed internally to avoid failure of non-representative terminal equipment access, thereby improving the robustness of the communication system.

Next, in step S406, the electronic device sends a random access response RAR to the terminal device. In some embodiments, the electronic device sends a random access response RAR to all terminal devices in the terminal device group. In this embodiment, RAR may include TA value, C-RNTI and uplink transmission resources. In some embodiments, the electronic device may send RAR in the public physical downlink control channel (PDCCH) space.

According to an embodiment, the TA value contained in the RAR may include a TA value that is not representative of the terminal device, and the TA value may be calculated as follows. According to this embodiment, the electronic device can also obtain the TA value representing the terminal device in the target cell based on the preamble sequence. Since the cell handover time is relatively short (usually within tens of ms to hundreds of ms), it can be assumed that the user terminal clock is stable during the cell handover process. Therefore, for all terminal equipment in the same terminal equipment group, the TA during the cell handover process The change (that is, the difference between the TA value in the target cell and the TA value in the original cell) is basically the same. According to this embodiment, the electronic device can calculate the amount of change in the TA value of the representative terminal device in the original cell and the target cell, and by comparing the TA value of the non-representative terminal device in the original cell of the terminal device group with the TA value of the representative terminal device Add the changes of, to obtain the TA value of the non-representative terminal equipment in the target cell. The calculation formula for the new TA value of the non-representative terminal device in the target cell may be: the target cell of the non-representative terminal device TA=the original cell TA of the non-representative terminal device+the TA change amount of the representative terminal device.

In order to enable the non-representative terminal device to receive and correctly decode the RAR sent by the electronic device in the target cell, in this embodiment, the electronic device uses the C-RNTI of the non-representative terminal device to perform the RAR to be sent to the non-representative terminal device. Scrambled. Since the C-RNTI of the terminal equipment in the target cell has been included in the cell handover response and sent to the terminal equipment through the handover command, the terminal equipment has obtained the C-RNTI in the new cell before accessing the target cell , And then the received RAR can be decoded through C-RNTI.

In addition, since the TA value of the non-representative terminal device can be calculated after the representative terminal device completes random access, the RAR of the non-representative terminal device needs to be transmitted after the representative terminal device completes the random access, so the non-representative terminal device does not know the RAR When will it be transmitted, in this embodiment, the non-representative terminal device needs to continuously detect the RAR after completing the downlink synchronization, as shown in FIG. 6. In some embodiments, non-representative terminal devices can continuously detect RAR in the common PDCCH space.

Although here is divided into two steps S405 and S406 to describe receiving random access and sending random access response, in some embodiments, steps S405 and S406 may also be collectively referred to as a random access process.

Finally, in step S407, the electronic device can use the uplink transmission resource indicated in the RAR to receive the handover completion signaling from the terminal device that successfully detects the RAR, and then complete the cell handover.

In addition, according to this embodiment, the cell handover request of the terminal device group may be triggered by a measurement report of one or more terminal devices in the terminal device group, for example, it may be triggered by an RSRP measurement report.

A variety of measurement events are defined in the existing NR/LTE system. When the measurement event conditions are met, a measurement report is triggered, and the electronic equipment in the original cell decides whether to perform cell handover according to the measurement report. As an example, the measurement event A3 defined in the NR/LTE system means that the RSRP of the neighboring cell is higher than the RSRP of the current cell and exceeds a certain threshold (for example, it can be 3dB or 6dB).

However, it should be noted that the measurement report is usually performed after a period of time (for example, 200 ms) has passed after the measurement event is triggered. In addition, the radio protocol stack usually has three layers: layer 1, layer 2, and layer 3. Among them, layer 1 (L1) is the lowest layer and implements various physical layer signal processing to provide transparent transmission of signals; layer 2 (L2 layer) is above the physical layer and is responsible for the communication between the terminal device and the electronic device. The upper link; Layer 3 (L3 layer) is responsible for obtaining radio resources (ie, radio bearers) and for configuring the lower layers using RRC signaling between the electronic device and the terminal device. Users usually use L3 RSRP to trigger measurement events. L3 RSRP is obtained after filtering by L1 RSRP. Although it is more accurate, there is a certain delay.

FIG. 8A schematically shows the change over time of the reference signal received power RSRP of the original cell and the target cell of the terminal device. During the movement of the high-speed train, the terminal equipment on the train is getting farther and farther from the original cell, and the distance from the target cell is getting closer. Therefore, as shown in Figure 8A, the L3 RSRP of the original cell (as shown by the dashed line) The indicated) keeps decreasing with time, and the L3 RSRP (as indicated by the solid line) of the target cell keeps increasing with time.

In the traditional solution, when the target cell L3 RSRP of the terminal device exceeds the original cell L3 RSRP threshold τ, the measurement event can be triggered. After the trigger time TTT and the handover preparation time between the original cell and the target cell, the original cell sends the message to the terminal device. Switch command. Since the terminal equipment on the high-speed train moves faster, the original cell L3 RSRP of the terminal equipment at this time may have been reduced to the extent that it cannot receive the handover command correctly, which will cause the cell handover to fail.

To solve this problem, the present disclosure proposes a cell handover scheme based on prediction. In this embodiment, when the RSRP predicted by the terminal device in the target cell exceeds the RSRP predicted in its original cell by a predetermined threshold, a cell handover request of the terminal device group can be triggered.

As shown in FIG. 8B, the predicted L3 RSRP of the terminal equipment in the original cell and the target cell can be calculated by using the currently measured RSRP, the slope of RSRP change and the advance time. Specifically, the prediction formula of L3 RSRP is as follows:

Forecast L3 RSRP = current L3 RSRP + L3 RSRP change slope × advance time

Among them, the slope of the L3 RSRP change can be estimated by fitting the measured RSRP historical value, for example, it can be obtained by fitting and estimating the L3 RSRP value in the most recent period of time using an algorithm such as the least square method. The advance time is the time difference between the predicted time and the current time, which can be configured in advance based on the measured moving speed of the terminal device. For example, the faster the moving speed, the more advance time can be configured. For terminal equipment on high-speed vehicles, because the moving track is fixed, the optimal lead time can be obtained through long-term learning, and the lead time that makes the handover success rate the highest can be selected by the terminal equipment of the original cell. In addition, for the RSRP in the original cell and the target cell, the prediction is made independently.

As described above, a measurement event based on prediction can be defined, for example, the L3 RSRP predicted by the target cell exceeds a certain threshold τ predicted by the original cell. Using this prediction-based measurement event can trigger cell handover in advance to ensure that when the original cell sends a handover command to the terminal device, the original cell RSRP of the terminal device is still large enough to reduce the probability of handover failure.

Although the above description is only for L3 RSRP, it should be understood that the above prediction-based cell handover scheme is also applicable to the case of using L1 RSRP or other parameters. In addition, please note that this prediction-based principle is also applicable to improve other measurement events defined in the NR/LTE system.

FIG. 9 is an exemplary signaling flowchart schematically showing a packet-based cell handover scheme according to an embodiment of the present disclosure.

As shown in FIG. 9, in step S901, the electronic device 30 serving the user in the original cell performs measurement control on the terminal device 20 of the user. Then, in step S902, the terminal device 20 performs measurement based on the control of the electronic device 30, and reports the measurement result to the electronic device 30. Among them, the measurement may include the measurement of the RSRP of the terminal device 20, and may also include the measurement of other parameters.

Next, in step S903, the electronic device 30 determines whether to perform the cell handover of the terminal device group based on the defined cell handover condition based on prediction. For example, when the measurement report of one or more terminal devices in the terminal device group meets the cell handover condition, it may be determined to perform the cell handover of the terminal device group.

When the electronic device 30 makes a cell switching decision of the terminal device group, in step S904, the electronic device 30 sends a cell switching request of the terminal device group to the electronic device 10 that will serve the terminal device 20 in the target cell to be switched to , To initialize the cell handover of the terminal equipment group. Wherein, the cell handover request of the terminal device group may include terminal device group common information and terminal device specific information, and the terminal device specific information may include the TA value of each terminal device in the original cell.

Next, in step S905, the electronic device 10 of the target cell performs admission control to allow or reject the cell handover request of the terminal device group. When the cell handover request of the terminal device group is permitted, the electronic device 10 selects a terminal device from the terminal device group as the representative terminal device, and reserves non-competitive random access resources for it.

Next, in step S906, the electronic device 10 in the target cell sends a cell handover response of the terminal device group to the electronic device 30 in the original cell. Among them, the cell handover response of the terminal equipment group may include terminal equipment group common information and terminal equipment specific information, and the terminal equipment specific information may include the ID of one or more terminal equipment that permits the cell handover, the ID of the selected representative terminal equipment, and Configuration information of the non-competitive random access resource reserved for the representative terminal device.

Next, in step S907, the electronic device 30 of the original cell generates a handover command for each terminal device, and in step S908, sends the handover command to the terminal device that is permitted to switch the cell. Wherein, the handover command may include a random access indicator, for example, for a representative terminal device, the random access indicator is 1, and for a non-representative terminal device, the random access indicator is 0. In addition, for the representative terminal device, the handover command may also include the configuration information of the non-contention random access resource reserved for the target cell.

Next, in step S909, the terminal device that has received the handover command cuts off the connection with the original cell, and performs downlink synchronization on the target cell. Subsequently, in step S910, the representative terminal device uses the reserved non-competitive random access resources to perform random access to the target cell. The electronic device 10 in the target cell obtains the optimal downlink transmission beam and TA value representing the terminal device, and further calculates the TA value of the non-representative terminal device in the terminal device group.

Next, in step S911, the electronic device 10 of the target cell sends an RAR to all terminal devices in the terminal device group. Among them, for the representative terminal device, the method in the existing standard can be used to send the RAR, and for the non-representative terminal device, the RAR can be sent after being scrambled by the C-RNTI. Among them, the non-representative terminal device continues to detect RAR after downlink synchronization.

Finally, in step S912, the terminal device that successfully detects the RAR uses the uplink transmission resource indicated in the RAR to send the handover completion signaling to the electronic device 10 in the target cell, and the cell handover is completed since then.

It should be understood that only the main signaling flow in the specific example of the grouped cell handover according to the embodiment of the present disclosure is shown here, and the grouped cell handover according to the present disclosure naturally also includes other auxiliary information required to complete the cell handover. make. According to the principle of cell handover and the signaling process as described above, the grouped cell handover according to the embodiment of the present disclosure is completed.

