WO2019085042A1

WO2019085042A1 - Communication method, base station, and apparatus having storage function

Info

Publication number: WO2019085042A1
Application number: PCT/CN2017/111641
Authority: WO
Inventors: Yuling OUYANG; Ting Zhou; Xin XIA; Zhenhong Li
Original assignee: Huizhou Tcl Mobile Communication Co., Ltd
Priority date: 2017-10-30
Filing date: 2017-11-17
Publication date: 2019-05-09
Also published as: CN109729551A; CN109729551B

Abstract

A communication method, a base station and an apparatus having a storage function are provided. The communication method includes: a first base station and a second base station establishing different communication links to a user equipment; when receiving communication status information of the user equipment, one of the first base station and the second base station transmitting the communication status information to the other of the first base station and the second base station, in such a way that the other of the first base station and the second base station performs operations corresponding to the communication status information. It is possible to prevent the transmitting buffer from overflowing, reduce a waste of resources, and reduce a time delay.

Description

COMMUNICATION METHOD, BASE STATION, AND APPARATUS HAVING STORAGE FUNCTION

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to communication technology, and in particular relate to a communication method, a base station, and an apparatus having a storage function.

BACKGROUND

With the development of technology, people have higher and higher expectations for wireless communication. In order to achieve URLLC (Ultra-reliable and low latency communications) , RAN (Radio Access Network) supports packet duplication across multiple links to ensure high reliability. For NR-NR (New Radio) dual-connectivity (the dual-connectivity may be interpreted as connecting one same user device to two base stations simultaneously) technology, one of key motivations of a duplication function is to take profit of different links to transmit a plurality of packets from the always fastest link to meet the latency requirement.

However, the configuration of the dual-connectivity may result in two potential issues. On one hand, a “slower” packet transmitted in one link may not able to keep up with another link, and thus it may be “stuck” in a transmitter. On the other hand, a RLC (Radio Link Control) buffer in the transmitter may overflow, and a RLC ARQ (Automatic Repeat-request) window of a receiver may mismatch with an actual receiving status of a RLC SDU (service Data Unit) .

SUMMARY

The technical problem to be solved by the present disclosure is to provide a communication method, a base station and an apparatus having a storage function, in which the communication quality may be improved when using at least two links for data communication.

In order to solve the above-mentioned problems, in accordance with a first aspect, the present disclosure provides a communication method, the communication method comprises: a first base station and a second base station establishing different communication links to a user equipment; when receiving communication status information of the user equipment, one of the first base station and the second base station transmitting the communication status information to the other of the first base station and the second base station, in such a way that the other of the first base station and the second base station performs operations corresponding to the communication status information.

In order to solve the above-mentioned problems, in accordance with a second aspect, the present disclosure provides a communication method. The communication method comprises: establishing a first communication link between a first base station and a user equipment; the first base station acquiring current communication status information, and transmitting the communication status information to a second base station, in such a way that the second base station performs operations corresponding to the communication status information; wherein a second communication link is established between the second base station and the user equipment; the first communication link and the second communication link are communication links backuping each other.

In order to solve the above-mentioned problems, in accordance with a third aspect, the present disclosure provides a base station. The base station comprises a processor, a storage, and a communication circuit; the processor being coupled to the storage and the communication circuit, and configured to perform the method described above.

In order to solve the above-mentioned problems, in accordance with a third aspect, the present disclosure provides an apparatus having a storage function. The apparatus has program data stored therein, the program data is executable to perform the method described above.

The subsequent advantages of the present disclosure may be achieved: compared with the prior art, in the present embodiment, during the data communication when using at least two links, when receiving the communication status information of the user equipment acting as a corresponding communication node, the base station in one link may share the communication status information to the base station in the other link, and thus the base station in the other link may acquire the communication status in other links, and perform the operation corresponding to the communication status information, thereby improving the communication quality.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart of a communication method according to one embodiment of the present disclosure.

