CN114190114A

CN114190114A - Cell reselection method and related communication equipment

Info

Publication number: CN114190114A
Application number: CN202080039552.7A
Authority: CN
Inventors: 刘圆圆; 陈洪强; 韩磊
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-07-13
Filing date: 2020-07-13
Publication date: 2022-03-15
Anticipated expiration: 2040-07-13
Also published as: CN114190114B; WO2022011491A1

Abstract

The embodiment of the application relates to a cell reselection method, which comprises the following steps: for a neighboring cell with a reselection priority higher than the reselection priority of the current serving cell, then: when the signal quality of the current serving cell is higher than or equal to a preset threshold, preventing the cell of the adjacent cell from reselecting and residing in the current serving cell; and when the signal quality of the current serving cell is lower than the preset threshold and the adjacent cell meets the cell reselection condition, initiating cell reselection to the adjacent cell. Based on the cell reselection method, under the condition that the current serving cell is a high-network-standard 5G cell and the adjacent cell is a low-network-standard 4G cell, and under the condition that the signal quality of the current serving cell of the high-network-standard 5G is good, the method can ensure that the UE resides in the current serving cell of the high-network-standard 5G, so that the user experience is improved. The cell reselection method provided by the embodiment of the application can avoid the problem caused by unreasonable cell reselection priorities configured by a system under the condition that the cell reselection priorities configured by the system are not changed.

Description

Cell reselection method and related communication equipment

Technical Field

The present application relates to the field of wireless communications, and in particular, to a cell reselection method and a related communication device.

Background

With the application and development of mobile communication technology, especially with the deployment of 5G, User Equipment (UE) in the market currently supports network systems such as second generation mobile communication technology (2G), third generation mobile communication technology (3G), fourth generation mobile communication technology (4G), and fifth generation mobile communication technology (5G) at the same time.

When the UE is in an idle state in the current serving cell, a cell reselection process can be executed through intra-system cell reselection or cross-system cell reselection so as to reselect a cell with higher priority and better channel quality. Currently, in the cell reselection process, the cell reselection decision is established on the comprehensive consideration of the cell reselection priority and the cell signal quality (RSRP, RSRQ, SINR, etc.). For example, three cell reselection decision strategies are specified in the prior art: (1) if the UE needs to reselect from a serving cell with low reselection priority to an adjacent cell with high reselection priority, the signal quality of the adjacent cell with high reselection priority only needs to be higher than a certain threshold; (2) if the UE needs to select among the cells with the same reselection priority, the signal quality of the adjacent cell is only required to be higher than that of the current service cell; (3) if the UE is to reselect from a serving cell with high reselection priority to a neighboring cell with low reselection priority, the signal quality of the serving cell with high reselection priority is required to be below a certain threshold and the signal quality of the neighboring cell with low reselection priority is required to be above a certain threshold.

For the case where the UE is to reselect from a serving cell of low reselection priority to a neighboring cell of high reselection priority, based on the cell reselection strategy described in (1) above, it is easy to cause the UE to always preferentially camp on the cell of high reselection priority. The user experience is affected if the current high priority cell is not the most desirable cell for the user.

Disclosure of Invention

The present application provides a cell reselection method and related communication device to address at least the above-mentioned shortcomings in the prior art.

According to a first aspect of the present application, there is provided a cell reselection method, wherein for a neighboring cell having a higher reselection priority than a current serving cell, then: when the signal quality of the current serving cell is higher than or equal to a preset threshold, preventing the cell of the adjacent cell from reselecting and residing in the current serving cell; and when the signal quality of the current serving cell is lower than the preset threshold and the adjacent cell meets the cell reselection condition, initiating cell reselection to the adjacent cell.

Based on the cell reselection method, under the condition that the signal quality of the current serving cell is good, the cell is ensured to reside in the current serving cell and not reselect the neighboring cell with the high reselection priority.

Optionally, the neighboring cell is a different-system cell or a same-system different-frequency cell compared to the current serving cell.

Optionally, the current serving cell is a high-network-standard 5G cell, and the neighboring cell is a low-network-standard 4G cell. Therefore, under the condition that the signal quality of the current service cell is good, the equipment is ensured to reside in the high-network-standard 5G cell without reselecting the high-priority adjacent 4G cell.

Optionally, if the duration of the signal quality of the neighboring cell being higher than or equal to the cell reselection threshold satisfies the cell reselection timer value, the neighboring cell satisfies the cell reselection condition.

According to a first aspect, in a first implementation form, the method further comprises: and when the signal quality of the current serving cell is lower than a first threshold, starting measurement of the signal quality of the adjacent cell and starting a timer to time the time length that the signal quality of the adjacent cell is higher than or equal to a cell reselection threshold.

According to a first aspect, in a first implementation form, the method further comprises: and when the signal quality of the current serving cell is higher than or equal to the first threshold, preventing the starting of the measurement of the signal quality of the adjacent cell. Based on this, when camping on the present serving cell, the measurement is reduced under the condition that the signal quality of the present serving cell is good, so that the power consumption of the device can be reduced.

Optionally, the first threshold is higher than the preset threshold. Therefore, before the signal quality of the serving cell is reduced to the preset threshold, the UE starts the measurement of the signal quality of the adjacent cell in advance and records the time length that the signal quality of the adjacent cell meets the cell reselection threshold, so that the adjacent cell can be quickly reselected when the signal quality of the current serving cell is reduced to the preset threshold.

