CN112714481A

CN112714481A - BWP switching method and base station equipment

Info

Publication number: CN112714481A
Application number: CN202110327718.1A
Authority: CN
Inventors: 李振辉; 浦学东; 郭峰; 李文情
Original assignee: Hangzhou H3C Technologies Co Ltd
Current assignee: Hangzhou H3C Technologies Co Ltd; New H3C Technologies Co Ltd
Priority date: 2021-03-26
Filing date: 2021-03-26
Publication date: 2021-04-27
Anticipated expiration: 2041-03-26
Also published as: CN112714481B

Abstract

The present specification provides a BWP handover method and a base station apparatus, the method including: informing a user to perform BWP switching, determining whether the user completes BWP switching according to the fact that the error rate in a preset uplink and downlink continuous scheduling frequency reaches a preset value, and if the BWP switching is not completed, increasing the DCI repetition frequency of the user and indicating the user to perform BWP switching again; or terminating the user BWP handover. By the method, the verification after the BWP switching of the user can be realized, whether the BWP activation states of the UE and the base station are consistent or not is confirmed, and packet loss which can be as long as several seconds and even UE call drop are avoided.

Description

BWP switching method and base station equipment

Technical Field

The present disclosure relates to the field of wireless communications, and in particular, to a BWP handover method and a base station device.

Background

BWP (Bandwidth Part, partial Bandwidth) is a subset of the total Bandwidth of a cell. We sometimes refer to this technique by ba (bandwidth adaptation), that is, flexibly adjusting the size of the receiving and transmitting bandwidths of the UE by bandwidth adaptive change, so that the receiving and transmitting bandwidths of the UE do not need to be as large as the bandwidth of the cell.

In NR (New Radio), the bandwidth of the UE may be dynamically changed. As shown in fig. 1, at the first moment, the traffic of the UE is large, and the system configures a large bandwidth (BWP 1) for the UE, where the corresponding bandwidth is 40MHz, and each subcarrier occupies 15 KHz; at the second moment, when the system senses that the traffic of the UE is reduced, a small bandwidth (BWP 2) is configured for the UE, the bandwidth is 10MHz, each subcarrier occupies 15KHz, and the basic communication requirement is met, and the UE uses a lower bandwidth in the period, so that the consumed power is reduced; at the third moment, when the system finds that there is wide frequency selective fading in the bandwidth of BWP1, or there is a shortage of resources in the frequency range of BWP1, or the terminal needs to perform a specific type of service and needs a special sub-carrier bandwidth, then a new bandwidth (BWP 3) is configured for the UE, where the bandwidth is 20MHz and each sub-carrier occupies 60 KHz.

BWP, while providing much flexibility to 5G, reducing power consumption, etc., also complicates the design of 5G systems.

Disclosure of Invention

The present disclosure provides a BWP handover method and a base station apparatus, by which it is possible to determine whether a user has completed BWP handover, and to verify whether the user is consistent with a BWP state activated by a base station.

The present disclosure provides a BWP handover method, including:

informing a user to perform BWP switching;

determining whether the user completes BWP switching or not according to the fact that the error rate in the preset uplink and downlink continuous scheduling times reaches a preset value;

if the BWP switching is not finished, increasing the DCI repetition times of the user and indicating the user to perform the BWP switching again; or terminating the user BWP handover.

Optionally, when it is detected that the state attribute of the user reaches the preset condition, the user is notified to perform BWP switching.

Optionally, the notifying the user of the BWP handover specifically includes:

and sending a notification carrying the Downlink Control Information (DCI) repetition times to the user so that the user can perform BWP switching according to the DCI repetition times.

Optionally, the increasing the number of DCI repetitions of the user and instructing the user to perform BWP handover again specifically includes:

and on the basis of the repetition times of the original configured DCI, increasing the repetition times of the DCI and informing the user so that the user performs BWP switching again according to the newly increased repetition times of the DCI.

Optionally, if it is determined that the user does not complete BWP handover, the PDCCH aggregation level of the user is increased.

Optionally, terminating the BWP handover of the user specifically includes: a BWP prohibit switch timer is set such that if the BWP switch times out, the BWP prohibit switch is executed.

It can be seen from the foregoing embodiments that, by determining whether the user completes BWP handover (i.e., verification after user handover) according to that the error rate within the preset uplink and downlink consecutive scheduling times reaches the preset value, and selecting to increase DCI repetition times to perform handover or terminate handover when determining that BWP handover is not completed, packet loss up to several seconds, even UE call drop, due to inconsistency between the user and the BWP state of the base station is avoided.

The present disclosure also provides a base station device, including:

a notification module for notifying a user of BWP switching;

the judging module is used for determining whether the user completes BWP switching or not according to the fact that the error rate in the preset uplink and downlink continuous scheduling times reaches a preset value;

a processing module, configured to determine that BWP handover is not completed, increase DCI repetition times of the user and instruct the user to perform BWP handover again; or terminating the user BWP handover.

Optionally, the processing module is further configured to increase a PDCCH aggregation level of the user when the base station device determines that the user does not complete BWP handover.