The packet-based cell handover and prediction-based cell handover technologies according to exemplary embodiments of the present disclosure have been explained above with reference to FIGS. 4-9. According to the group-based cell handover as described above, it is possible to perform cell handover for users on high-speed vehicles at the same time as a group, which speeds up the handover. Only one representative user in each group is selected for random access, which is significant The resource overhead is reduced, and the probability of random access conflicts when a large number of users perform cell handover at the same time is reduced, thereby reducing the handover delay. In addition, according to the prediction-based cell handover as described above, the cell handover can also be triggered in advance based on prediction, thereby effectively reducing the probability of handover failure. Please note that the aforementioned packet-based cell handover and prediction-based cell handover techniques can be used separately or in combination.

In addition, in the wireless communication process, the initial access process of the user's terminal equipment requires the base station (ie, electronic device) to obtain the optimal downlink transmission beam for each user, which is achieved through the downlink synchronization signal block SSB and the uplink preamble sequence. The fixed mapping relationship is determined, where each SSB corresponds to a downlink transmit beam. Specifically, the base station periodically sends the downlink synchronization signal block SSB, the user detects the SSB with the largest RSRP, and determines the preamble sequence used in the uplink random access process through the correspondence between the downlink SSB and the uplink preamble sequence. Subsequently, the user sends the preamble sequence for random access, and the base station can obtain the SSB with the largest RSRP by detecting the preamble sequence used by the user, thereby determining the optimal downlink transmission beam.

In a non-competitive random access scenario, preamble sequence resources are reserved for users. It can be seen that the more SSBs, the more preamble sequence resources that need to be reserved, resulting in greater resource overhead. In order to further reduce the resource overhead in the cell handover process, the present invention proposes that only the preamble sequence corresponding to a part of the SSB can be reserved. In this embodiment, the preamble sequence resources corresponding to a part of the downlink transmission beams of the base station for transmitting the downlink SSB may be reserved only for the representative terminal equipment.

This is because for users on high-speed trains, because their moving trajectories are fixed, inter-cell handover usually occurs in a relatively fixed area, such as the handover area shown in FIG. 10. The downlink transmission beam of the base station corresponding to the handover area is a subset of all possible downlink transmission beams, as shown by the downlink transmission beams marked in black in FIG. 10. This subset of downlink transmission beams is commonly used in the cell handover process, so the base station can only configure the preamble sequence resources corresponding to this subset of downlink transmission beams. In some embodiments, the downlink transmission beam subset of the base station corresponding to the handover area may be obtained by long-term learning of the optimal downlink transmission beam when users on high-speed trains access the cell.

In addition, although the above description only separately describes the electronic device 10 of the target cell and the electronic device 30 of the original cell, it should be understood that the electronic device 10 of the target cell and the electronic device 30 of the original cell can also be used interchangeably, and are aimed at The functions described by the two can be integrated in the same electronic device.

<3.2. Configuration and operation of terminal equipment>

Hereinafter, the terminal device of the present disclosure will be described with reference to the accompanying drawings. It should be noted that some terms described herein may have similar meanings as described above. FIG. 11 is a block diagram schematically showing an example structure of a terminal device according to an embodiment of the present disclosure. As shown in FIG. 11, the terminal device 20 includes a processing circuit 200, a memory 201, and a communication unit 202.

According to this embodiment, the processing circuit 200 may be configured to trigger the electronic device on the control side of the wireless communication system serving the terminal device to send a cell handover request for the terminal device group including the terminal device and receive the cell handover of the corresponding terminal device group. In reply, the terminal device group uses one of the terminal devices as the representative terminal device to switch from the original cell served by the electronic device to the target cell in a group unit. Further, the processing circuit 200 may be configured to trigger the electronic device to send a cell switching request of the terminal device group when the terminal device moves along a specific track and the moving speed is greater than a specific threshold, and the measurement report meets the cell switching condition.

In the structural example of the terminal device 20, the processing circuit 200 may be in the form of a general-purpose processor, or may be a dedicated processing circuit, such as an ASIC. For example, the processing circuit 200 can be constructed by a circuit (hardware) or a central processing device (such as a central processing unit (CPU)). In addition, the processing circuit 200 may carry a program (software) for operating the circuit (hardware) or the central processing device. The program can be stored in the storage 201 (such as arranged in the storage) or an external storage medium connected from the outside, and downloaded via a network (such as the Internet).

According to this embodiment, the processing circuit 200 may include a receiving unit 2001, which may be configured to receive a measurement control command from an electronic device in the original cell. In addition, according to this embodiment, the receiving unit 2001 may also be configured to receive a handover command from the electronic device of the original cell. In addition, according to this embodiment, the receiving unit 2001 may also be configured to receive the random access response RAR from the electronic device of the target cell.

According to this embodiment, the processing circuit 200 may further include a measurement unit 2002, which may be configured to measure the terminal device in response to a measurement control command, for example, may measure L1 RSRP or L3 RSRP.

According to this embodiment, the processing circuit 200 may further include a sending unit 2003, which is configured to send a measurement report to the electronic device of the original cell to report the measurement result thereto. In addition, according to this embodiment, the sending unit 2003 may also be configured to use the reserved non-competitive random access resources to send the preamble sequence to the electronic device of the target cell when the terminal device is the representative terminal device, so as to access the target cell. Electronic equipment. In addition, in some embodiments, the sending unit 2003 may also be configured to, when the terminal device successfully detects the RAR, use the uplink transmission resources indicated in the RAR to send the handover complete to the electronic device to be accessed by the terminal device in the target cell. Signaling.

In some embodiments, terminal devices can be grouped by electronic devices according to their signal spatial characteristics and cell switching history. In some embodiments, the signal spatial characteristics can be estimated by the electronic device based on the uplink reference signal sent by the terminal device, and the cell handover history can be obtained by the electronic device from the mobility management unit. Further, in some embodiments, terminal devices with the same or similar signal spatial characteristics may be grouped into a group. In some embodiments, the terminal device group may include one representative terminal device and one or more non-representative terminal devices.

In addition, the processing circuit 200 may further include a synchronization unit 2004, which may be configured to cut off the connection with the original cell in response to the handover command, and perform downlink synchronization on the target cell.

In addition, according to this embodiment, the processing circuit 200 may include a detection unit 2005, which may be configured to detect a random access response RAR. According to this embodiment, when the terminal device is a non-representative terminal device, after the downlink synchronization is completed, the detection unit 2005 continuously detects the random access response RAR.

In addition, optionally, the terminal device 20 may further include a memory 201 and a communication unit 202 shown in dashed lines in the figure. In addition, the terminal device 20 may also include other components not shown, such as a radio frequency link, a baseband processing unit, a network interface, a processor, a controller, and so on. The processing circuit 200 may be associated with the memory 201 and/or the communication unit 202. For example, the processing circuit 200 may be directly or indirectly connected to the memory 201 (for example, other components may be connected in between) to access data. For another example, the processing circuit 200 may be directly or indirectly connected to the communication unit 202 to transmit radio signals via the communication unit 202 and receive radio signals via the communication unit 202.

The memory 201 may store various information (for example, measurement results, handover completion signaling, etc.) generated by the processing circuit 200, programs and data for operation of the terminal device 20, data to be transmitted by the communication unit 202, and the like. The memory 201 is drawn with a dashed line because it can also be located in the processing circuit 200 or located outside the terminal device 20. The memory 201 may be a volatile memory and/or a non-volatile memory. For example, the memory 201 may include, but is not limited to, random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), read only memory (ROM), flash memory.

The communication unit 202 may be configured to communicate with an electronic device under the control of the processing circuit 200. In an example, the communication unit 202 may be implemented as a transmitter or transceiver, including communication components such as an antenna array and/or a radio frequency link. In an embodiment, the communication unit 202 may send the measurement result of at least one terminal device obtained by the processing circuit 200 to the electronic device. In an embodiment, the communication unit 202 may also send and receive signaling required for the procedures described in the embodiments of the present disclosure.

Although it is shown in FIG. 11 that the processing circuit 200 is separated from the communication unit 202, the processing circuit 200 may also be implemented to include the communication unit 202. In addition, the processing circuit 200 may also be implemented to include one or more other components in the terminal device 20, or the processing circuit 200 may be implemented as the terminal device 20 itself. In actual implementation, the processing circuit 200 may be implemented as a chip (such as an integrated circuit module including a single wafer), a hardware component, or a complete product.

FIG. 12 is a flowchart schematically showing the operation of the terminal device according to an embodiment of the present disclosure.

As shown in Fig. 12, in step S1201, the terminal device receives a measurement control command from the electronic device of the original cell. Next, in step S1202, the terminal device performs measurement in response to the measurement control command, and sends a measurement report to the electronic device.

In some embodiments, when the terminal device moves along a specific trajectory and the moving speed is greater than a specific threshold, and the measurement report meets the cell handover condition, the electronic device is triggered to send the cell handover request of the terminal device group and receive the cell handover of the corresponding terminal device group In reply, the terminal device group uses one of the terminal devices as the representative terminal device to switch from the original cell served by the electronic device to the target cell in a group unit.

In some embodiments, terminal devices are grouped by electronic devices according to their signal spatial characteristics and cell switching history. In some embodiments, the signal spatial characteristics are estimated by the electronic device based on the uplink reference signal sent by the terminal device. In some embodiments, the cell handover history is obtained by the electronic device inquiring from the mobility management unit. In some embodiments, terminal devices with the same or similar signal spatial characteristics are grouped together. In some embodiments, the terminal device group includes one representative terminal device and one or more non-representative terminal devices.

Next, in step S1203, the terminal device receives a switching command from the electronic device. Then, in step S1204, in response to the handover command, the terminal device cuts off the connection with the original cell, and performs downlink synchronization on the target cell.

Next, in step S1205, the terminal device group randomly accesses the target cell. In some embodiments, when the terminal device is a representative terminal device, it uses the reserved non-competitive random access resources to randomly access the electronic device in the target cell, and receives a random access response RAR from the electronic device in the target cell . In some embodiments, when the terminal device is the representative terminal device, it uses the reserved non-competitive random access resources to send the preamble sequence to the electronic device in the target cell, thereby accessing the electronic device in the target cell, and the non-representative terminal The device can also access the electronic device in the target cell by using the optimal downlink transmission beam determined based on the preamble sequence. In some embodiments, when the terminal device is a non-representative terminal device, it continuously detects the random access response RAR after completing the downlink synchronization.

Finally, in step S1206, when the terminal device successfully detects the RAR, the uplink transmission resource indicated in the RAR is used to send the handover completion signaling to the electronic device to be accessed by the terminal device in the target cell.

<3.3. Structural configuration and operation of electronic equipment in the original cell>

The electronic equipment of the original cell of the present disclosure will be described below with reference to the accompanying drawings. It should be noted that some terms described herein may have similar meanings as described above. FIG. 13 is a block diagram schematically showing an example structure of another electronic device according to an embodiment of the present disclosure. As shown in FIG. 13, the electronic device 30 includes a processing circuit 300, a memory 301, and a communication unit 302.