According to the first aspect, in a first implementation manner, optionally, the preset threshold and the first threshold are configured by a system, and the UE determines the preset threshold and the first threshold from received system broadcast information.

According to the first aspect, in a first implementation manner, optionally, the preset threshold and the first threshold are preconfigured in the UE.

According to the first aspect, in a second implementation manner, the cell reselection method further includes: and when the UE receives system information indicating the reselection priority of the current serving cell and the reselection priority of the adjacent cell, starting measurement of the signal quality of the adjacent cell and starting a timer to time the time length that the signal quality of the adjacent cell is higher than or equal to a cell reselection threshold. Generally, a UE receives such system information upon entering a current serving cell. Therefore, the UE starts measurement of the signal quality of the neighboring cell in advance, so as to evaluate the duration that the signal quality of the neighboring cell meets the cell reselection threshold in advance, so that the neighboring cell meeting the cell reselection condition can be reselected quickly when the signal quality of the current serving cell falls below the preset threshold.

According to the first aspect, in the first or second implementation manner, optionally, the neighboring cells are a plurality of neighboring cells, and the method further includes: and sequencing the adjacent cells according to the measurement results of the signal quality of the adjacent cells, and initiating cell reselection to the highest-sequencing adjacent cell meeting the cell reselection condition.

According to the first aspect, in a second implementation form, if a timed length of time that the signal quality of the neighboring cell is higher than or equal to a cell reselection threshold satisfies a cell reselection timer value, the neighboring cell satisfies a cell reselection condition.

According to the first aspect, in the first or second implementation manner, optionally, the values of the cell reselection threshold and the cell reselection timer value are configured by a system, and the UE determines the cell reselection threshold and the cell reselection timer value from received system broadcast information.

According to the first aspect, in the first or second implementation form, optionally, the cell reselection threshold and the cell reselection timer value are preconfigured in the UE.

According to the first aspect, in the first or second implementation manner, optionally, the preset threshold is adjusted by the UE.

According to the first aspect, in the first or second implementation manner, optionally, the preset threshold is adjusted by the UE according to a frequency of the current serving cell and/or an attenuation condition of the signal quality of the current serving cell.

According to the first aspect, in the first or second implementation manner, optionally, the UE increases the preset threshold when the frequency of the current serving cell is higher or the signal quality of the current serving cell is attenuated faster, and otherwise decreases the preset threshold. Therefore, under the condition of fast signal quality attenuation, the preset threshold is increased to avoid network loss of the UE; in the case of slow signal attenuation, the power consumption of the device can be reduced by lowering the preset threshold.

According to the first aspect, in the first or second implementation manner, optionally, the UE determines the reselection priority of the current serving cell and the reselection priority of the neighboring cell from the received system broadcast message.

According to the first aspect, in the first or second implementation, optionally, the UE determines the reselection priority of the current serving cell and the reselection priority of the neighboring cell from the received dedicated signaling.

According to the first aspect, in the first or second implementation manner, optionally, the parameter of the signal quality is one of RSRP, RSRQ, SINR, or any combination thereof.

According to a second aspect of the application, there is provided a user equipment comprising a memory for storing instructions and a processor configured to perform any of the above methods when executing the instructions.

According to a third aspect of the present application, there is provided a computer-readable storage medium having stored therein program code which, when executed by a computer or processor, implements any of the aforementioned methods.

According to a fourth aspect of the present application, a computer program product is provided, comprising program code which, when executed by a computer or processor, implements any of the aforementioned methods.

According to a fifth aspect of the present application, there is provided a communication apparatus comprising a reselection determination module, wherein, for a neighboring cell having a reselection priority higher than that of a current serving cell, the reselection determination module is configured to: when the signal quality of the current serving cell is higher than or equal to a preset threshold, preventing the cell of the adjacent cell from reselecting and residing in the current serving cell; and when the signal quality of the current serving cell is lower than the preset threshold and the adjacent cell meets the cell reselection condition, initiating cell reselection to the adjacent cell.

According to a fifth aspect of the present application, in a first implementation, the communication device further comprises a measurement control module configured to: and when the signal quality of the current serving cell is higher than or equal to the first threshold, preventing the starting of the measurement of the signal quality of the adjacent cell.

According to a fifth aspect of the present application, in a first implementation, the measurement control module is configured to: and when the signal quality of the current serving cell is lower than a first threshold, starting measurement of the signal quality of the adjacent cell and starting a timer to time the time length that the signal quality of the adjacent cell is higher than or equal to a cell reselection threshold.

According to a fifth aspect of the present application, in a second implementation, the measurement control module is configured to: when the UE receives system information indicating the reselection priority of the current serving cell and the reselection priority of the adjacent cell, starting measurement of the signal quality of the adjacent cell and starting a timer to time the time length that the signal quality of the adjacent cell is higher than or equal to a cell reselection threshold.

According to a fifth aspect of the present application, in the first or second implementation form, the neighboring cells are a plurality of neighboring cells, and the reselection determination module is configured to: ranking the plurality of neighboring cells according to the measurement results of the signal quality of the plurality of neighboring cells, and initiating cell reselection to a highest-ranked neighboring cell satisfying a cell reselection condition.

In the embodiment of the present application, when the serving cell signal quality meets a specific condition, for example, is higher than or equal to the preset threshold, the UE guarantees that the user camps on the current serving cell and prevents the cell from reselecting to a neighboring cell with high priority. In this way, the UE is not always prioritized to select the high reselection priority cell, which may affect the user experience.