Optionally, the processing module is specifically configured to increase the DCI repetition times based on the original configured DCI repetition times, and notify the user, so that the user performs BWP switching again according to the newly increased DCI repetition times.

Optionally, the processing module is further configured to set a BWP prohibit switching timer, so that if the BWP switching is overtime, the BWP prohibit switching is executed.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present specification and together with the description, serve to explain the principles of the specification.

Fig. 1 is a schematic diagram of a spectrum distribution according to an embodiment of the disclosure.

Fig. 2 is a flowchart illustrating a BWP switching method according to an embodiment of the present disclosure.

Fig. 3 is a logic diagram illustrating a BWP switching method according to an embodiment of the present disclosure.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present specification. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the specification, as detailed in the appended claims.

The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the description. As used in this specification and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It should be understood that although the terms first, second, third, etc. may be used herein to describe various information, these information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, the first information may also be referred to as second information, and similarly, the second information may also be referred to as first information, without departing from the scope of the present specification. The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination", depending on the context.

The technical advantages of BWP are mainly the following:

the UE does not need to support all bandwidths, only needs to meet the requirement of the lowest bandwidth, is beneficial to the development of low-cost terminals and promotes the development of the industry;

the UE monitors or transmits the control channel with low power consumption in a low service period, and receives or transmits with large bandwidth in a high service period, so that the power consumption can be obviously reduced;

adapting different numerology (parameter set) according to different service models carried by the network;

discontinuous frequency bands can be configured in the carrier, which is more beneficial to the efficient utilization of the frequency spectrum of an operator;

according to the quality of different frequency domain channels, the UE works on a better frequency domain channel by switching between different BWPs, thereby improving the utilization efficiency of air interface resources.

In the NR FDD system, one UE can configure 4 DL BWPs and 4 UL BWPs at most. In the NR TDD system, one UE configures 4 BWP pairs at maximum. BWP Pair means that DL BWP ID is the same as UL BWP ID, and the center frequency points of DL BWP and UL BWP are the same, but the bandwidth, subcarrier spacing and CP type may not be the same. However, it should be noted that the bandwidth of BWP must be equal to or greater than SSB, but BWP does not necessarily include SSB. For the same UE, only one BWP can be activated in DL or UL at the same time, and the UE performs data transceiving and PDCCH retrieval on the BWP. When BWP handover is performed, uplink and downlink BWP needs to be handed over simultaneously.

For DCI based BWP handover, the current 3GPP R15 protocol does not describe or specify the reliability of successful BWP handover and the processing of misalignment of BWP states belonging to UE and base station during handover. In a complex environment of a laboratory and an external field, aiming at a multi-BWP switching test, the state of the BWP where UE and a base station with a certain probability (the specific probability is related to the interference environment at that time) are not aligned, once the BWP state is not aligned, the BWP state can be recovered only by depending on the UE through a resynchronization or reconstruction process, the excessive duration can be up to several seconds, and the downlink data service rate presents a serious pit drop phenomenon observed from the UE side during the period, so that the use experience of a user is greatly influenced.

In a more serious case, if a dedicated BWP does not have a frequency domain range containing Coreset0 and is configured with a common Coreset resource specific to the BWP, if the UE does not actively initiate uplink data transmission, the UE cannot recover and a "call drop" phenomenon occurs.

In order to solve the above technical problem, an embodiment of the present disclosure provides a method for switching a partial bandwidth BWP, as shown in fig. 2, the method includes:

s201, notifying a user to perform BWP switching;

s202, determining whether the user completes BWP switching according to the fact that the error rate in the preset uplink and downlink continuous scheduling times reaches a preset value;

s203, if the BWP switching is not finished, increasing the DCI repetition times of the user and indicating the user to perform the BWP switching again; or terminating the user BWP handover.

In step S201, when it is detected that the state attribute of the user reaches a preset condition, the user is notified to perform BWP switching.

As shown in fig. 3, after the RRC connection and the service bearer are successfully established, the base station may detect a status attribute of the user, for example, detect whether the UE is in weak coverage, perform an RRC reconfiguration procedure if the UE is in weak coverage, indicate the UE to enable the PDCCH repetition function in the reconfiguration, and enable the "DCI repetition number" in the DCI format to take effect after the activation, so as to indicate the user to enable the PDCCH repetition effect function.

Meanwhile, a notification carrying the downlink control information DCI repetition times is sent to the user, so that the user can perform BWP switching according to the DCI repetition times.

In step S202, it may be determined that the user does not complete BWP handover according to whether the detected error rate within the preset number of consecutive uplink and downlink scheduling times reaches a preset value.

If the user is determined not to finish the BWP switching, increasing the DCI repetition times on the basis of the original configured DCI repetition times, and informing the user so that the user can perform the BWP switching again according to the increased DCI repetition times.

Meanwhile, after determining that the user does not complete the BWP handover, the PDCCH aggregation level of the user may be increased to improve the service priority of the user.

By the method, whether the user BWP switching is successful can be judged, the DCI repetition times can be increased to perform the BWP switching again or the switching is selected to be terminated under the condition of unsuccessful, and the phenomenon that packet loss is caused for several seconds and even UE call drop is avoided due to the fact that the user is inconsistent with the BWP state of the base station is avoided.