FIG. 2 is a flow chart of a communication method according to another embodiment of the present disclosure.

FIG. 3 is a schematic view illustrating the downlink communication of the communication method according to one embodiment of the present disclosure.

FIG. 4 is a schematic view illustrating a serial number mapping table between PDCP (Packet Data Convergence Protocol) PDU (Protocol Data Unit) and the RLC SDU.

FIG. 5 is a schematic view illustrating the uplink communication of the communication method according to one embodiment of the present disclosure.

FIG. 6 is a schematic view illustrating the data conformance report according to one embodiment of the present disclosure.

FIG. 7 is a block diagram illustrating a base station according to one embodiment of the present disclosure.

FIG. 8 is a block diagram illustrating the connection between the first station, the second station and the user equipment.

FIG. 9 is a structural view of an apparatus having a storage function according to one embodiment of the present disclosure.

DETAILED DESCRIPTION

Technical solutions of embodiments of the present disclosure will be described clearly and completely with reference to the attached drawings illustrating the embodiments of the present disclosure. Obviously, the embodiments described herein are only a part of but not all of the embodiments of the present disclosure. All other embodiments that can be obtained by those of ordinary skill in the art from the embodiments of the present disclosure without making creative efforts shall fall within the scope of the present disclosure.

Referring to FIG. 1, a flow chart of a communication method according to one embodiment of the present disclosure is depicted in FIG. 1. The communication method of the present disclosure may include the following blocks.

At block 101: a first base station and a second base station may respectively establish different communication links to a user equipment.

In a specific application case, in order to ensure reliability of the communication, a same PDCP PDU packet may be transmitted via different communication links, i.e., by dual-connectivity communication or multiple-connectivity communication. In this application case, the first base station and the second base station may respectively establish different communication links to the same user equipment. In this way, the same packet may be transmitted via the two different communication links, thereby improving the reliability of the communication.

At block 102: when receiving communication status information of the user equipment, one of the first base station and the second base station may transmit the communication status information to the other of the first base station and the second base station, in such a way that the other of the first base station and the second base station may perform operations corresponding to the communication status information.

In a specific application case, the first base station may be a master base station, while the second base station may be a subordinate base station of the first base station. Acting as the master base station, the first base station may receive the communication status information transmitted from the user equipment via the communication link established between the user equipment and the first base station, or the master base station may detect a communication status of the communication link established to the user equipment. In this application case, the first base station, the second base station and the user equipment may be configured in a downlink mode, and the first base station and the second base station may transmit a same PDCP PDU to the user equipment via different communication links respectively. The communication status information may include a serial number of the PDCP PDU transmitted from the first base station and/or the second base station and successfully received by the user equipment. After receiving the communication status information, the first base station may read the serial number of the PDCP PDU included therein, and transmit the serial number of the PDCP PDU to the second base station. In the present application case, the first base station and the second base station may be communicated with each other via an Xn interface.

The PDCP PDU may be transmitted from a PDCP entity of the first base station acting as the master base station to a RLC entity of the first base station and a RLC entity of the second base station. The RLC entity of the first base station and that of the second base station may segment the received PDCP PDU based on the communication status of the corresponding base station; in this way, at least one RLC SDU with an individual serial number may be formed. Thus, a serial number mapping table between the PDCP PDU and the PLC SDU may be present in the first base station and the second base station, and configured to track and record the serial number of the at least one RLC SDU corresponding to the PDCP PDU with a certain serial number.

Therefore, after receiving the serial number of the PDCP PDU successfully received by the user equipment, the RLC entity of the first base station and that of the second base station may respectively identify the serial number of the corresponding RLC SDU from the individual serial number mapping table between the PDCP PDU and the RLC SDU, and check whether the RLC SDU with the identified serial number has been transmitted; if not, the RLC SDU may be discarded, in order to make room for the buffer of the transmission of subsequent data.