According to this embodiment, the processing circuit 300 may be configured to send a cell handover request of the terminal device group to the electronic device in the target cell and receive the cell handover response of the terminal device group from the electronic device in the target cell, so that the terminal device group is As a representative terminal device, one terminal device of the group is handed over from the original cell to the target cell in a group.

In the above structural example of the electronic device 30, the processing circuit 300 may be in the form of a general-purpose processor, or may be a special-purpose processing circuit, such as an ASIC. For example, the processing circuit 300 can be constructed by a circuit (hardware) or a central processing device (such as a central processing unit (CPU)). In addition, the processing circuit 300 may carry a program (software) for operating the circuit (hardware) or the central processing device. The program can be stored in the storage 301 (such as arranged in a storage) or an external storage medium connected from the outside, and downloaded via a network (such as the Internet).

According to this embodiment, the processing circuit 300 may include a sending unit 3001, which may be configured to send a cell handover request of the terminal device group to the electronic device in the target cell. According to this embodiment, the sending unit 3001 may also be configured to send a cell handover request of the terminal device group to the electronic device serving the target cell when the measurement report of the terminal device meets the cell handover condition. In some embodiments, the cell handover request of the terminal device group may include the representative terminal device ID recommended by the electronic device 30 to the electronic device of the target cell. According to this embodiment, the sending unit 3001 may also be configured to send a cell handover history query command to the mobility management unit.

According to this embodiment, the processing circuit 300 may further include a receiving unit 3002, which may be configured to receive the cell handover reply of the terminal device group from the electronic device of the target cell. In some embodiments, the receiving unit 3002 may also be configured to receive measurement reports from one or more terminal devices in the terminal device group. In some embodiments, the receiving unit 3002 may also be configured to receive the cell handover history of the terminal device from the mobility management unit. In some embodiments, the receiving unit 3002 may also be configured to receive an uplink reference signal from a terminal device.

According to this embodiment, the processing circuit 300 may further include a grouping unit 3003, which may be configured to group the terminal devices served by the electronic device 30 into one or more terminal device groups, wherein each terminal device group includes a representative terminal. Device and one or more non-representative terminal devices. In some embodiments, the grouping unit 3003 may also be configured to group the terminal devices according to the signal space characteristics of the terminal devices and the cell switching history. In some embodiments, the grouping unit 3003 may also be configured to group terminal devices with the same or similar signal spatial characteristics by clustering the signal spatial characteristics when the terminal devices are not originally grouped; and When the terminal devices have been grouped in the original group, by removing the terminal devices in the original terminal device group that are significantly different from the other terminal devices in the group, and adding new terminal devices that are similar to the signal space characteristics of the terminal devices in the group , Get a new terminal equipment group.

According to this embodiment, the processing circuit 300 may further include an estimation unit 3004, which may be configured to estimate the signal spatial characteristics of the terminal device based on the uplink reference signal received by the receiving unit 3002.

According to this embodiment, the processing circuit 300 may further include a selection unit 3005, which may be configured to select a representative terminal device according to the characteristics of the terminal device.

According to this embodiment, the sending unit 3001 may also be configured to send a handover command to the terminal device group in response to the cell handover reply of the terminal device group. In some embodiments, the handover command includes the cell radio network temporary identification C-RNTI of each terminal device in the terminal device group in the target cell. In some embodiments, the sending unit 3001 may be further configured to send the terminal device to the electronic device serving the target cell when the RSRP predicted by the terminal device in the target cell exceeds the RSRP predicted in the original cell by a predetermined threshold. The cell handover request of the device group.

According to this embodiment, the processing circuit 300 may also have a calculation unit 3006, which may be configured to use the currently measured RSRP, RSRP change slope and lead time to calculate the predicted RSRP of the terminal device in the original cell and the target cell. In some embodiments, the estimation unit 3004 may also be configured to use the measured historical RSRP value to fit the estimated RSRP change slope. In some embodiments, the lead time may be configured based on the measured moving speed of the terminal device.

In addition, optionally, the electronic device 30 may further include a memory 301 and a communication unit 302 shown in dashed lines in the figure. In addition, the electronic device 30 may also include other components not shown, such as a radio frequency link, a baseband processing unit, a network interface, a processor, a controller, and so on. The processing circuit 300 may be associated with the memory 301 and/or the communication unit 302. For example, the processing circuit 300 may be directly or indirectly (for example, other components may be connected in between) connected to the memory 301 to access data. For another example, the processing circuit 300 may be directly or indirectly connected to the communication unit 302 to transmit radio signals via the communication unit 302 and receive radio signals via the communication unit 302.

The memory 301 can store various information generated by the processing circuit 300 (for example, terminal device grouping information, signal spatial characteristics, selected representative terminal device IDs, etc.), programs and data used for the operation of the electronic device 30, and will be used by the communication unit 302 Data sent, etc. The memory 301 is drawn with a dashed line because it can also be located inside the processing circuit 300 or outside the electronic device 30. The memory 301 may be a volatile memory and/or a non-volatile memory. For example, the memory 301 may include, but is not limited to, random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), read only memory (ROM), and flash memory.

The communication unit 302 may be configured to communicate with electronic devices and terminal devices under the control of the processing circuit 300. In an example, the communication unit 302 may be implemented as a transmitter or transceiver, including communication components such as an antenna array and/or a radio frequency link. In an embodiment, the communication unit 302 may send the representative terminal device ID determined in the processing circuit 300 to the electronic device of the original cell in the wireless communication system. In an embodiment, the communication unit 302 may also send and receive signaling required for the procedures described in the embodiments of the present disclosure.

Although it is shown in FIG. 13 that the processing circuit 300 is separated from the communication unit 302, the processing circuit 300 may also be implemented to include the communication unit 302. In addition, the processing circuit 300 may also be implemented to include one or more other components in the electronic device 30, or the processing circuit 300 may be implemented as the electronic device 30 itself. In actual implementation, the processing circuit 300 may be implemented as a chip (such as an integrated circuit module including a single wafer), a hardware component, or a complete product.

FIG. 14 is a flowchart schematically showing the operation of the electronic device of the original cell according to an embodiment of the present disclosure.

As shown in FIG. 14, in step S1401, the electronic device groups the terminal devices. Specifically, the electronic device groups the terminal devices it serves into one or more terminal device groups, where each terminal device group includes a representative terminal device and one or more non-representative terminal devices.

In some embodiments, the electronic device may group the terminal devices according to the signal space characteristics of the terminal device and the cell switching history. In some embodiments, the electronic device sends a cell handover history query command to the mobility management unit, and then receives the cell handover history of the terminal device from the mobility management unit. In some embodiments, the electronic device receives the uplink reference signal from the terminal device, and then estimates the signal spatial characteristics of the terminal device based on the received uplink reference signal.

In some embodiments, when the terminal devices are not originally grouped, the electronic device clusters the signal spatial characteristics to group terminal devices with the same or similar signal spatial characteristics. In other embodiments, when the terminal devices have been grouped originally, the electronic device removes the terminal devices in the original terminal device group that have a large difference in signal space characteristics from other terminal devices in the group, and adds the difference between the terminal devices in the group and the terminal devices in the group. New terminal equipment with similar signal spatial characteristics will get a new terminal equipment group.

Next, in step S1402, the electronic device selects a representative terminal device according to the characteristics of the terminal device. Note that step S1402 is not necessary, and the representative terminal device may also be selected not by the electronic device of the original cell, but by the electronic device of the target cell.

Next, in step S1403, the electronic device determines whether the measurement report satisfies the cell handover condition based on the measurement report received from one or more terminal devices in the terminal device group. When the measurement report satisfies the cell switching condition ("Yes" in step S1403), in step S1404, the electronic device sends a cell switching request of the terminal device group to another electronic device serving the target cell. Conversely, when the measurement report does not meet the cell handover condition ("No" in step S1403), the electronic device returns to make a judgment based on the newly received measurement report.

In some embodiments, when the reference signal received power RSRP predicted by the terminal device in the target cell exceeds the RSRP predicted in the original cell by a predetermined threshold, the electronic device transmits the cell of the terminal device group to another electronic device serving the target cell Switch request. In some embodiments, the electronic device uses the currently measured RSRP, the RSRP change slope, and the lead time to calculate the predicted RSRP of the terminal device in the original cell and the target cell. In some embodiments, the electronic device uses the measured RSRP historical value in the measurement report to fit and estimate the RSRP change slope. In some embodiments, the electronic device configures the lead time based on the measured moving speed of the terminal device.

In some embodiments, the cell handover request of the terminal device group includes the representative terminal device ID selected by the electronic device, that is, the representative terminal device ID recommended to another electronic device in the target cell.

Next, in step S1405, the electronic device receives a cell handover response of the terminal device group from another electronic device in the target cell. When the electronic device receives the cell handover response of the terminal device group from another electronic device in the target cell ("Yes" in step S1405), in step S1406, the electronic device sends a handover command to the terminal device group to instruct the terminal device group Perform cell handover. Conversely, when the electronic device does not receive the cell switching response of the terminal device group from another electronic device in the target cell ("No" in step S1405), the cell switching ends.

In some embodiments, the handover command includes the cell radio network temporary identification C-RNTI of each terminal device in the terminal device group in the target cell.

As mentioned above, other specific details of cell handover have been described, and the description will not be repeated here.

<<4. Application example>>

An example of a high-speed train communication scenario is described in the present disclosure, but it should be understood that the application scenario of the present disclosure is not limited to a high-speed train communication scenario. The improved solution proposed in the present disclosure can be applied to any mobile communication application scenario that has higher requirements on resources and reliability.

It should be noted that the above description is only exemplary. The embodiments of the present disclosure can also be executed in any other suitable manner, and the advantageous effects obtained by the embodiments of the present disclosure can still be achieved. Moreover, the embodiments of the present disclosure can also be applied to other similar application examples, and the advantageous effects obtained by the embodiments of the present disclosure can still be achieved.

It should be understood that the machine-readable storage medium or the machine-executable instructions in the program product according to the embodiments of the present disclosure may be configured to perform operations corresponding to the above-mentioned device and method embodiments. When referring to the above-mentioned device and method embodiments, the embodiment of the machine-readable storage medium or program product is clear to those skilled in the art, so the description will not be repeated. Machine-readable storage media and program products for carrying or including the above-mentioned machine-executable instructions also fall within the scope of the present disclosure. Such storage media may include, but are not limited to, floppy disks, optical disks, magneto-optical disks, memory cards, memory sticks, and so on.