For the purpose of illustrating the present solution in detail, the present disclosure also provides an embodiment,

when the base station needs to perform BWP switching, mapping an initial CCE aggregation level AggregationLevel and a repetition number pdcchRepetitioninNum and informing UE to perform switching according to the condition that the current SRS SINR is smaller than a first threshold or the condition that the current downlink scheduling BLER is larger than a second threshold.

An example of the mapping of the initial CCE aggregation level AggregationLevel and the number of repetitions pdcchrepetition num is shown in table 1:

in this embodiment, the base station may further determine whether the BWP prohibit switching timer BWPSwtichProhibitTimer is running, and if the BWP prohibit switching timer is running, the procedure is ended, where the BWP prohibit switching timer may be set when the user is notified of the BWP switching for the first time, or when the user is notified of the BWP switching again after the BWP switch failure is determined.

In this embodiment, the base station instructs the UE to perform DCI 0_1 (single-cell PUSCH scheduling) or DCI 1_1 (single-cell PUSCH scheduling), and the instruction carries the PDCCH repetition validation enabling function and the PDCCH repetition number indication (pdcchrepetition num).

After the preset time, the base station determines that the user does not finish the BWP handover by determining whether the bit error rate within the uplink and downlink continuous scheduling times reaches a preset value.

In an embodiment, the number of uplink and downlink continuous scheduling is set to be 5, the error rate is 100%, and if the preset value is reached, the user is considered to have not completed BWP handover, and then the CCE aggregation level and the repetition number for BWP handover are increased, and then BWP m to BWP n handover is performed through DCI 0_1/1_ 1.

Otherwise, the BWP switching is considered to be successful, and the process is ended.

In another embodiment, before the handover, the BWP performs uplink and downlink continuous scheduling, where the number of times of uplink and downlink continuous scheduling is 5, and the error rate is 50%, and if the number of times of uplink and downlink continuous scheduling is satisfied, the user state is considered to be abnormal, the uplink and downlink related scheduling of the user is suspended, and the user is waited to initiate random access or RRC reestablishment.

Otherwise, the base station considers that the user does not complete BWP handover, and further increases the CCE aggregation level and repetition number for BWP handover, and then performs BWP m to BWP n handover through DCI 0_1/1_ 1.

It can be seen from the embodiments that, the base station performs verification after BWP handover by using a BWP handover decision algorithm (determining whether handover is successful) to find that the states of the UE and the base station active BWP are inconsistent as soon as possible, and can actively perform fallback after detecting that the states are inconsistent, and try to further save, so as to avoid packet loss which may be several seconds long, and even UE drop call, thereby improving the probability of BWP handover for the user.

The embodiment of the present disclosure further provides a base station device, where the base station device includes:

a notification module for notifying a user of BWP switching;

The foregoing description has been directed to specific embodiments of this disclosure. Other embodiments are within the scope of the following claims. In some cases, the actions or steps recited in the claims may be performed in a different order than in the embodiments and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some embodiments, multitasking and parallel processing may also be possible or may be advantageous.

Other embodiments of the present description will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This specification is intended to cover any variations, uses, or adaptations of the specification following, in general, the principles of the specification and including such departures from the present disclosure as come within known or customary practice within the art to which the specification pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the specification being indicated by the following claims.

It will be understood that the present description is not limited to the precise arrangements described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present description is limited only by the appended claims.

The above description is only a preferred embodiment of the present disclosure, and should not be taken as limiting the present disclosure, and any modifications, equivalents, improvements, etc. made within the spirit and principle of the present disclosure should be included in the scope of the present disclosure.

Claims

1. A method for switching a partial bandwidth BWP, the method comprising:

informing a user to perform BWP switching;

2. The method of claim 1, further comprising:

and when detecting that the state attribute of the user reaches a preset condition, informing the user to perform BWP switching.

3. The method according to claim 1, wherein the notifying the user of the BWP handover specifically comprises:

4. The method of claim 1, wherein the increasing the number of repetitions of the DCI for the user and instructing the user to perform BWP handover again comprises:

5. The method of claim 1, further comprising:

and if determining that the user does not complete the BWP handover, increasing the PDCCH aggregation level of the user.

6. The method according to claim 1, wherein terminating the user BWP handover specifically comprises:

a BWP prohibit switch timer is set such that if the BWP switch times out, the BWP prohibit switch is executed.

7. A base station apparatus, characterized in that,

a notification module for notifying a user of BWP switching;

8. The base station device of claim 7, wherein the processing module is further configured to increase the PDCCH aggregation level for the user when the base station device determines that the user does not complete BWP handover.

9. The base station device of claim 7, wherein the processing module is specifically configured to increase the DCI repetition number on the basis of the original configured DCI repetition number, and notify the user, so that the user performs BWP handover again according to the newly increased DCI repetition number.

10. The base station apparatus of claim 7, wherein the processing module is further configured to set a BWP prohibit switching timer such that if the BWP switching times out, the BWP prohibit switching is performed.