In another specific application case, the first base station, the second base station and the user equipment may be configured in an uplink mode, and the PDCP entity of the first base station may generate a data conformance report based on a PDCP PDU status transmitted from the user equipment and successfully received by the first base station, and further transmit the data conformance report to the RLC entity of the first base station and that of the second base station. In this application case, the data conformance report may include a serial number of a first PDCP PDU received successfully by the first base station, and a quantity of the PDUs transmitted in a same link with the first PDCP PDU. The RLC entity of the first base station and the RLC entity of the second base station may calculate serial numbers of PDUs to be received based on the data conformance report. In the present application case, the first base station and the second base station may be communicated with each other via the Xn interface. In the present application case, the first base station may receive the PDCP PDU transmitted from the user equipment, meanwhile receive the serial number mapping table between the PDCP PDU and the RLC SDU transmitted from the user equipment, and further transmit the mapping table to the second base station via the Xn interface. The RLC entity of the first base station and that of the second base station may indentify the corresponding serial number of the RLC SDU, based on the mapping table and the received PDCP PDU, and check whether an automatic repeat-request (ARQ) window matches with the serial number of the RLC SDU. If not, the automatic repeat-request window may be adjusted to a position matching with the serial number of the RLC SDU. For example, when m PDUs have been received successfully from a first link at present, and the serial number of the first PDU received from the first link is SNn, then the serial number of a next PDU to be received may be SNn+m. However, if a second link is stuck at this time, the PDU may not be successfully transmitted and an automatic repeat-request window of the second base station may be still located at the position of SNn. In this case, the RLC entity of the second base station may move up the automatic repeat-request window by m positions of PDUs, and correspond to the PDU with the serial number of SNn+m, and thus the second base station may receive the SDU corresponding to the PDU.

It can be understood from the above description that, the RLC entity of the first base station and that of the second base station may receive the communication status information transmitted from the PDCP entity of the first base station, make adjustments in time based on the automatic repeat-request window, discard the data packet which does not need to be transmitted, and adjust the position of the corresponding automatic repeat-request window. In this way, it is possible to effectively avoid the buffer overflow of a transmitting end, and meanwhile avoid a waste of resources caused by retransmission request due to the mismatch between the position of the automatic repeat-request window and the actual status .

Referring to FIG. 2, a flow chart of a communication method according to another embodiment of the present disclosure is depicted in FIG. 2. The communication method of the present disclosure may include the following blocks.

At block 201: a first communication link may be established between a first base station and a user equipment.

In a specific application case, the first communication link may be established between the first base station and the user equipment, while a second communication link may be established between a second base station and the user equipment. In specific, the first communication link may include a PDCP entity and a RLC entity of the first base station, a first RLC entity and a PDCP entity of the user equipment. The communication link may include a PDCP entity and a RLC entity of the second base station, a second RLC entity and the PDCP entity of the user equipment. In the present application case, the first base station may be the master base station, while the second base station may be the subordinate base station of the first base station.

Referring to FIG. 3, a schematic view illustrating the downlink communication of the communication method according to one embodiment of the present disclosure is depicted in FIG. 3. When performing the downlink communication, the PDCP entity of the first base station acting as the master base station may duplicate the SDU to be transmitted to the user equipment, in such a way that two groups of duplicated SDUs may be formed. The first base station may further transmit the two groups of SDUs via two different communication links. In specific, one group of SDUs may be transmitted to the first RLC entity of the user equipment via the RLC entity of the master base station, and further transmitted to the PDCP entity of the user equipment via the first RLC entity of the user equipment. While the other group of SDUs may be transmitted to the second RLC entity of the user equipment via the RLC entity of the second base station (i.e., the subordinate base station) , and further transmitted to the PDCP entity of the user equipment via the second RLC entity of the user equipment. In the present application case, the PDCP entity of the first base station may transmit the other group of SDUs to be transmitted to the user equipment to the RLC entity of the second base station (i.e., the subordinate base station) via the Xn interface. In other application case, the PDCP entity of the first base station may transmit the other group of SDUs to be transmitted to the user equipment to the RLC entity of the second base station (i.e., the subordinate base station) via other interfaces.