In addition, it should be understood that the aforementioned series of processing and devices can also be implemented by software and/or firmware. In the case of implementation by software and/or firmware, a computer with a dedicated hardware structure, such as a general-purpose personal computer 1500 shown in FIG. 15, is installed from a storage medium or a network to the program constituting the software, and the computer is installed with various programs. When, can perform various functions and so on. FIG. 15 is a block diagram showing an example structure of a personal computer of an information processing apparatus that can be employed in an embodiment of the present disclosure. In an example, the personal computer may correspond to the above-mentioned exemplary terminal device according to the present disclosure.

In FIG. 15, a central processing unit (CPU) 1501 performs various processes in accordance with a program stored in a read only memory (ROM) 1502 or a program loaded from a storage part 1508 to a random access memory (RAM) 1503. The RAM 1503 also stores data required when the CPU 1501 executes various processes and the like as necessary.

The CPU 1501, ROM 1502, and RAM 1503 are connected to each other via a bus 1504. The input/output interface 1505 is also connected to the bus 1504.

The following components are connected to the input/output interface 1505: input part 1506, including keyboard, mouse, etc.; output part 1507, including display, such as cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; storage part 1508 , Including hard disks, etc.; and communication part 1509, including network interface cards such as LAN cards, modems, etc. The communication section 1509 performs communication processing via a network such as the Internet.

The driver 1510 is also connected to the input/output interface 1505 as required. A removable medium 1511 such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc. is mounted on the drive 1510 as needed, so that the computer program read out therefrom is installed into the storage portion 1508 as needed.

In the case of realizing the above-mentioned series of processing by software, a program constituting the software is installed from a network such as the Internet or a storage medium such as a removable medium 1511.

Those skilled in the art should understand that this storage medium is not limited to the detachable medium 1511 shown in FIG. 15 where the program is stored and distributed separately from the device to provide the program to the user. Examples of removable media 1511 include magnetic disks (including floppy disks (registered trademarks)), optical disks (including compact disk read-only memory (CD-ROM) and digital versatile disks (DVD)), magneto-optical disks (including mini disks (MD) (registered trademarks) )) and semiconductor memory. Alternatively, the storage medium may be a ROM 1502, a hard disk included in the storage portion 1508, etc., in which programs are stored and distributed to users together with the devices containing them.

The technology of the present disclosure can be applied to various products.

For example, the electronic device 10/electronic device 30 according to an embodiment of the present disclosure may be implemented as various control devices/base stations or included in various control devices/base stations. For example, the terminal device 20 according to an embodiment of the present disclosure may be implemented as various terminal devices or included in various terminal devices.

For example, the electronic device/base station mentioned in the present disclosure may be implemented as any type of base station, such as an eNB, such as a macro eNB and a small eNB. A small eNB may be an eNB that covers a cell smaller than a macro cell, such as a pico eNB, a micro eNB, and a home (femto) eNB. Also for example, it may be implemented as a gNB, such as a macro gNB and a small gNB. The small gNB may be a gNB covering a cell smaller than a macro cell, such as pico gNB, micro gNB, and home (femto) gNB. Alternatively, the base station may be implemented as any other type of base station, such as NodeB and Base Transceiver Station (BTS). The base station may include: a main body (also referred to as a base station device) configured to control wireless communication; and one or more remote radio heads (Remote Radio Head, RRH) arranged in a different place from the main body. In addition, various types of terminals to be described below can all operate as base stations by temporarily or semi-persistently performing base station functions.

For example, the terminal devices mentioned in the present disclosure may be implemented as mobile terminals (such as smart phones, tablet personal computers (PCs), notebook PCs, portable game terminals, portable/dongle type mobile routers, and mobile routers) in some embodiments. Digital camera) or in-vehicle terminal (such as car navigation equipment). The terminal device may also be implemented as a terminal (also referred to as a machine type communication (MTC) terminal) that performs machine-to-machine (M2M) communication. In addition, the terminal device may be a wireless communication module (such as an integrated circuit module including a single chip) installed on each of the above-mentioned terminals.

Hereinafter, an application example according to the present disclosure will be described with reference to FIGS. 16 to 19.

[Example of base station]

It should be understood that the term electronic equipment/base station in the present disclosure has the full breadth of its usual meaning, and at least includes wireless communication stations used as a wireless communication system or a part of a radio system to facilitate communication. Examples of the base station may be, for example, but not limited to the following: the base station may be one or both of a base transceiver station (BTS) and a base station controller (BSC) in a GSM system, and may be a radio network controller in a WCDMA system One or both of (RNC) and Node B may be eNBs in LTE and LTE-Advanced systems, or may be corresponding network nodes in future communication systems (for example, gNB, eLTE that may appear in 5G communication systems) eNB, etc.). Part of the functions in the base station of the present disclosure may also be implemented as an entity having a communication control function in D2D, M2M, and V2V communication scenarios, or as an entity that plays a role of spectrum coordination in a cognitive radio communication scenario.

First example

FIG. 16 is a block diagram showing a first example of a schematic configuration of an eNB to which the technology of the present disclosure can be applied. The eNB 1600 includes multiple antennas 1610 and base station equipment 1620. The base station device 1620 and each antenna 1610 may be connected to each other via an RF cable. In an implementation manner, the eNB 1600 (or base station device 1620) herein may correspond to the electronic device 10 or the electronic device 30 described above.

Each of the antennas 1610 includes a single or multiple antenna elements (such as multiple antenna elements included in a multiple input multiple output (MIMO) antenna), and is used for the base station device 1620 to transmit and receive wireless signals. As shown in FIG. 16, the eNB 1600 may include multiple antennas 1610. For example, multiple antennas 1610 may be compatible with multiple frequency bands used by eNB 1600.

The base station device 1620 includes a controller 1621, a memory 1622, a network interface 1623, and a wireless communication interface 1625.

The controller 1621 may be, for example, a CPU or a DSP, and operates various functions of a higher layer of the base station device 1620. For example, the controller 1621 triggers the cell handover according to the measurement report on the terminal side in the wireless communication system acquired by the wireless communication interface 1625, so that the terminal device group uses one of the terminal devices as the representative terminal device, and the group is taken from the original cell. Switch to the target cell. The controller 1621 may have a logic function to perform control such as radio resource control, radio bearer control, mobility management, access control, and scheduling. This control can be performed in conjunction with nearby eNBs or core network nodes. The memory 1622 includes RAM and ROM, and stores programs executed by the controller 1621 and various types of control data (such as switching permission data and switching command data).

The network interface 1623 is a communication interface for connecting the base station device 1620 to the core network 1624. The controller 1621 may communicate with a core network node or another eNB via a network interface 1623. In this case, the eNB 1600 and the core network node or other eNBs may be connected to each other through a logical interface (such as an S1 interface and an X2 interface). The network interface 1623 may also be a wired communication interface or a wireless communication interface for a wireless backhaul line. If the network interface 1623 is a wireless communication interface, the network interface 1623 can use a higher frequency band for wireless communication than the frequency band used by the wireless communication interface 1625.

The wireless communication interface 1625 supports any cellular communication scheme (such as Long Term Evolution (LTE) and LTE-Advanced), and provides wireless connection to a terminal located in a cell of the eNB 1600 via an antenna 1610. The wireless communication interface 1625 may generally include, for example, a baseband (BB) processor 1626 and an RF circuit 1627. The BB processor 1626 can perform, for example, encoding/decoding, modulation/demodulation, and multiplexing/demultiplexing, and perform layers (such as L1, medium access control (MAC), radio link control (RLC), and packet data convergence protocol ( PDCP)) various types of signal processing. Instead of the controller 1621, the BB processor 1626 may have a part or all of the above-mentioned logical functions. The BB processor 1626 may be a memory storing a communication control program, or a module including a processor and related circuits configured to execute the program. The update program can change the function of the BB processor 1626. The module may be a card or a blade inserted into the slot of the base station device 1620. Alternatively, the module can also be a chip mounted on a card or blade. Meanwhile, the RF circuit 1627 may include, for example, a mixer, a filter, and an amplifier, and transmit and receive wireless signals via the antenna 1610. Although FIG. 16 shows an example in which one RF circuit 1627 is connected to one antenna 1610, the present disclosure is not limited to this illustration, but one RF circuit 1627 can connect multiple antennas 1610 at the same time.

As shown in FIG. 16, the wireless communication interface 1625 may include a plurality of BB processors 1626. For example, multiple BB processors 1626 may be compatible with multiple frequency bands used by eNB 1600. As shown in FIG. 16, the wireless communication interface 1625 may include a plurality of RF circuits 1627. For example, multiple RF circuits 1627 may be compatible with multiple antenna elements. Although FIG. 16 shows an example in which the wireless communication interface 1625 includes a plurality of BB processors 1626 and a plurality of RF circuits 1627, the wireless communication interface 1625 may also include a single BB processor 1626 or a single RF circuit 1627.

Second example

FIG. 17 is a block diagram showing a second example of a schematic configuration of an eNB to which the technology of the present disclosure can be applied. The eNB 1700 includes multiple antennas 1710, RRHs 1720, and base station equipment 1730. The RRH 1720 and each antenna 1710 may be connected to each other via an RF cable. The base station device 1730 and the RRH 1720 may be connected to each other via a high-speed line such as an optical fiber cable. In an implementation manner, the eNB 1700 (or base station device 1730) herein may correspond to the above-mentioned electronic device 10 or electronic device 30.

Each of the antennas 1710 includes a single or multiple antenna elements (such as multiple antenna elements included in a MIMO antenna), and is used for the RRH 1720 to transmit and receive wireless signals. As shown in FIG. 17, the eNB 1700 may include multiple antennas 1710. For example, multiple antennas 1710 may be compatible with multiple frequency bands used by eNB 1700.

The base station equipment 1730 includes a controller 1731, a memory 1732, a network interface 1733, a wireless communication interface 1734, and a connection interface 1736. The controller 1731, the memory 1732, and the network interface 1733 are the same as the controller 1621, the memory 1622, and the network interface 1623 described with reference to FIG. 16.

The wireless communication interface 1734 supports any cellular communication scheme (such as LTE and LTE-Advanced), and provides wireless communication to terminals located in the sector corresponding to the RRH 1720 via the RRH 1720 and the antenna 1710. The wireless communication interface 1734 may generally include, for example, a BB processor 1735. The BB processor 1735 is the same as the BB processor 1626 described with reference to FIG. 16 except that the BB processor 1735 is connected to the RF circuit 1722 of the RRH 1720 via the connection interface 1736. As shown in FIG. 17, the wireless communication interface 1734 may include a plurality of BB processors 1735. For example, multiple BB processors 1735 may be compatible with multiple frequency bands used by the eNB 1700. Although FIG. 17 shows an example in which the wireless communication interface 1734 includes a plurality of BB processors 1735, the wireless communication interface 1734 may also include a single BB processor 1735.