Drawings

Fig. 1 is a schematic view of a cell reselection process according to an embodiment of the present disclosure;

fig. 2 is a flowchart of a cell reselection process provided in an embodiment of the present application;

fig. 3 is an implementation of a cell reselection process provided in an embodiment of the present application;

fig. 4 is another implementation manner of a cell reselection procedure provided in this embodiment.

Fig. 5 is a schematic diagram of a terminal device that executes a cell reselection process according to an embodiment of the present application.

Fig. 6 is a schematic diagram of a communication apparatus for performing a cell reselection procedure according to an embodiment of the present application.

Detailed Description

The technical solution provided by the present application is further explained below with reference to the drawings and the embodiments. It should be understood that the system or application scenario provided in the embodiments of the present application is mainly for explaining some possible implementations of the technical solutions of the present application, and should not be interpreted as a unique limitation of the technical solutions of the present application. As can be appreciated by those skilled in the art, as the system evolves and newer application scenarios arise, the technical solutions provided in the present application may still be applicable to the same or similar technical problems.

The terms "first," "second," and "third," etc. in the embodiments and drawings of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. Furthermore, the terms "comprises" and "comprising," as well as any variations thereof, are intended to refer to a non-exclusive inclusion, such as a list of steps or elements. A method, system, article, or apparatus is not necessarily limited to only those steps or elements that are literally set forth, but may include other steps or elements not expressly set forth or inherent to such process, system, article, or apparatus.

It is to be understood that, in the present application, "at least one" means one or more, "a plurality" means two or more. "and/or" for describing an association relationship of associated objects, indicating that there may be three relationships, e.g., "a and/or B" may indicate: only A, only B and both A and B are present, wherein A and B may be singular or plural. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single item(s) or plural items(s).

It should be understood that, in the present application, the sequence numbers of the steps in the respective methods do not mean the execution sequence, and the execution sequence of the steps in the respective processes or methods should be determined by the functions and the inherent logic thereof, and should not constitute any limitation to the implementation process of the embodiments of the present application.

The following description is directed to technical terms in the communication systems to which the present application relates.

The present application relates generally to communication systems and devices providing wireless network services and devices using wireless network services.

The devices providing wireless network services refer to devices forming a wireless communication network, and may be referred to as network devices (network elements) for short. Network devices are typically assigned to and operated or maintained by operators (e.g., china mobile and Vodafone) or infrastructure providers (e.g., tower companies). The network devices may be further classified into Radio Access Network (RAN) devices and Core Network (CN) devices. A typical RAN equipment includes a Base Station (BS).

It should be understood that a base station may also sometimes be referred to as a wireless Access Point (AP), or a Transmission Reception Point (TRP). Specifically, the base station may be a general Node B (gNB) in a 5G New Radio (NR) system, or an evolved Node B (eNB) in a 4G Long Term Evolution (LTE) system. The base station may be classified as a macro base station (macro base station) or a micro base station (micro base station) according to a physical form or a transmission power of the base station. A micro base station is sometimes also referred to as a small base station or small cell (small cell).

Devices using wireless network services are often located at the edge of the network and may be referred to simply as terminal (terminating) devices. The terminal equipment can establish connection with the network equipment and provide specific wireless communication services for users based on the services of the network equipment. It should be appreciated that terminal equipment is sometimes referred to as User Equipment (UE), or Subscriber Unit (SU), because of its tighter relationship to the user. Furthermore, the terminal equipment tends to move with the user, sometimes referred to as a Mobile Station (MS), relative to the base station, which is typically located at a fixed location. Some network devices, such as Relay Nodes (RNs) or wireless routers, may also be considered as terminals due to their UE identities or due to their affiliations with users.

Specifically, the terminal device may be a mobile phone (mobile phone), a tablet computer (tablet computer), a laptop computer (laptop computer), a wearable device (such as a smart watch, a smart bracelet, a smart helmet, smart glasses), and other devices with wireless access capability, such as a smart car, various internet of things (IOT) devices, including various smart home devices (such as a smart meter and a smart home appliance), and smart city devices (such as a security protection or monitoring device, a smart road transportation facility), and the like.

The network type refers to a network type, such as lte (long term evolution) (4G), nr (new Radio) (5G), geran (gsm EDGE Radio Access network) (2G), wcdma (wideband Code Division Multiple Access) (3G), and utran (umts Terrestrial Radio Access network) (3G).

In the present application, the "high network standard" is relatively speaking, for example, the network standard of 5G may be higher than that of 4G, and the network standard of 4G may be higher than that of 3G or 2G. For example, LTE belongs to 4G, NR belongs to 5G, and thus the network system of NR is higher than that of LTE. With the development of communication technology, there may be a 6G network, and the network standard of the 6G network is higher than that of the NR under 5G.

The serving cell refers to a cell in which the UE currently resides or a cell in which data transmission is being provided for the UE.

Cell reselection, which refers to a process in which a UE, while camped on a current serving cell, measures and evaluates signal qualities of the current serving cell and neighboring cells to find a neighboring cell that is superior to the current serving cell and selects the neighboring cell to provide service.

"Inter-system (Inter-RAT) cell reselection" refers to cell reselection between cells of different types of radio access networks. For example, the serving cell and the neighboring cell have different network systems, and different network systems usually employ different Radio Access Technologies (RATs), so the serving cell and the neighboring cell belong to different RAT systems. Cell reselection to such a serving cell to a neighboring cell is therefore considered as "Inter-system (Inter-RAT) cell reselection". A cell reselection from a serving cell to a neighboring cell is a "pilot cell reselection" if the serving cell and the neighboring cell are different frequency points of the same radio access network.