When receiving the SDUs transmitted from the PDCP entity of the first base station, the RLC entity of the first base station (i.e., the master base station) and the RLC entity of the second base station (i.e., the subordinate base station) may segment each of the SDUs based on current communication statuses and communication conditions respectively of individual base stations. In this case, one PDCP PDU may be segmented into at least one RLC SDU to transmit. Each PDCP PDU may have a serial number for identification. Likewise, each RLC SDU may also have a serial number for identification. The serial numbers of the PDCP PDUs should be different from each other, in order to distinguish from each other. However, the serial numbers of the RLC SDUs may be the same with each other, as long as the serial numbers respectively of a plurality of RLC SDUs segmented from the same PDCP PDU by the same RLC entity are different from each other. In this way, the RLC entity of the fist base station and the RLC entity of the second base station may each have a mapping table between the serial numbers of the PDCP PDUs and the serial number of at least one RLC SDU formed by segmenting the SDU transmitted from the PDCP entity of the first base station.

Referring to FIG. 4, a schematic view illustrating a serial number mapping table between the PDCP PDU and the RLC SDU is depicted in FIG. 4. As is shown in FIG. 4, the serial number of the PDCP entity may be namely the serial number of the PDCP PDU, and the serial number of the RLC entity may be namely the serial number of the RLC SDU. In this embodiment, one PDCP PDU serial number may correspond to a plurality of RLC SDU serial numbers; for example, PDCP serial number 1 may correspond to three serial numbers including RLC SN1, RLC SN2 and RLC SN3. However, in other embodiment, it is also possible for one PDCP PDU serial number to correspond to one RLC SDU serial number; for example, PDCP serial number 2 may correspond to RLC SNa. The first base station and the second base station may each have the mapping table shown in FIG. 4 stored therein.

The first RLC entity and the second RLC entity of the user equipment may respectively receive the RLC SDUs from the RLC entity of the first base station and the RLC entity of the second base station, recombine the RLC SDUs in order to regain the original PDCP PDUs, and further transmit the recombined RLC SDUs to the PDCP entity of the user equipment.

Referring to FIG. 5, a schematic view illustrating the uplink communication of the communication method according to one embodiment of the present disclosure is depicted in FIG. 5. When performing the uplink communication, the PDCP entity of the user equipment may duplicate the PDCP PDU to be transmitted to the first base station and the second base station in such a way that two groups of duplicated SDUs may be formed. The PDCP entity of the user equipment may further transmit the two groups of SDUs via two different communication links. In specific, one group of SDUs may be transmitted to the RLC entity of the first base station via the first RLC entity of the user equipment, and further transmitted to the PDCP entity of the first base station via the RLC entity of the first base station. While the other group of SDUs may be transmitted to the RLC entity of the second base station via the second RLC entity of the user equipment, and further transmitted to the PDCP entity of the first base station via the RLC entity of the second base station. In the present application case, the RLC entity of the second base station may transmit the other group of SDUs to the PDCP entity of the first base station via the Xn interface.

The first RLC entity and the second RLC entity of the user equipment may each include an automatic repeat-request window. Only when a receiving position of the automatic repeat-request window matches with the received RLC SDU serial number, will the first RLC entity receive the RLC SDU transmitted from the RLC entity of the first base station and the second RLC entity receive the RLC SDU transmitted from the RLC entity of the second base station.