The connection interface 1736 is an interface for connecting the base station device 1730 (wireless communication interface 1734) to the RRH 1720. The connection interface 1736 may also be a communication module used to connect the base station device 1730 (wireless communication interface 1734) to the RRH 1720 for communication in the aforementioned high-speed line.

The RRH 1720 includes a connection interface 1723 and a wireless communication interface 1721.

The connection interface 1723 is an interface for connecting the RRH 1720 (wireless communication interface 1721) to the base station device 1730. The connection interface 1723 may also be a communication module used for communication in the above-mentioned high-speed line.

The wireless communication interface 1721 transmits and receives wireless signals via the antenna 1710. The wireless communication interface 1721 may generally include, for example, an RF circuit 1722. The RF circuit 1722 may include, for example, a mixer, a filter, and an amplifier, and transmit and receive wireless signals via the antenna 1710. Although FIG. 17 shows an example in which one RF circuit 1722 is connected to one antenna 1710, the present disclosure is not limited to this illustration, but one RF circuit 1722 can connect multiple antennas 1710 at the same time.

As shown in FIG. 17, the wireless communication interface 1721 may include a plurality of RF circuits 1722. For example, multiple RF circuits 1722 may support multiple antenna elements. Although FIG. 17 shows an example in which the wireless communication interface 1721 includes a plurality of RF circuits 1722, the wireless communication interface 1721 may also include a single RF circuit 1722.

[Example of user equipment]

First example

FIG. 18 is a block diagram showing an example of a schematic configuration of a smart phone 1800 to which the technology of the present disclosure can be applied. The smart phone 1800 includes a processor 1801, a memory 1802, a storage device 1803, an external connection interface 1804, a camera device 1806, a sensor 1807, a microphone 1808, an input device 1809, a display device 1810, a speaker 1811, a wireless communication interface 1812, one or more An antenna switch 1815, one or more antennas 1816, a bus 1817, a battery 1818, and an auxiliary controller 1819. In an implementation manner, the smart phone 1800 (or the processor 1801) herein may correspond to the aforementioned terminal device 20.

The processor 1801 may be, for example, a CPU or a system on a chip (SoC), and controls the functions of the application layer and other layers of the smart phone 1800. The memory 1802 includes RAM and ROM, and stores data and programs executed by the processor 1801. The storage device 1803 may include a storage medium such as a semiconductor memory and a hard disk. The external connection interface 1804 is an interface for connecting an external device such as a memory card and a universal serial bus (USB) device to the smart phone 1800.

The imaging device 1806 includes an image sensor such as a charge coupled device (CCD) and a complementary metal oxide semiconductor (CMOS), and generates a captured image. The sensor 1807 may include a group of sensors, such as a measurement sensor, a gyroscope sensor, a geomagnetic sensor, and an acceleration sensor. The microphone 1808 converts the sound input to the smart phone 1800 into an audio signal. The input device 1809 includes, for example, a touch sensor, a keypad, a keyboard, a button, or a switch configured to detect a touch on the screen of the display device 1810, and receives an operation or information input from the user. The display device 1810 includes a screen such as a liquid crystal display (LCD) and an organic light emitting diode (OLED) display, and displays an output image of the smartphone 1800. The speaker 1811 converts the audio signal output from the smart phone 1800 into sound.

The wireless communication interface 1812 supports any cellular communication scheme such as LTE and LTE-Advanced, and performs wireless communication. The wireless communication interface 1812 may generally include, for example, a BB processor 1813 and an RF circuit 1814. The BB processor 1813 may perform, for example, encoding/decoding, modulation/demodulation, and multiplexing/demultiplexing, and perform various types of signal processing for wireless communication. Meanwhile, the RF circuit 1814 may include, for example, a mixer, a filter, and an amplifier, and transmit and receive wireless signals via the antenna 1816. The wireless communication interface 1812 may be a chip module on which the BB processor 1813 and the RF circuit 1814 are integrated. As shown in FIG. 18, the wireless communication interface 1812 may include a plurality of BB processors 1813 and a plurality of RF circuits 1814. Although FIG. 18 shows an example in which the wireless communication interface 1812 includes a plurality of BB processors 1813 and a plurality of RF circuits 1814, the wireless communication interface 1812 may also include a single BB processor 1813 or a single RF circuit 1814.

In addition, in addition to the cellular communication scheme, the wireless communication interface 1812 may support another type of wireless communication scheme, such as a short-range wireless communication scheme, a near field communication scheme, and a wireless local area network (LAN) scheme. In this case, the wireless communication interface 1812 may include a BB processor 1813 and an RF circuit 1814 for each wireless communication scheme.

Each of the antenna switches 1815 switches the connection destination of the antenna 1816 among a plurality of circuits included in the wireless communication interface 1812 (for example, circuits for different wireless communication schemes).

Each of the antennas 1816 includes a single or multiple antenna elements (such as multiple antenna elements included in a MIMO antenna), and is used for the wireless communication interface 1812 to transmit and receive wireless signals. As shown in FIG. 18, the smart phone 1800 may include multiple antennas 1816. Although FIG. 18 shows an example in which the smart phone 1800 includes a plurality of antennas 1816, the smart phone 1800 may also include a single antenna 1816.

In addition, the smart phone 1800 may include an antenna 1816 for each wireless communication scheme. In this case, the antenna switch 1815 may be omitted from the configuration of the smart phone 1800.

The bus 1817 connects the processor 1801, the memory 1802, the storage device 1803, the external connection interface 1804, the camera device 1806, the sensor 1807, the microphone 1808, the input device 1809, the display device 1810, the speaker 1811, the wireless communication interface 1812, and the auxiliary controller 1819 to each other. connection. The battery 1818 supplies power to each block of the smart phone 1800 shown in FIG. 18 via a feeder line, and the feeder line is partially shown as a dashed line in the figure. The auxiliary controller 1819 operates the minimum necessary functions of the smartphone 1800 in the sleep mode, for example.

Second example

FIG. 19 is a block diagram showing an example of a schematic configuration of a car navigation device 1900 to which the technology of the present disclosure can be applied. The car navigation device 1900 includes a processor 1901, a memory 1902, a global positioning system (GPS) module 1904, a sensor 1905, a data interface 1906, a content player 1907, a storage medium interface 1908, an input device 1909, a display device 1910, a speaker 1911, a wireless A communication interface 1913, one or more antenna switches 1916, one or more antennas 1917, and a battery 1918. In an implementation manner, the car navigation device 1900 (or the processor 1901) herein may correspond to the terminal device 20.

The processor 1901 may be, for example, a CPU or SoC, and controls the navigation function and other functions of the car navigation device 1900. The memory 1902 includes RAM and ROM, and stores data and programs executed by the processor 1901.

The GPS module 1904 uses GPS signals received from GPS satellites to measure the position of the car navigation device 1900 (such as latitude, longitude, and altitude). The sensor 1905 may include a group of sensors, such as a gyroscope sensor, a geomagnetic sensor, and an air pressure sensor. The data interface 1906 is connected to, for example, an in-vehicle network 1921 via a terminal not shown, and acquires data (such as vehicle speed data) generated by the vehicle.

The content player 1907 reproduces content stored in a storage medium such as CD and DVD, which is inserted into the storage medium interface 1908. The input device 1909 includes, for example, a touch sensor, a button, or a switch configured to detect a touch on the screen of the display device 1910, and receives an operation or information input from the user. The display device 1910 includes a screen such as an LCD or OLED display, and displays an image of a navigation function or reproduced content. The speaker 1911 outputs the sound of the navigation function or the reproduced content.

The wireless communication interface 1913 supports any cellular communication scheme such as LTE and LTE-Advanced, and performs wireless communication. The wireless communication interface 1913 may generally include, for example, a BB processor 1914 and an RF circuit 1915. The BB processor 1914 may perform, for example, encoding/decoding, modulation/demodulation, and multiplexing/demultiplexing, and perform various types of signal processing for wireless communication. Meanwhile, the RF circuit 1915 may include, for example, a mixer, a filter, and an amplifier, and transmit and receive wireless signals via an antenna 1917. The wireless communication interface 1913 can also be a chip module on which the BB processor 1914 and the RF circuit 1915 are integrated. As shown in FIG. 19, the wireless communication interface 1913 may include a plurality of BB processors 1914 and a plurality of RF circuits 1915. Although FIG. 19 shows an example in which the wireless communication interface 1913 includes a plurality of BB processors 1914 and a plurality of RF circuits 1915, the wireless communication interface 1913 may also include a single BB processor 1914 or a single RF circuit 1915.

In addition, in addition to the cellular communication scheme, the wireless communication interface 1913 may support another type of wireless communication scheme, such as a short-range wireless communication scheme, a near field communication scheme, and a wireless LAN scheme. In this case, the wireless communication interface 1913 may include a BB processor 1914 and an RF circuit 1915 for each wireless communication scheme.

Each of the antenna switches 1916 switches the connection destination of the antenna 1917 among a plurality of circuits included in the wireless communication interface 1913, such as circuits for different wireless communication schemes.

Each of the antennas 1917 includes a single or multiple antenna elements (such as multiple antenna elements included in a MIMO antenna), and is used for the wireless communication interface 1913 to transmit and receive wireless signals. As shown in FIG. 19, the car navigation device 1900 may include a plurality of antennas 1917. Although FIG. 19 shows an example in which the car navigation device 1900 includes a plurality of antennas 1917, the car navigation device 1900 may also include a single antenna 1917.

In addition, the car navigation device 1900 may include an antenna 1917 for each wireless communication scheme. In this case, the antenna switch 1916 may be omitted from the configuration of the car navigation device 1900.

The battery 1918 supplies power to each block of the car navigation device 1900 shown in FIG. 19 via a feeder line, and the feeder line is partially shown as a dashed line in the figure. The battery 1918 accumulates electric power supplied from the vehicle.

The technology of the present disclosure can also be implemented as an in-vehicle system (or vehicle) 1920 including one or more blocks in a car navigation device 1900, an in-vehicle network 1921, and a vehicle module 1922. The vehicle module 1922 generates vehicle data (such as vehicle speed, engine speed, and failure information), and outputs the generated data to the vehicle network 1921.