The present application is directed to a case of a heterogeneous cell reselection, a heterogeneous system (Inter-RAT) cell reselection, or a heterogeneous cell reselection by a terminal device, e.g., a UE, from a serving cell with a low reselection priority to a neighboring cell with a high reselection priority. The embodiment of the application describes a scenario that the reselection priority of the high-system network is lower than that of the low-system network, namely, cell reselection from a serving cell with the high-system low reselection priority to an adjacent cell with the low-system high reselection priority is performed.

The embodiment of the present application specifically describes a cell reselection process by taking cell reselection from a 5G high-network-system NR serving cell with a low reselection priority to a 4G low-network-system EUTRA neighboring cell with a high reselection priority as an example. The cell reselection process between other network systems is also applicable, for example, the cell reselection from the serving cell of the 4G network system with low reselection priority to the cell of the low network system with high reselection priority, such as 2G, 3G, etc., is also applicable.

For convenience of description, in the embodiments of the present application, a base station BS and a user equipment UE are taken as examples, and a technical solution of the embodiments of the present application is described in detail.

Fig. 1 is a schematic view of a cell reselection process provided in an embodiment of the present application.

As shown in fig. 1, the UE currently resides in the serving Cell 1. For example, as the UE moves, the signal quality deteriorates, and the current serving Cell1 may not be the optimal Cell. The UE may measure the signal quality of the current serving Cell1 and the neighboring Cell2, in particular the high reselection priority neighboring Cell2, in the idle state to determine whether to reselect to such neighboring Cell 2. The UE, when idle, takes a measurement preferentially on a Cell, for example Cell2, of higher reselection priority than the serving Cell1 to evaluate whether such a neighboring Cell2 is reselected with a higher reselection priority than the serving Cell.

Here, the high-priority neighbor cell may be a heterogeneous cell or a heterogeneous cell compared to the current serving cell, or a heterogeneous frequency cell. For example, the high priority neighbor cell is a low network format 4G, e.g., EUTRA, and the low priority current serving cell is a high network format 5G, e.g., NR.

For ease of illustration, fig. 1 shows only one neighboring Cell 2. This is merely exemplary. There may be several such high reselection priority neighboring cells Cell 2.

The base station BS1 may broadcast system information periodically in its serving Cell 1. The UE receives the system information in the serving Cell1, which indicates the reselection priority corresponding to the current serving Cell1 and the reselection priority corresponding to the neighboring Cell 2.

Generally, a serving cell and each neighboring cell correspond to a specific RAT and a corresponding frequency point based on respective network systems. For example, the current serving cell is of high network type 5G, the corresponding RAT is NR, the neighboring cell is of low network type 4G, and the corresponding RAT is EUTRA.

Before the UE selects the serving Cell1, the UE may also be configured with the RAT corresponding to the neighboring Cell2, for example, the frequency point information of EUTRA and the corresponding reselection priority in advance. Therefore, the UE can know the reselection priority corresponding to the neighboring Cell 2. Other manners may also be adopted to obtain the reselection priority corresponding to the current serving Cell1 and the reselection priority corresponding to the neighboring Cell 2. For example, the UE receives dedicated signaling, for example, RRC signaling, to know the reselection priority level corresponding to the serving Cell1 and the reselection priority level corresponding to the neighboring Cell 2. The manner in which the UE obtains information of the reselection priority is not limited to the above manner.

The UE can know the neighboring Cell2 with higher reselection priority than the current serving Cell1 through the received or preconfigured reselection priority information.

The Cell reselection method provided in the embodiment of the present application is directed to the evaluation of Cell reselection of the neighboring Cell2 whose reselection priority is higher than that of the current serving Cell 1.

In the cell reselection method according to the embodiment of the present application, for an adjacent cell whose reselection priority is higher than that of the current serving cell, the method includes: when the signal quality of the current serving cell is higher than or equal to a preset threshold, preventing the cell of the adjacent cell from reselecting and residing in the current serving cell; and when the signal quality of the current serving cell is lower than the preset threshold and the adjacent cell meets the cell reselection condition, initiating cell reselection to the adjacent cell.

Fig. 2 is a flowchart of a cell reselection procedure performed by a UE according to an embodiment of the present disclosure. As shown in step S10, the UE camps on the current serving cell. Next, as shown in step S12, for a neighboring cell whose reselection priority is higher than that of the current serving cell, the UE determines whether the neighboring cell satisfies the cell reselection condition. If the neighboring cell satisfies the cell reselection condition, the UE determines whether the signal quality of the current serving cell is lower than a preset threshold as shown in step S13. If the signal quality of the current service cell is lower than a preset threshold, the UE initiates cell reselection to the adjacent cell; if the signal quality of the current serving cell is not lower than the preset threshold, i.e. higher than or equal to the preset threshold, the UE continues to camp on the current serving cell and prevents cell reselection to the neighboring cell.

The cell reselection condition may be that the signal quality of the neighboring cell is higher than or equal to a cell reselection threshold, and a counted time length of the signal quality of the neighboring cell being higher than or equal to the cell reselection threshold satisfies a cell reselection timer value, for example. This is exemplary only and not limiting. Other cell reselection conditions may also be employed.