After receiving the SDUs transmitted from the PDCP entity of the user equipment, the first RLC entity and the second RLC entity of the user equipment may segment each of the SDUs based on the current communication statuses and the communication conditions respectively of individual base stations. In this case, one PDCP PDU may be segmented into at least one RLC SDU to transmit. Each PDCP PDU may have a serial number for identification. Likewise, each RLC SDU may also have a serial number for identification. The serial numbers of the PDCP PDUs should be different from each other, in order to distinguish from each other. The serial numbers of the RLC SDUs may be the same with each other, as long as the serial numbers respectively of a plurality of RLC SDUs segmented from the same PDCP PDU by the same RLC entity are different from each other. In this way, the first RLC entity and the second RLC entity of the user equipment may each have a mapping table between the serial numbers of the PDCP PDUs and the serial number of at least one RLC SDU formed by segmenting the SDU transmitted from the PDCP entity of the user equipment. The mapping table is shown in FIG. 4, and will not be described in detail any more.

The RLC entity of the first base station and the RLC entity of the second base station may each include an automatic repeat-request window. Only when the receiving position of the automatic repeat-request window matches with the received RLC SDU serial number, will the RLC entity of the first base station and the RLC entity of the second base station receive the RLC SDUs transmitted from the first RLC entity and the second RLC entity of the user equipment.

At block 202: when receiving communication status information of the user equipment via the first communication link, the first base station may transmit the communication status information to the second base station, in such a way that the first base station and the second base station may perform operations corresponding to the communication status information.

Referring to FIG. 3 again, the schematic view illustrating the downlink communication of the communication method according to one embodiment of the present disclosure is depicted in FIG. 3. In a specific application case, the first base station acting as the master base station may receive communication status information transmitted from the user equipment. In the present application case, the user equipment may generate a PDCP status report based on the PDCP PDU received successfully. Wherein the PDCP status report may include a serial number of the PDCP PDU received successfully. After receiving the PDCP status report, the PDCP of the first base station may read the serial number of the PDCP PDU included therein, and transmit the serial number to the RLC entity of the first base station and the RLC entity of the second base station. In this embodiment, the PDCP entity of the first base station may transmit the serial number to the RLC entity of the second base station via the Xn interface.

In the present application case, the user equipment may generate the PDCP status report in the light of a preset time period; for example, the user equipment may generate the PDCP status report periodically based on the PDCP PDUs received successfully during the time period, and further transmit the PDCP status report to the PDCP entity of the first base station. In another application case, it is also possible for the user equipment to generate the PDCP status report in the light of a preset quantity of the PDCP PDUs; for example, the user equipment may generate the PDCP status report everytime the preset quantity of PDUs are received, and further transmit the PDCP status report to the PDCP entity of the first base station. In another application case, it is also possible for the user equipment to generate the PDCP status report in the light of a preset quantity of bytes of the received PDUs; for example, the user equipment may generate the PDCP status report when the quantity of bytes of the received PDUs reaches to the preset value, and further transmit the PDCP status report to the PDCP entity of the first base station. In a further application case, it may also possible for the user equipment to generate the PDCP status report in response to request information transmitted from the first base station and/or the second base station, and further transmit the PDCP status reports to the PDCP entity of the first base station.

The RLC entity of the first base station and the RLC entity of the second base station may each have a serial number mapping table between the PDCP PDU and the RLC SDU stored therein. The RLC entity of the first base station and the RLC entity of the second base station may identify the corresponding serial number of the RLC SDU based on the serial number of the received PDCP PDU, and check whether the RLC SDU with the serial number has been transmitted; if not, the RLC SDU with the serial number may be discarded.