<<5. Conclusion>>

The embodiments of the present disclosure have been described in detail above with reference to FIGS. 1 to 19. As described above, the electronic device according to the embodiment of the present disclosure can perform cell switching for terminal devices on high-speed vehicles based on the packet-based cell switching technology and the predicted-based cell switching technology. According to the embodiments of the present disclosure, users on high-speed vehicles can be accurately identified, and the users on high-speed vehicles can be handed over in groups at the same time, which significantly improves the handover speed, and only one representative user is selected in each group For random access, the design of grouped cell switching requests and cell switching responses significantly reduces the resource overhead when a large number of users perform cell switching at the same time, and also reduces the probability and probability of random access conflicts when a large number of users perform cell switching at the same time. Handover delay. In addition, cell handover can be triggered in advance based on prediction, thereby effectively reducing the probability of handover failure. Furthermore, the present disclosure also proposes a scheme of reserving only the preamble sequence corresponding to a part of the SSB, thereby further reducing the resource overhead in the cell handover process.

The exemplary embodiments of the present disclosure have been described above with reference to the accompanying drawings, but the present disclosure is of course not limited to the above examples. Those skilled in the art can get various changes and modifications within the scope of the appended claims, and it should be understood that these changes and modifications will naturally fall within the technical scope of the present disclosure.

In addition, it should be understood that the aforementioned series of processing and devices can also be implemented by software and/or firmware. In the case of implementation by software and/or firmware, a corresponding program constituting the corresponding software is stored in the storage medium of the related device, and when the program is executed, various functions can be performed.

For example, a plurality of functions included in one unit in the above embodiments may be realized by separate devices. Alternatively, the multiple functions implemented by multiple units in the above embodiments may be implemented by separate devices, respectively. In addition, one of the above functions can be implemented by multiple units. Needless to say, such a configuration is included in the technical scope of the present disclosure.

In this specification, the steps described in the flowchart include not only processing performed in time series in the described order, but also processing performed in parallel or individually rather than necessarily in time series. In addition, even in the steps processed in time series, needless to say, the order can be changed appropriately.

Implementation of exemplary embodiments of the present disclosure

According to the embodiments of the present disclosure, various implementation manners for realizing the concept of the present disclosure can be conceived, including but not limited to:

Exemplary embodiment 1. An electronic device used on the control side of a wireless communication system, comprising a processing circuit configured to:

Select a representative terminal device from the multiple terminal devices in the terminal device group, so that the terminal device group can use the representative terminal device as a representative of the terminal device group, and switch from the original cell to the electronic device to serve in the group unit. The target cell.

Exemplary embodiment 2. The electronic device of exemplary embodiment 1, wherein

The representative terminal device is reserved for non-competitive random access resources.

Exemplary embodiment 3. The electronic device of exemplary embodiment 1, wherein

Each terminal device in the terminal device group has the same or similar signal spatial characteristics.

Exemplary embodiment 4. The electronic device of exemplary embodiment 3, wherein

In the case where the terminal equipment has been grouped in the original cell, another electronic device accessed by the terminal equipment in the original cell removes the difference in signal spatial characteristics between the original terminal equipment group and other terminal equipment in the group. A large terminal device is added, and a new terminal device similar to the signal space characteristics of the terminal device in the group is added to obtain the terminal device group.

Exemplary embodiment 5. The electronic device of exemplary embodiment 3, wherein

In the case that the terminal device is not grouped in the original cell, another electronic device accessed by the terminal device in the original cell obtains the terminal device group by clustering the signal spatial characteristics.

Exemplary Embodiment 6. The electronic device of any one of Exemplary Embodiments 3-5, wherein

The signal spatial characteristics include one or more of the following: downlink transmission beam, direct beam angle, Doppler frequency shift, path loss, and cell switching history.

Exemplary embodiment 7. The electronic device of exemplary embodiment 1, wherein the processing circuit is further configured to:

Receiving a cell handover request of the terminal device group from another electronic device accessed by the terminal device in the original cell.

Exemplary embodiment 8. The electronic device of exemplary embodiment 7, wherein the processing circuit is further configured to:

The representative terminal device is selected based on the representative terminal device ID recommended by the another electronic device included in the cell handover request of the terminal device group.

Exemplary embodiment 9. The electronic device of exemplary embodiment 1, wherein the processing circuit is further configured to:

Randomly select the representative terminal device.

Exemplary embodiment 10. The electronic device of exemplary embodiment 7, wherein

The cell handover request of the terminal equipment group includes terminal equipment specific information, and the terminal equipment specific information includes the timing advance TA value of each terminal equipment in the terminal equipment group in the original cell.

Exemplary embodiment 11. The electronic device of exemplary embodiment 7, wherein the processing circuit is further configured to:

In response to the cell switching request of the terminal device group, a cell switching response of the terminal device group is sent to the other electronic device.

Exemplary embodiment 12. The electronic device of exemplary embodiment 11, wherein

The cell handover response of the terminal equipment group includes terminal equipment-specific information, and the terminal equipment-specific information includes the ID of one or more terminal equipment that is permitted to switch, the ID of the selected representative terminal equipment, and the ID of the representative terminal equipment. Configuration information of reserved non-competitive random access resources.

Exemplary embodiment 13. The electronic device of exemplary embodiment 11, wherein

The cell handover response of the terminal equipment group includes the cell radio network temporary identification C-RNTI of each terminal equipment in the target cell.

Exemplary embodiment 14. The electronic device of exemplary embodiment 11, wherein

In response to the cell handover reply of the terminal device group, the other electronic device sends a handover command to the terminal device group; and

In response to the handover command, all terminal devices in the terminal device group cut off the connection with the original cell, and perform downlink synchronization to the target cell.

Exemplary embodiment 15. The electronic device of exemplary embodiment 14, wherein

The handover command includes a random access indicator indicating whether the terminal device is a representative terminal device.

Exemplary embodiment 16. The electronic device of exemplary embodiment 14, wherein

For the representative terminal device, the handover command includes configuration information of non-competitive random access resources reserved by the electronic device for the representative terminal device.

Exemplary embodiment 17. The electronic device of exemplary embodiment 2, wherein

The representative terminal device uses the reserved non-competitive random access resources to randomly access the electronic device in the target cell; and

The electronic device sends a random access response RAR to all terminal devices in the terminal device group.

Exemplary embodiment 18. The electronic device of exemplary embodiment 2, wherein

The representative terminal device uses the reserved non-competitive random access resource to send a preamble sequence to the electronic device, thereby accessing the electronic device in the target cell.

Exemplary embodiment 19. The electronic device of exemplary embodiment 18, wherein

The time from receiving the handover command to sending the preamble sequence of the representative terminal device is greater than or equal to the predetermined group waiting window time.

Exemplary embodiment 20. The electronic device of exemplary embodiment 18, wherein the processing circuit is further configured to:

Based on the preamble sequence, a TA value representing the timing advance of the terminal equipment in the target cell is obtained.

Exemplary embodiment 21. The electronic device of exemplary embodiment 20, wherein the processing circuit is further configured to:

Calculating the amount of change in the TA value of the representative terminal equipment in the original cell and the target cell; and

The TA value of the non-representative terminal device in the target cell is obtained by adding the TA value of the non-representative terminal device in the original cell and the change amount of the TA value of the representative terminal device in the terminal device group.

Exemplary embodiment 22. The electronic device of exemplary embodiment 18, wherein the processing circuit is further configured to:

Based on the preamble sequence, the optimal downlink transmission beam representing the terminal equipment in the target cell is obtained.

Exemplary embodiment 23. The electronic device of exemplary embodiment 17, wherein the processing circuit is further configured to:

The RAR to be sent to the non-representative terminal device is scrambled by using the cell radio network temporary identification C-RNTI of the target cell of the non-representative terminal device.

Exemplary embodiment 24. The electronic device of exemplary embodiment 17, wherein

After completing the downlink synchronization, the non-representative terminal device continuously detects the RAR.

Exemplary embodiment 25. The electronic device of exemplary embodiment 17, wherein the processing circuit is further configured to:

Utilize the uplink transmission resources indicated in the RAR to receive handover completion signaling from the terminal device that successfully detects the RAR.

Exemplary embodiment 26. The electronic device of exemplary embodiment 7, wherein

The cell handover request of the terminal device group is triggered by measurement reports of one or more terminal devices in the terminal device group.

Exemplary embodiment 27. The electronic device of exemplary embodiment 7, wherein

When the reference signal received power RSRP predicted by the terminal device in the target cell exceeds the RSRP predicted in its original cell by a predetermined threshold, the cell handover request of the terminal device group is triggered.

Exemplary embodiment 28. The electronic device of exemplary embodiment 27, wherein

The predicted RSRP of the terminal equipment in the original cell and the target cell is calculated by using the currently measured RSRP, the slope of the RSRP change, and the lead time.

Exemplary embodiment 29. The electronic device of exemplary embodiment 28, wherein

The RSRP change slope is estimated by fitting the measured RSRP historical value.

Exemplary embodiment 30. The electronic device of exemplary embodiment 28, wherein

The advance time is the difference between the predicted time and the current time.

Exemplary embodiment 31. The electronic device of exemplary embodiment 28, wherein

The lead time is configured based on the measured moving speed of the terminal device.

Exemplary embodiment 32. The electronic device of exemplary embodiment 1, wherein

Only the representative terminal device reserves the preamble sequence resources corresponding to a part of the downlink transmission beams in the downlink transmission beams of the electronic device used to transmit the synchronization signal block SSB.

Exemplary embodiment 33. A terminal device used in a terminal side of a wireless communication system, the terminal device including a processing circuit configured to:

Trigger the electronic device on the control side of the wireless communication system serving the terminal device to send the cell handover request of the terminal device group including the terminal device and receive the cell handover response of the corresponding terminal device group, so that the terminal device group is As a representative terminal device, a terminal device is handed over from the original cell served by the electronic device to the target cell in a group unit.

Exemplary embodiment 34. The terminal device of exemplary embodiment 33, wherein the processing circuit is further configured to:

When the terminal device moves along a specific trajectory and the moving speed is greater than a specific threshold, and the measurement report satisfies the cell handover condition, trigger the electronic device to send a cell handover request of the terminal device group.

Exemplary embodiment 35. The terminal device of exemplary embodiment 33, wherein the processing circuit is further configured to:

Receiving a measurement control command from the electronic device; and

Perform measurement in response to the measurement control command, and send a measurement report to the electronic device.

Exemplary embodiment 36. The terminal device of exemplary embodiment 33, wherein

The terminal equipment is grouped by the electronic equipment according to its signal spatial characteristics and cell handover history.

Exemplary embodiment 37. The terminal device of exemplary embodiment 36, wherein

The signal spatial characteristics are estimated by the electronic device based on the uplink reference signal sent by the terminal device.

Exemplary embodiment 38. The terminal device of exemplary embodiment 36, wherein

The cell handover history is obtained by inquiring from the mobility management unit by the electronic device.

Exemplary embodiment 39. The terminal device of exemplary embodiment 36, wherein

Terminal devices with the same or similar signal spatial characteristics are grouped together.