The order of the above steps S12 and S13 is exemplary. For example, step S13 may be performed first, that is, it is determined whether the signal quality of the current serving cell is lower than a preset threshold. If not, namely the signal quality of the current serving cell is higher than or equal to the preset threshold, the UE continues to reside in the current serving cell and prevents cell reselection to the adjacent cell. If the signal quality of the current serving cell is lower than the preset threshold, step S12 is executed, and the UE determines whether the neighboring cell meets the cell reselection condition, and if so, initiates cell reselection to the neighboring cell.

A specific implementation of the cell reselection procedure provided in the embodiment of the present application is described in detail below with reference to a specific scenario of fig. 3.

The present implementation takes as an example cell reselection in which the current serving cell is an NR cell of a low-priority 5G system and the neighboring cell is an EUTRA cell of a high-priority 4G system.

Specifically, the UE is camped on the current serving NR cell and receives system broadcast information, such as system information blocks SIB2 and SIB5, from the base station gsnodeb, which carries information that can be seen in 3GPP TS 38.304. Specifically, the SIB2 carries cell reselection parameters corresponding to the current serving cell, such as a cellreselection priority and a cellreselection priority (optional) cell, frequency point information indicating an NR scheme corresponding to the current serving cell and corresponding cell reselection priority information, so that the UE knows the reselection priority corresponding to the current serving NR cell by receiving the SIB 2. The SIB5 carries cell reselection parameters corresponding to the neighboring cells, such as cellreselection priority and cellreselection priority (optional) cells, and indicates frequency point information of an EUTRA system corresponding to the neighboring cells and corresponding reselection priority information, so that the UE obtains the reselection priority information corresponding to the neighboring EUTRA cell by receiving the SIB 5. The embodiments of the present application are not limited thereto.

The UE may determine the high priority neighboring EUTRA cell by receiving the above cell reselection parameter, e.g., cellreselection priority. If the two cells, that is, the cell reselection priorities corresponding to the frequency points of the current serving NR cell and the neighboring EUTRA cell, are different, the reselection priorities of the two cells can be compared through the cell reselection priorities of the two cells. If both have the same cellreselection priority and have cellreselection priority cells, the reselection priorities of both can be compared. Further details of the above information of reselection priorities can be found in 3GPP TS 38.304 protocol specifications. The embodiments of the present application are not limited thereto.

The UE may measure the signal quality of the current serving NR cell and the neighboring EUTRA cell to evaluate whether a cell reselection is to the neighboring EUTRA cell. The parameter of the Signal Quality may be one of RSRP (Reference Signal Received Power), RSRQ (Reference Signal Received Quality), SINR (Signal to Interference plus Noise Ratio), or any combination thereof. The specific way in which the UE measures the signal quality of the current serving NR cell and the neighboring EUTRA cells is well known to those skilled in the art and will not be described here.

In this implementation, as shown in step S21, the UE prevents the initiation of measurements on the EUTRA cell in case the signal quality of the current serving NR cell is good, e.g. above a first threshold. This may reduce the power consumption of the UE by reducing the measurements. Preferably, the first threshold is higher than the preset threshold, so that, in practice, in case the signal quality of the current serving cell gradually decreases as the UE moves, the UE starts measurement of the EUTRA cell in advance before the signal quality falls to the preset threshold.

As shown in step S22, when the signal quality of the current serving NR cell is below a first threshold, measurement of the signal quality of the EUTRA cell is initiated. Preferably, in initiating the measurement, a timer is started to time a duration that the signal quality of the EUTRA cell is higher than or equal to a cell reselection threshold. The cell reselection threshold may be referred to as 3GPP TS 38.304, and is sent to the UE in SIB5, for example. Here, the value of the first threshold may be configured by the system, and is broadcast to the UE in system information. Of course, the cell reselection threshold and the first threshold may also be pre-configured in the UE. Further, in step S22, a buffer value may be set, i.e., measurement of the signal quality of the neighboring EUTRA cell may be initiated when the signal quality of the current serving NR cell falls below the buffer value smaller than the first threshold.

Further, as shown in step S23, when the signal quality of the current serving NR cell is higher than or equal to the preset threshold, the UE continues to camp on the current serving NR cell while preventing cell reselection to the EUTRA cell. In this way, in case the signal quality of the current serving NR cell is good, it is guaranteed to camp on the current serving NR cell without reselecting to the EUTRA cell of the high reselection priority. It is to be appreciated that, at this time, even in the case where it is determined that the time duration in which the signal quality of the neighboring EUTRA cell is higher than or equal to the cell reselection threshold satisfies the cell reselection timer value, if the signal quality of the current serving cell is higher than or equal to the preset threshold, the neighboring EUTRA cell with the high reselection priority is prevented from being reselected to by the cell while camping on the current serving NR cell, as shown in step S23.

Here, the preset threshold may be configured by the system, for example, the system information broadcast by the base station gsnodeb in the current serving NR cell includes a value of the preset threshold. The UE determines the preset threshold from the received system information for use in the cell reselection method. The system may add information indicating the preset threshold to an existing system information block or separately define a system information block to indicate the value of the preset threshold, which is broadcast to the UE in the current serving NR cell.

The present embodiment is not limited thereto. The preset threshold may also be pre-configured in the UE.

Further, as shown in step S24, when the signal quality of the current serving NR cell is lower than the preset threshold, if the neighboring EUTRA cell satisfies the cell reselection condition, for example, the neighboring EUTRA cell has a signal quality higher than or equal to the cell reselection threshold and a time period when the signal quality of the neighboring cell is higher than or equal to the cell reselection threshold satisfies the cell reselection timer value, a cell reselection is initiated to the neighboring EUTRA cell.