Meanwhile, the PDCP entity of the user equipment may generate a data conformance report based on the PDCP PDUs received successfully. In this case, the data conformance report may include the serial numbers and the quantity of the PDCP PDUs received successfully. The PDCP entity of the user equipment may transmit the data conformance report to the first RLC entity and the second RLC entity of the user equipment. The first RLC entity and the second RLC entity of the user equipment may read the serial numbers respectively of the PDCP PDUs in the data conformance report. In the present application case, the serial numbers of the RLC SDUs received by the first RLC entity and the second RLC entity of the user equipment may include identification information, and the first RLC entity and the second RLC entity of the user equipment may determine which PDCP PDU the RLC SDU corresponds to based on the identification information, thereby acquiring correspondence between the serial numbers of the PDCP PDUs and the serial numbers of the RLC SDUs. Accordingly, the first RLC entity and the second RLC entity of the user equipment may determine whether the current positions of the individual automatic repeat-request windows match with the RLC SDUs to be received based on the quantity of the PDCP PDUs in the data conformance report. If not, the positions of the individual automatic repeat-request windows may be adjusted to match with the RLC SDUs to be received.

In another application case, the RLC entity of the first base station may transmit the serial number mapping table between the PDCP PDU and the RLC SDU stored therein to the first RLC entity of the user equipment, while the RLC entity of the second base station may transmit the serial number mapping table between the PDCP PDU and the RLC SDU stored therein to the second RLC entity of the user equipment. In this way, the first RLC entity and the second RLC entity of the user equipment may determine whether the positions of the individual automatic repeat-request windows match with the RLC SDUs to be received by searching in the mapping table based on the serial numbers in the data conformance report. If the positions of the individual automatic repeat-request windows mismatch with the RLC SDUs to be received, the positions of the individual automatic repeat-request windows may be adjusted to match with the RLC SDUs to be received.

Referring to FIG. 6, a schematic view illustrating the data conformance report according to one embodiment of the present disclosure is depicted in FIG. 6. As is shown in FIG. 6, the data conformance report may include a Star PDCP SN and a PDCP SN NUM. The Star PDCP SN may refer to the serial number of the first PDCP PDU received by the user equipment from the faster one of two links. The PDCP SN NUM may refer to the quantity of the PDUs received by the PDPC entity of the user equipment from the RLC entity of the base station included in the faster one of the two links. Based on the serial number of the first PDCP PDU received by the user equipment and the quantity of the PDUs received successfully and transmitted from the same link with the first PDCP PDU received by the user equipment, the serial number of the PDU to be received may be acquired, and thus it is possible to estimate or identify the corresponding serial number of the RLC SDU from the mapping table. In this way, the RLC entity of the user equipment may perform a corresponding check based on the serial numbers of the RLC SDUs, and further adjust the positions of the individual automatic repeat-request windows.

In another application case, after adjusting the positions of the automatic repeat-request windows, the first RLC entity and the second RLC entity of the user equipment may update the serial number mapping table between the PDCP PDU and the RLC SDU, and delete the serial numbers of the SDUs which are discarded from the mapping table.

Referring to FIG. 5, the schematic view illustrating the uplink communication of the communication method according to one embodiment of the present disclosure is depicted in FIG. 5. In a specific application case, the first base station may act as the master base station, and the PDCP entity of the first base station may receive the PDU transmitted from the user equipment, and further transmit the communication status information to the PDCP entity of the user equipment. In the present application case, the PDCP entity of the first base station may generate a PDCP status report based on the PDCP PDUs received successfully. The PDCP status report may include the serial numbers of the PDCP PDUs received successfully. The PDCP entity of the user equipment may receive the PDCP status report, read the serial numbers of the PDCP PDUs therein, and further transmit the serial numbers to the first RLC entity and the second RLC entity of the user equipment.

In the present application case, the PDCP entity of the first base station may generate the PDCP status report in the light of a preset time period; for example, the user equipment may generate the PDCP status report periodically based on the PDCP PDUs received successfully during the time period, and further transmit the PDCP status report to the PDCP entity of the user equipment. In another application case, it is also possible for the PDCP entity of the first base station to generate the PDCP status report in the light of a preset quantity of the PDP PDUs; for example, the PDCP entity of the first base station may generate the PDCP status report everytime the preset quantity of PDUs are received, and further transmit the PDCP status report to the PDCP entity of the user equipment. In another application case, it is also possible for the PDCP entity of the first base station to generate the PDCP status report in the light of a preset quantity of bytes of the received PDUs; for example, the PDCP entity of the first base station may generate the PDCP status report when the quantity of bytes of the received PDUs reaches to the preset value, and further transmit the PDCP status report to the PDCP entity of the user equipment. In another application case, it may also possible for the PDCP entity of the first base station to generate the PDCP status report in response to request information transmitted from the first base station and/or the second base station, and further transmit the PDCP status report to the PDCP entity of the user equipment.