Exemplary embodiment 40. The terminal device of exemplary embodiment 33, wherein

The terminal device group includes one representative terminal device and one or more non-representative terminal devices.

Exemplary embodiment 41. The terminal device of exemplary embodiment 33, wherein the processing circuit is further configured to:

Receive a switching command from the electronic device.

Exemplary embodiment 42. The terminal device according to exemplary embodiment 41, wherein the processing circuit is further configured to:

In response to the handover command, the terminal device cuts off the connection with the original cell and performs downlink synchronization on the target cell.

Exemplary embodiment 43. The terminal device of exemplary embodiment 33, wherein the processing circuit is further configured to:

When the terminal device is a representative terminal device, use the reserved non-competitive random access resources to randomly access another electronic device in the target cell; and

Receiving a random access response RAR from the another electronic device.

Exemplary embodiment 44. The terminal device of exemplary embodiment 43, wherein the processing circuit is further configured to:

When the terminal device is a representative terminal device, the reserved non-competitive random access resource is used to send a preamble sequence to the other electronic device in the target cell, so as to access the other electronic device in the target cell.

Exemplary embodiment 45. The terminal device of exemplary embodiment 43, wherein

When the terminal device is a non-representative terminal device, the terminal device continuously detects the random access response RAR after completing the downlink synchronization.

Exemplary embodiment 46. The terminal device of exemplary embodiment 43, wherein the processing circuit is further configured to:

When the terminal device successfully detects the RAR, the uplink transmission resource indicated in the RAR is used to send the handover completion signaling to another electronic device to be accessed by the terminal device in the target cell.

Exemplary embodiment 47. An electronic device used on the control side of a wireless communication system, the electronic device comprising a processing circuit configured to:

Send the cell handover request of the terminal device group to another electronic device in the target cell and receive the cell handover response of the terminal device group from the other electronic device, so that the terminal device group uses one of the terminal devices as the representative terminal device , Switching from the original cell served by the electronic device to the target cell in a group unit.

Exemplary embodiment 48. The electronic device of exemplary embodiment 47, wherein the processing circuit is further configured to:

The terminal devices it serves are grouped into one or more terminal device groups, where each terminal device group includes a representative terminal device and one or more non-representative terminal devices.

Exemplary embodiment 49. The electronic device of exemplary embodiment 48, wherein the processing circuit is further configured to:

According to the signal space characteristics of the terminal equipment and the cell handover history, the terminal equipment is grouped.

Exemplary embodiment 50. The electronic device of exemplary embodiment 47, wherein the processing circuit is further configured to:

Send a cell handover history query command to the mobile management unit; and

Receive the cell handover history of the terminal device from the mobility management unit.

Exemplary embodiment 51. The electronic device of exemplary embodiment 47, wherein the processing circuit is further configured to:

Receive the uplink reference signal from the terminal equipment; and

Based on the received uplink reference signal, the signal spatial characteristics of the terminal equipment are estimated.

Exemplary embodiment 52. The electronic device of exemplary embodiment 48, wherein the processing circuit is further configured to:

When the terminal devices are not grouped originally, by clustering the signal spatial characteristics, the terminal devices with the same or similar signal spatial characteristics are grouped into a group; and

When the terminal equipment has been grouped, the terminal equipment in the original terminal equipment group that is significantly different from the other terminal equipment in the group is removed, and a new terminal equipment that is similar to the signal space characteristic of the terminal equipment in the group is added. , Get a new terminal equipment group.

Exemplary embodiment 53. The electronic device of exemplary embodiment 47, wherein the processing circuit is further configured to:

Receive measurement reports from one or more terminal devices in the terminal device group; and

When the measurement report satisfies the cell handover condition, a cell handover request of the terminal device group is sent to the other electronic device serving the target cell.

Exemplary embodiment 54. The electronic device of exemplary embodiment 47, wherein

The cell handover request of the terminal device group includes a representative terminal device ID recommended by the electronic device to the other electronic device.

Exemplary embodiment 55. The electronic device of exemplary embodiment 47, wherein the processing circuit is further configured to:

The representative terminal device is selected according to the characteristics of the terminal device, and the selected representative terminal device ID is sent to the other electronic device.

Exemplary embodiment 56. The electronic device of exemplary embodiment 47, wherein the processing circuit is further configured to:

In response to the cell handover reply of the terminal equipment group, a handover command is sent to the terminal equipment group.

Exemplary embodiment 57. The electronic device of exemplary embodiment 56, wherein

The handover command includes the cell radio network temporary identification C-RNTI of each terminal device in the target cell.

Exemplary embodiment 58. The electronic device of exemplary embodiment 47, wherein the processing circuit is further configured to:

When the reference signal received power RSRP predicted by the terminal device in the target cell exceeds the RSRP predicted in the original cell by a predetermined threshold, a cell handover request of the terminal device group is sent to another electronic device serving the target cell.

Exemplary embodiment 59. The electronic device of exemplary embodiment 58, wherein the processing circuit is further configured to:

Using the currently measured RSRP, RSRP change slope and lead time, the predicted RSRP of the terminal equipment in the original cell and the target cell is calculated.

Exemplary embodiment 60. The electronic device of exemplary embodiment 59, wherein the processing circuit is further configured to:

The measured RSRP historical value is used to fit and estimate the slope of the RSRP change.

Exemplary embodiment 61. The electronic device of exemplary embodiment 59, wherein the processing circuit is further configured to:

Configure the lead time based on the measured moving speed of the terminal device.

Exemplary embodiment 62. A packet-based cell handover method used in an electronic device on the control side of a wireless communication system, including:

Exemplary embodiment 63. A packet-based cell handover method used in a terminal device on the terminal side of a wireless communication system, including:

Exemplary embodiment 64. A packet-based cell handover method used in an electronic device on the control side of a wireless communication system, including:

Exemplary embodiment 65. A non-transitory computer-readable storage medium having instructions stored thereon, which, when executed by a processor, cause the processor to perform the following operations:

A representative terminal device is selected from a plurality of terminal devices in the terminal device group, so that the terminal device group can use the representative terminal device as a representative of the terminal device group to switch from the original cell to the target cell on a group basis.

Exemplary embodiment 66. A non-transitory computer-readable storage medium having instructions stored thereon, which, when executed by a processor, cause the processor to perform the following operations:

Exemplary embodiment 67. A non-transitory computer-readable storage medium having instructions stored thereon, which, when executed by a processor, cause the processor to perform the following operations:

Send the cell handover request of the terminal device group to another electronic device in the target cell and receive the cell handover response of the terminal device group from the other electronic device, so that the terminal device group uses one of the terminal devices as the representative terminal device , Handover from the original cell to the target cell by group.

Exemplary embodiment 68. A device including a processor and a non-transitory computer-readable storage medium storing instructions that, when executed by the processor, enables the device to perform the method described in the present disclosure .

Exemplary embodiment 69. An apparatus including components for performing the methods described in this disclosure.

Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made without departing from the spirit and scope of the present disclosure as defined by the appended claims. Moreover, the terms "include", "include", or any other variations thereof in the embodiments of the present disclosure are intended to cover non-exclusive inclusion, so that a process, method, article, or device including a series of elements not only includes those elements, but also Including other elements that are not explicitly listed, or elements inherent to the process, method, article, or equipment. If there are no more restrictions, the element defined by the sentence "including a..." does not exclude the existence of other identical elements in the process, method, article, or equipment that includes the element.

Claims

An electronic device used on the control side of a wireless communication system includes a processing circuit configured to:

Select a representative terminal device from the multiple terminal devices in the terminal device group, so that the terminal device group can use the representative terminal device as a representative of the terminal device group, and switch from the original cell to the electronic device to serve in the group unit. The target cell.
The electronic device according to claim 1, wherein

The representative terminal device is reserved for non-competitive random access resources.
The electronic device according to claim 1, wherein

Each terminal device in the terminal device group has the same or similar signal spatial characteristics.
The electronic device according to claim 3, wherein

In the case where the terminal equipment has been grouped in the original cell, another electronic device accessed by the terminal equipment in the original cell removes the difference in signal spatial characteristics between the original terminal equipment group and other terminal equipment in the group. A large terminal device is added, and a new terminal device similar to the signal space characteristics of the terminal device in the group is added to obtain the terminal device group.
The electronic device according to claim 3, wherein

In the case that the terminal device is not grouped in the original cell, another electronic device accessed by the terminal device in the original cell obtains the terminal device group by clustering the signal spatial characteristics.
The electronic device according to any one of claims 3-5, wherein

The signal spatial characteristics include one or more of the following: downlink transmission beam, direct beam angle, Doppler frequency shift, path loss, and cell switching history.
The electronic device of claim 1, wherein the processing circuit is further configured to:

Receiving a cell handover request of the terminal device group from another electronic device accessed by the terminal device in the original cell.
The electronic device according to claim 7, wherein the processing circuit is further configured to:

The representative terminal device is selected based on the representative terminal device ID recommended by the another electronic device included in the cell handover request of the terminal device group.
The electronic device of claim 1, wherein the processing circuit is further configured to:

Randomly select the representative terminal device.
The electronic device according to claim 7, wherein

The cell handover request of the terminal equipment group includes terminal equipment specific information, and the terminal equipment specific information includes the timing advance TA value of each terminal equipment in the terminal equipment group in the original cell.
The electronic device according to claim 7, wherein the processing circuit is further configured to:

In response to the cell switching request of the terminal device group, a cell switching response of the terminal device group is sent to the other electronic device.
The electronic device according to claim 11, wherein

The cell handover response of the terminal equipment group includes terminal equipment-specific information, and the terminal equipment-specific information includes the ID of one or more terminal equipment that is permitted to switch, the ID of the selected representative terminal equipment, and the ID of the representative terminal equipment. Configuration information of reserved non-competitive random access resources.
The electronic device according to claim 11, wherein

The cell handover response of the terminal equipment group includes the cell radio network temporary identification C-RNTI of each terminal equipment in the target cell.
The electronic device according to claim 11, wherein

In response to the cell handover reply of the terminal device group, the other electronic device sends a handover command to the terminal device group; and

In response to the handover command, all terminal devices in the terminal device group cut off the connection with the original cell, and perform downlink synchronization to the target cell.
The electronic device of claim 14, wherein

The handover command includes a random access indicator indicating whether the terminal device is a representative terminal device.
The electronic device of claim 14, wherein

For the representative terminal device, the handover command includes configuration information of non-competitive random access resources reserved by the electronic device for the representative terminal device.
The electronic device according to claim 2, wherein

The representative terminal device uses the reserved non-competitive random access resources to randomly access the electronic device in the target cell; and

The electronic device sends a random access response RAR to all terminal devices in the terminal device group.
The electronic device according to claim 2, wherein