Here, the cell reselection timer value may be, for example, see T defined in 3GPP TS 38.304_{reselectionRAT}It is sent to the UE, for example, in SIB 5. Different cell reselection timer values (T) may be defined for different RAT technologies_{reselectionRAT}). The cell reselection timer value may be configured by the system, which is well known to those skilled in the art and will not be described in detail.

It will be appreciated that in an actual scenario there may be more than one neighbouring EUTRA cell having a higher reselection priority than the high reselection priority of the current serving NR cell.

The UE may measure the signal quality of these high priority neighboring EUTRA cells and then rank the signal quality of these high priority neighboring EUTRA cells according to the measurement results. And when the signal quality of the current service NR cell is reduced to be lower than a preset threshold, the UE initiates cell reselection to an adjacent EUTRA cell which meets the cell reselection condition and has the highest signal quality ranking.

In this implementation, the first threshold is greater than a preset threshold. When the signal quality of the serving cell falls below a first threshold, which is not yet a preset threshold, the UE starts measurement of the signal quality of the neighboring EUTRA cell in advance and records the duration for which the signal quality of the neighboring EUTRA cell meets the cell reselection threshold. In this way, a neighboring EUTRA cell meeting the reselection condition can be reselected quickly when the signal quality of the current serving NR cell falls below a preset threshold.

In this implementation, the advantage of such a setting that the first threshold is greater than the preset threshold is that: when the NR cell is not attenuated to the preset threshold, the measurement of the signal quality of the adjacent cell is started in advance, and the adjacent cell meeting the reselection condition is determined, so that the adjacent cell can be reselected quickly when the signal quality of the NR cell is attenuated to the preset threshold, and the network loss of the UE is avoided.

In this implementation manner, the preset threshold may be a fixed value, that is, a fixed value that the UE can set, or a value that is dynamically adjusted. The preset threshold may be adjusted by the UE. The UE adjusts according to the frequency of the current serving NR cell and/or the attenuation of the signal quality of the current serving NR cell. Preferably, the UE increases the preset threshold when the frequency of the current serving cell is higher or the signal quality attenuation of the current serving cell is faster, and decreases the preset threshold otherwise. Therefore, under the condition of fast signal quality attenuation, the preset threshold is increased to avoid network loss of the UE; in the case of slow signal attenuation, the power consumption of the device can be reduced by lowering the preset threshold.

In a practical scenario, in view of network deployment of an operator, there may be many cases in a network configuration where a reselection priority of a 5G cell is the same as a reselection priority of a 4G cell, or even lower than the reselection priority of the 4G cell, that is, a reselection priority of a high-network-standard (e.g., 5G) cell is lower than a reselection priority of a low-network-standard (e.g., 4G, etc.) cell. In this case, based on the cell reselection implemented by the above method, the current serving cell is a high-network-type 5G cell with a low priority and the neighboring cell is a low-network-type 4G cell with a high priority, and the method can ensure that the UE resides in the current serving cell with the high-network-type 5G under the condition that the signal quality of the current serving cell with the high-network-type 5G is good, thereby improving the user experience. Further, the first threshold for starting to measure the signal quality of the adjacent cell is increased, for example, higher than the preset threshold, so that the UE evaluates the signal quality of the adjacent cell in advance to meet the cell reselection threshold, and in a scenario where the signal quality of the serving cell is degraded, the UE can quickly initiate cell reselection of a new cell to avoid UE network loss.

Another specific implementation of the cell reselection procedure provided in the embodiment of the present application is described in detail below with reference to the flowchart of fig. 4.

The present implementation still takes as an example cell reselection from a current serving NR cell of low priority 5G system to an adjacent EUTRA cell of high priority 4G system.

The difference from the cell reselection procedure of fig. 3 is that in this implementation, as shown in step S31, measurement of the signal quality of the EUTRA cell is immediately initiated upon determining that the EUTRA cell reselection priority is higher than the reselection priority of the current serving NR cell.

In particular, the UE initiates measurement of signal quality of a neighboring EUTRA cell indicating a high reselection priority upon receiving system information of the neighboring EUTRA cell.

Similar to fig. 3, the UE is camped on the current serving NR cell and receives system broadcast information, such as system information blocks SIB2 and SIB5, from the base station gsnodeb, which carry information referred to the description above in relation to fig. 3. And will not be described in detail herein.

Thus, as shown in step S31, measurement of the signal quality of the neighboring EUTRA cell is initiated when the UE receives system information (e.g., system information blocks SIB2 and SIB5) indicating the reselection priority of the current serving NR cell and the reselection priority of the neighboring EUTRA cell. Optionally, when the measurement of the signal quality of the EUTRA cell is started, a timer is started to time a period of time during which the signal quality of the neighboring EUTRA cell is higher than or equal to a cell reselection threshold. Here, the cell reselection threshold is transmitted to the UE, for example, by being included in SIB 5.

When the signal quality of the current serving NR cell is higher than or equal to the preset threshold, the UE continues to camp on the current serving NR cell while preventing cell reselection to the EUTRA cell, as shown in step S32.

When the signal quality of the current serving NR cell is lower than the preset threshold and the neighboring EUTRA cell satisfies the cell reselection condition, for example, a time period during which the signal quality is higher than or equal to the cell reselection threshold satisfies (i.e., reaches) a cell reselection timer value (T) as shown in step S33_{reselectionRAT}) And initiating cell reselection to the neighboring EUTRA cell.