The first RLC entity and the second RLC entity of the user equipment may each have a serial number mapping table between the PDCP PDU and the RLC SDU stored therein. The first RLC entity and the second RLC entity of the user equipment may identify the corresponding serial number of the RLC SDU based on the serial number of the received PDCP PDU, and check whether the RLC SDU with the serial number has been transmitted; if not, the RLC SDUs with these serial numbers may be discarded.

Meanwhile, the PDCP entity of the first base station may generate a data conformance report based on the PDCP PDUs received successfully. In this case, the data conformance report may include serial numbers and the quantity of the PDCP PDUs received successfully. The PDCP entity of the first base station may transmit the data conformance report to the RLC entity of the first base station and the RLC entity of the second base station. In the present application case, the PDCP entity of the first base station may transmit the data conformance report to the RLC entity of the second base station via the Xn interface. The RLC entity of the first base station and the RLC entity of the second base station may read the serial numbers of the PDCP PDUs in the data conformance report. In the present application case, the serial numbers of the RLC SDUs received by the RLC entity of the first base station and the RLC entity of the second base station may include identification information, and the RLC entity of the first base station and the RLC entity of the second base station may determine which PDCP PDU the RLC SDU corresponds to based on the identification information, thereby acquiring the correspondence between the serial numbers of the PDCP PDUs and the serial numbers of the RLC SDUs. Accordingly, the RLC entity of the first base station and the RLC entity of the second base station may determine whether the current positions of the individual automatic repeat-request windows match with the RLC SDUs to be received based on the serial numbers and the quantity of the PDCP PDUs in the data conformance report. If the current positions of the respective automatic repeat-request windows mismatch with the RLC SDUs to be received, the positions of the individual automatic repeat-request windows may be adjusted to match with the RLC SDUs to be received.

In another application case, the first RLC entity and the second RLC entity of the user equipment may transmit the serial number mapping table between the PDCP PDU and the RLC SDU stored therein to the RLC entity of the first base station and the RLC entity of the second base station. In this way, the RLC entity of the first base station and the RLC entity of the second base station may determine whether the positions of the individual automatic repeat-request windows match with the RLC SDUs to be received by searching in the mapping table based on the serial numbers in the data conformance report. If the positions of the individual automatic repeat-request windows mismatch with the RLC SDUs to be received, the positions of the individual automatic repeat-request windows may be adjusted to match with the RLC SDUs to be received.

Referring to FIG. 6, the schematic view of illustrating the data conformance report according to one embodiment of the present disclosure is depicted in FIG. 6. The configuration of the data conformance report generated by the PDCP entity of the first base station may be also shown in FIG. 6. The data conformance report may include a Star PDCP SN and a PDCP SN NUM. The Star PDCP SN may refer to the serial number of the first PDCP PDU received by the PDCP of the first base station from the faster one of two links. The PDCP SN NUM may refer to the quantity of the PDUs received by the PDCP entity of the first base station from the RLC entity included in the faster one of the two links. Based on the serial number of the first PDCP PDU received by the first base station and the quantity of the PDUs and received successfully and transmitted via the same link with the first PDCP PDU received by the first base station, the serial number of the PDU to be received may be acquired, and thus it is possible to estimate or identify the corresponding serial number of the RLC SDU from the mapping table. In this way, the RLC entity of the first base station and the RLC entity of the second base station may perform the corresponding check based on the serial numbers of the RLC SDUs, and further adjust the positions of the individual automatic repeat-request windows.