The representative terminal device uses the reserved non-competitive random access resource to send a preamble sequence to the electronic device, thereby accessing the electronic device in the target cell.
The electronic device of claim 18, wherein

The time from receiving the handover command to sending the preamble sequence of the representative terminal device is greater than or equal to the predetermined group waiting window time.
The electronic device of claim 18, wherein the processing circuit is further configured to:

Based on the preamble sequence, a TA value representing the timing advance of the terminal equipment in the target cell is obtained.
The electronic device of claim 20, wherein the processing circuit is further configured to:

Calculating the amount of change in the TA value of the representative terminal equipment in the original cell and the target cell; and

The TA value of the non-representative terminal device in the target cell is obtained by adding the TA value of the non-representative terminal device in the original cell and the change amount of the TA value of the representative terminal device in the terminal device group.
The electronic device of claim 18, wherein the processing circuit is further configured to:

Based on the preamble sequence, the optimal downlink transmission beam representing the terminal equipment in the target cell is obtained.
The electronic device of claim 17, wherein the processing circuit is further configured to:

The RAR to be sent to the non-representative terminal device is scrambled by using the cell radio network temporary identification C-RNTI of the target cell of the non-representative terminal device.
The electronic device according to claim 17, wherein

After completing the downlink synchronization, the non-representative terminal device continuously detects the RAR.
The electronic device of claim 17, wherein the processing circuit is further configured to:

Utilize the uplink transmission resources indicated in the RAR to receive handover completion signaling from the terminal device that successfully detects the RAR.
The electronic device according to claim 7, wherein

The cell handover request of the terminal device group is triggered by measurement reports of one or more terminal devices in the terminal device group.
The electronic device according to claim 7, wherein

When the reference signal received power RSRP predicted by the terminal device in the target cell exceeds the RSRP predicted in its original cell by a predetermined threshold, the cell handover request of the terminal device group is triggered.
The electronic device of claim 27, wherein

The predicted RSRP of the terminal equipment in the original cell and the target cell is calculated by using the currently measured RSRP, the slope of the RSRP change, and the lead time.
The electronic device of claim 28, wherein

The RSRP change slope is estimated by fitting the measured RSRP historical value.
The electronic device of claim 28, wherein

The advance time is the difference between the predicted time and the current time.
The electronic device of claim 28, wherein

The lead time is configured based on the measured moving speed of the terminal device.
The electronic device according to claim 1, wherein

Only the representative terminal device reserves the preamble sequence resources corresponding to a part of the downlink transmission beams in the downlink transmission beams of the electronic device used to transmit the synchronization signal block SSB.
A terminal device used on the terminal side of a wireless communication system, the terminal device including a processing circuit configured to:

Trigger the electronic device on the control side of the wireless communication system serving the terminal device to send the cell handover request of the terminal device group including the terminal device and receive the cell handover response of the corresponding terminal device group, so that the terminal device group is As a representative terminal device, a terminal device is handed over from the original cell served by the electronic device to the target cell in a group unit.
The terminal device of claim 33, wherein the processing circuit is further configured to:

When the terminal device moves along a specific trajectory and the moving speed is greater than a specific threshold, and the measurement report satisfies the cell handover condition, trigger the electronic device to send a cell handover request of the terminal device group.
The terminal device of claim 33, wherein the processing circuit is further configured to:

Receiving a measurement control command from the electronic device; and

Perform measurement in response to the measurement control command, and send a measurement report to the electronic device.
The terminal device according to claim 33, wherein

The terminal equipment is grouped by the electronic equipment according to its signal spatial characteristics and cell handover history.
The terminal device according to claim 36, wherein

The signal spatial characteristics are estimated by the electronic device based on the uplink reference signal sent by the terminal device.
The terminal device according to claim 36, wherein

The cell handover history is obtained by inquiring from the mobility management unit by the electronic device.
The terminal device according to claim 36, wherein

Terminal devices with the same or similar signal spatial characteristics are grouped together.
The terminal device according to claim 33, wherein

The terminal device group includes one representative terminal device and one or more non-representative terminal devices.
The terminal device of claim 33, wherein the processing circuit is further configured to:

Receive a switching command from the electronic device.
The terminal device according to claim 41, wherein the processing circuit is further configured to:

In response to the handover command, the terminal device cuts off the connection with the original cell and performs downlink synchronization on the target cell.
The terminal device of claim 33, wherein the processing circuit is further configured to:

When the terminal device is a representative terminal device, use the reserved non-competitive random access resources to randomly access another electronic device in the target cell; and

Receiving a random access response RAR from the another electronic device.
The terminal device of claim 43, wherein the processing circuit is further configured to:

When the terminal device is a representative terminal device, the reserved non-competitive random access resource is used to send a preamble sequence to the other electronic device in the target cell, so as to access the other electronic device in the target cell.
The terminal device according to claim 43, wherein

When the terminal device is a non-representative terminal device, the terminal device continuously detects the random access response RAR after completing the downlink synchronization.
The terminal device of claim 43, wherein the processing circuit is further configured to:

When the terminal device successfully detects the RAR, the uplink transmission resource indicated in the RAR is used to send the handover completion signaling to another electronic device to be accessed by the terminal device in the target cell.
An electronic device used on the control side of a wireless communication system, the electronic device including a processing circuit configured to:

Send the cell handover request of the terminal device group to another electronic device in the target cell and receive the cell handover response of the terminal device group from the other electronic device, so that the terminal device group uses one of the terminal devices as the representative terminal device , Switching from the original cell served by the electronic device to the target cell in a group unit.
The electronic device of claim 47, wherein the processing circuit is further configured to:

The terminal devices it serves are grouped into one or more terminal device groups, where each terminal device group includes a representative terminal device and one or more non-representative terminal devices.
The electronic device of claim 48, wherein the processing circuit is further configured to:

According to the signal space characteristics of the terminal equipment and the cell handover history, the terminal equipment is grouped.
The electronic device of claim 47, wherein the processing circuit is further configured to:

Send a cell handover history query command to the mobile management unit; and

Receive the cell handover history of the terminal device from the mobility management unit.
The electronic device of claim 47, wherein the processing circuit is further configured to:

Receive the uplink reference signal from the terminal equipment; and

Based on the received uplink reference signal, the signal spatial characteristics of the terminal equipment are estimated.
The electronic device of claim 48, wherein the processing circuit is further configured to:

When the terminal devices are not grouped originally, by clustering the signal spatial characteristics, the terminal devices with the same or similar signal spatial characteristics are grouped into a group; and

When the terminal equipment has been grouped, the terminal equipment in the original terminal equipment group that is significantly different from the other terminal equipment in the group is removed, and a new terminal equipment that is similar to the signal space characteristic of the terminal equipment in the group is added. , Get a new terminal equipment group.
The electronic device of claim 47, wherein the processing circuit is further configured to:

Receive measurement reports from one or more terminal devices in the terminal device group; and

When the measurement report satisfies the cell handover condition, a cell handover request of the terminal device group is sent to the other electronic device serving the target cell.
The electronic device of claim 47, wherein

The cell handover request of the terminal device group includes the representative terminal device ID recommended by the electronic device to the other electronic device.
The electronic device of claim 47, wherein the processing circuit is further configured to:

The representative terminal device is selected according to the characteristics of the terminal device, and the selected representative terminal device ID is sent to the other electronic device.
The electronic device of claim 47, wherein the processing circuit is further configured to:

In response to the cell handover reply of the terminal equipment group, a handover command is sent to the terminal equipment group.
The electronic device of claim 56, wherein

The handover command includes the cell radio network temporary identification C-RNTI of each terminal device in the target cell.
The electronic device of claim 47, wherein the processing circuit is further configured to:

When the reference signal received power RSRP predicted by the terminal device in the target cell exceeds the RSRP predicted in the original cell by a predetermined threshold, a cell handover request of the terminal device group is sent to another electronic device serving the target cell.
The electronic device of claim 58, wherein the processing circuit is further configured to:

Using the currently measured RSRP, RSRP change slope and lead time, the predicted RSRP of the terminal equipment in the original cell and the target cell is calculated.
The electronic device of claim 59, wherein the processing circuit is further configured to:

The measured RSRP historical value is used to fit and estimate the slope of the RSRP change.
The electronic device of claim 59, wherein the processing circuit is further configured to:

Configure the lead time based on the measured moving speed of the terminal device.
A packet-based cell handover method used in electronic equipment on the control side of a wireless communication system includes:

Select a representative terminal device from the multiple terminal devices in the terminal device group, so that the terminal device group can use the representative terminal device as a representative of the terminal device group, and switch from the original cell to the electronic device to serve in the group unit. The target cell.
A packet-based cell handover method used in terminal equipment on the terminal side of a wireless communication system includes:

Trigger the electronic device on the control side of the wireless communication system serving the terminal device to send the cell handover request of the terminal device group including the terminal device and receive the cell handover response of the corresponding terminal device group, so that the terminal device group is As a representative terminal device, a terminal device is handed over from the original cell served by the electronic device to the target cell in a group unit.
A packet-based cell handover method used in electronic equipment on the control side of a wireless communication system includes:

Send the cell handover request of the terminal device group to another electronic device in the target cell and receive the cell handover response of the terminal device group from the other electronic device, so that the terminal device group uses one of the terminal devices as the representative terminal device , Switching from the original cell served by the electronic device to the target cell in a group unit.
A non-transitory computer-readable storage medium on which instructions are stored, which when executed by a processor, cause the processor to perform the following operations:

A representative terminal device is selected from a plurality of terminal devices in the terminal device group, so that the terminal device group can use the representative terminal device as a representative of the terminal device group to switch from the original cell to the target cell on a group basis.
A non-transitory computer-readable storage medium on which instructions are stored, which when executed by a processor, cause the processor to perform the following operations:

Trigger the electronic device on the control side of the wireless communication system serving the terminal device to send the cell handover request of the terminal device group including the terminal device and receive the cell handover response of the corresponding terminal device group, so that the terminal device group is As a representative terminal device, a terminal device is handed over from the original cell served by the electronic device to the target cell in a group unit.
A non-transitory computer-readable storage medium on which instructions are stored, which when executed by a processor, cause the processor to perform the following operations:

Send the cell handover request of the terminal device group to another electronic device in the target cell and receive the cell handover response of the terminal device group from the other electronic device, so that the terminal device group uses one of the terminal devices as the representative terminal device , Handover from the original cell to the target cell by group.
A device comprising a processor and a non-transitory computer-readable storage medium storing instructions, which when executed by the processor enables the device to execute the method according to claim 62, 63 or 64.
A device containing means for performing the method as claimed in claim 62, 63 or 64.