In this implementation, in general, the UE receives system information, including SIB2 and SIB5 described above, while camped on the current serving NR cell. Through the received system information, the UE learns that the reselection priority is higher than that of the adjacent EUTRAN cell of the current service NR cell, and then starts the measurement of the signal quality of the adjacent EUTRAN cell, so that the time length for the signal quality of the adjacent EUTRAN cell to meet the cell reselection threshold can be evaluated in advance, and the EUTRAN cell can be rapidly reselected when the signal quality of the current service NR cell is reduced to be lower than the preset threshold.

The cell reselection method provided by the embodiment of the invention can avoid various problems caused by unreasonable cell reselection priorities configured by a system under the condition of not changing the cell reselection priorities and the cell reselection timer values configured by the system. The method can enable the UE to reside in the current service cell as much as possible without reselecting to a high-priority adjacent cell under the condition that the signal of the current service cell is good enough. When the current service cell is degraded, the cell reselection can be quickly executed, the network loss of the UE is avoided, and the method is particularly suitable for the scene of 5G network signal fast attenuation.

The methods of embodiments of the present application may include various other operations and/or variations of the operations shown. Likewise, the order of the steps of the flow diagrams may be modified. It should be understood that not all steps in the flow chart are to be performed.

In the above-described embodiments of the present application, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer program codes or computer program instructions. The procedures or functions described in accordance with the embodiments of the present application are generated in whole or in part when the program code or computer program instructions are loaded and executed on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device.

Fig. 5 is a schematic diagram of a terminal device that performs the cell reselection process according to an embodiment of the present application.

As shown in fig. 5, a terminal device, such as User Equipment (UE)100, includes a processor 101, a memory 102, and a transceiver 103. The processor 101 is used to implement processing of communication protocols and communication data by executing computer-readable and executable instructions (or code), such as program modules, and the like.

The memory 102 is used to store computer-readable and executable instructions (or code) and data, such as program modules. The transceiver 103 is used for reception and transmission of data. For ease of illustration, only the memory 102 and the processor 101 and transceiver 103 are shown in fig. 5. In addition to the above components, the UE may also include other various types of components or components that perform various functions, and other components are not listed here to avoid obscuring the technical solution proposed by the present invention.

The methods of embodiments of the present application may be implemented by the processor 101 executing computer readable and executable instructions (or code). Computer-readable and executable instructions (or code), such as program modules, may reside in the memory 102. By way of example, memory 102 may include non-transitory computer storage media.

Specifically, in performing the method of embodiments of the present application, for example, the transceiver 103 receives data from a base station and transmits the data to the processor 101. Data here includes, but is not limited to, the system information described above, such as SIB2 and SIB 5. The data may also include other various types of information, as desired.

The processor 101, when executing computer readable and/or executable instructions (or code), implements the methods of the embodiments described above. If it is determined that cell reselection to a neighboring cell is to be initiated, the processor 101 sends control information to the transceiver 103, and the transceiver 103 in turn sends a cell reselection signaling to the base station of the neighboring cell to initiate cell reselection to the neighboring cell, as shown in steps S14, S24 or S33.

The present application also provides a computer program product comprising computer program code or computer program instructions which, when executed by a computer or processor, performs any of the methods of the embodiments of the present application.

The computer program code or computer program instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer program code or computer program instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (e.g., coaxial cable, optical fiber, etc.) or wirelessly (e.g., infrared, radio, microwave, etc.). The computer readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, or the like. Computer-readable media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules or other data. Computer-readable media include, but are not limited to: random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc ROM (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed to retrieve the information.

The communication apparatus 200 includes a measurement control module 201 and a reselection determination module 202.

In performing the method of the embodiment of the present application, for a neighboring cell having a higher reselection priority than the current serving cell, the reselection determination module 202 may be configured to: when the signal quality of the current serving cell is higher than or equal to a preset threshold, preventing the cell of the adjacent cell from reselecting and residing in the current serving cell; and when the signal quality of the current serving cell is lower than the preset threshold and the adjacent cell meets the cell reselection condition, initiating cell reselection to the adjacent cell.

In performing the method of the first implementation manner of the embodiment of the present application, the measurement control module 201 may be configured to: and when the signal quality of the current serving cell is higher than or equal to the first threshold, preventing the starting of the measurement of the signal quality of the adjacent cell.

In performing the method of the first implementation manner of the embodiment of the present application, the measurement control module 201 may be configured to: and when the signal quality of the current serving cell is lower than a first threshold, starting measurement of the signal quality of the adjacent cell and starting a timer to time the time length that the signal quality of the adjacent cell is higher than or equal to a cell reselection threshold.

In performing the method of the second implementation manner of the embodiment of the present application, the measurement control module 201 may be configured to: when the UE receives system information indicating the reselection priority of the current serving cell and the reselection priority of the adjacent cell, starting measurement of the signal quality of the adjacent cell and starting a timer to time the time length that the signal quality of the adjacent cell is higher than or equal to a cell reselection threshold.

In performing the method of the first or second implementation manner of the embodiment of the present application, where the neighboring cells are multiple neighboring cells, the reselection determination module 202 may be configured to: ranking the plurality of neighboring cells according to the measurement results of the signal quality of the plurality of neighboring cells, and initiating cell reselection to a highest-ranked neighboring cell satisfying a cell reselection condition.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive various changes or substitutions within the scope of the present disclosure, which should be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

A method of cell reselection, comprising: for a neighboring cell with a reselection priority higher than the reselection priority of the current serving cell, then: when the signal quality of the current serving cell is higher than or equal to a preset threshold, preventing the cell of the adjacent cell from reselecting and residing in the current serving cell; and when the signal quality of the current serving cell is lower than the preset threshold and the adjacent cell meets the cell reselection condition, initiating cell reselection to the adjacent cell.
The cell reselection method of claim 1, wherein the neighboring cell is a different-system cell or a same-system different-frequency cell compared to a current serving cell.
The cell reselection method of claim 1 or 2, wherein the current serving cell is a high-network-standard 5G cell, and the neighboring cell is a low-network-standard 4G cell.
The cell reselection method of any of claims 1-3, wherein the neighboring cell satisfies the cell reselection condition if a cell reselection timer value is satisfied for a time period in which the signal quality of the neighboring cell is greater than or equal to a cell reselection threshold.
The cell reselection method of any of claims 1-4, wherein the cell reselection method further comprises: and when the signal quality of the current serving cell is lower than a first threshold, starting measurement of the signal quality of the adjacent cell and starting a timer to time the time length that the signal quality of the adjacent cell is higher than or equal to a cell reselection threshold.
The cell reselection method of any of claims 1-5, wherein the method further comprises: and when the signal quality of the current serving cell is higher than or equal to the first threshold, preventing the starting of the measurement of the signal quality of the adjacent cell.
The cell reselection method of claim 5 or 6, wherein the first threshold is higher than the preset threshold.
The cell reselection method of claim 7, wherein the preset threshold and the first threshold are configured by a system, and the UE determines the preset threshold and the first threshold from received system broadcast information.
The cell reselection method of claim 7, wherein the preset threshold and the first threshold are preconfigured in the UE.
The cell reselection method of any of claims 1-4, wherein the cell reselection method further comprises: and when the UE receives system information indicating the reselection priority of the current serving cell and the reselection priority of the adjacent cell, starting measurement of the signal quality of the adjacent cell and starting a timer to time the time length that the signal quality of the adjacent cell is higher than or equal to a cell reselection threshold.
The cell reselection method of any of claims 1-10, wherein the neighboring cell is a plurality of neighboring cells, the method further comprising: and sequencing the adjacent cells according to the measurement results of the signal quality of the adjacent cells, and initiating cell reselection to the highest-sequencing adjacent cell meeting the cell reselection condition.
The cell reselection method of claim 4, wherein the cell reselection threshold and the cell reselection timer value are configured by a system, and the UE determines the cell reselection threshold and the cell reselection timer value from received system broadcast information.
The cell reselection method of claim 4, wherein the cell reselection threshold and the cell reselection timer value are preconfigured in the UE.
The cell reselection method of any of claims 1-13, wherein the preset threshold is adjusted by the UE.
The cell reselection method of claim 14, wherein the preset threshold is adjusted by the UE according to a frequency of the current serving cell and/or a fading condition of the signal quality of the current serving cell.
The cell reselection method of claim 15, wherein the UE increases the preset threshold when a frequency of the current serving cell is higher or a signal quality of the current serving cell is attenuated faster, and otherwise decreases the preset threshold.
The cell reselection method of any of claims 1-16, wherein the UE determines the reselection priority of the current serving cell and the reselection priority of the neighboring cell from the received system broadcast message.
The cell reselection method of any of claims 1-16, wherein the UE determines the reselection priority of the current serving cell and the reselection priority of the neighboring cell from the received dedicated signaling.
The cell reselection method of any of claims 1-18, wherein the parameter of signal quality is one of RSRP, RSRQ, SINR, or any combination.
A user equipment comprising a memory for storing instructions and a processor configured to perform any of the methods of any of claims 1-19 when the instructions are executed.
A computer-readable storage medium having program code stored therein, which when executed by a computer or processor implements any of the methods of claims 1-20.
A computer program product comprising program code which, when executed by a computer or processor, implements any of the methods of any of claims 1-21.
A communication device, comprising: a reselection determination module, wherein, for a neighboring cell having a reselection priority higher than that of the current serving cell, the reselection determination module is configured to: when the signal quality of the current serving cell is higher than or equal to a preset threshold, preventing the cell of the adjacent cell from reselecting and residing in the current serving cell; and when the signal quality of the current serving cell is lower than the preset threshold and the adjacent cell meets the cell reselection condition, initiating cell reselection to the adjacent cell.
The communications apparatus of claim 23, wherein the communications module further comprises a measurement control module configured to: and when the signal quality of the current serving cell is higher than or equal to the first threshold, preventing the starting of the measurement of the signal quality of the adjacent cell.
The communication device of claim 23 or 24, wherein the measurement control module is configured to: and when the signal quality of the current serving cell is lower than a first threshold, starting measurement of the signal quality of the adjacent cell and starting a timer to time the time length that the signal quality of the adjacent cell is higher than or equal to a cell reselection threshold.
The communications apparatus of claim 25, wherein the measurement control module is configured to: when the UE receives system information indicating the reselection priority of the current serving cell and the reselection priority of the adjacent cell, starting measurement of the signal quality of the adjacent cell and starting a timer to time the time length that the signal quality of the adjacent cell is higher than or equal to a cell reselection threshold.
The communication device of any one of claims 23-26, wherein the neighboring cell is a plurality of neighboring cells, the reselection determination module configured to: and sequencing the adjacent cells according to the measurement results of the signal quality of the adjacent cells, and initiating cell reselection to the highest-sequencing adjacent cell meeting the cell reselection condition.