In another application case, after adjusting the positions of the automatic repeat-request windows, the RLC entity of the first base station and the RLC entity of the second base station may update the serial number mapping table between the PDCP PDU and the RLC SDU, and delete the serial number of the SDU which is discarded from the mapping table.

In the present application case, the first base station and the second base station may each be implemented as a new radio base station. However, in other application case, it is also possible that only one of the first base station and the second base station is implemented as the new radio base station. It is also possible that the first base station and the second base station may each be implemented as the other base station, such as a long-term evolution base station.

In other application case, it is also possible for the second base station to be the master base station, and the first base station to be the subordinate base station of the second base station. The operating methods and principles in this case may be substantially the same as those described above, as long as the function of the first base station exchanges with that of the second base station. And thus, it will not be described in detail any more.

In the present application case, the user equipment may be connected to the first base station and the second base station using the dual-connectivity mode. However, in other application case, it is also possible for the user equipment to be connected to the first base station and the second base station using the multiple-connectivity mode; that is, one user equipment may be simultaneously connected to a plurality of base stations.

In the present application case, the first base station and the second base station may both support a separation mode. In this way, the PDCP entity of the first base station and the RLC entity of the second base station may communicate with each other via the Xn interface. In other application case, it may possible that only one of the first base station and the second base station supports the separation mode.

It can be seen from that, the user equipment, the first base station and the second base station in this embodiment may use the dual-connectivity mode to connect to each other, and a receiver of the PDCP PDU may inform a transmitter of the PDCP PDU of transmitting the serial number of the PDU received successfully. The transmitter of the PDCP PDU may identify the serial number of the corresponding RLC SDU based on the serial number of the PDU, and discard the SDU with the serial number but not yet transmitted; in this way, it is possible to make room for the buffer of the transmitter, thereby avoiding the buffer overflow and the stuck in the link of the buffer. At the same time, the receiver of the PDCP PDU may inform the RLC entity of the corresponding base station of the serial number of the RLC SDU should be received currently, and adjust the position of the automatic repeat-request window to make the position of the window match with the RLC SDU to be received. In this way, it is possible to reduce unnecessary retransmission requests, save the radio resources, and reduce the time delay.

Referring to FIG. 7, a block diagram illustrating a base station according to one embodiment of the present disclosure is depicted in FIG. 7. The base station 10 may include a processor 11, a storage 12 and a communication circuit 13. The processor 11 may be respectively coupled to the storage 12 and the communication circuit 13.

Referring to FIG. 8, a block diagram illustrating the connection between the first station, the second station and the user equipment is depicted in FIG. 8. The configurations of the first base station 20 and the second base station 30 may be as shown in FIG. 7, and will not be described in detail any more. A communication circuit 23 of the first base station 20 may be communicated with a communication circuit 33 of the second base station 30. The communication circuit 23 of the first base station 20 and the communication circuit 33 of the second base station 30 may be communicated with the user equipment 40.

When performing the downlink communication, a processor 21 of the first base station 20 may transmit the serial number of the PDU to be transmitted to the user equipment to a storage 22 for storage, duplicate the PDU to be transmitted in such a way that two groups of duplicated PDUs may be formed, and further transmit one group of the PDUs to the second base station 30 via the communication circuit 23. The second base station 30 may receive the group of PDUs via the communication circuit 33. The processor 21 of the first base station 20 and a processor 31 of the second base station 30 may each segment each of the PDUs needing to be transmitted into at least one SDU based on current communication statuses and communication conditions respectively of individual base stations. The at least one SDU may have the individual serial number. The

processors

21 and 31 may generate the mapping tables based on the correspondence between the serial numbers of the PDUs and the serial numbers of the SDUs formed by segmenting the PDUs, and the mapping tables may be further stored in the corresponding

storages

22 and 32.

When the communication circuit 23 of the first base station receives the PDPC PDU status report transmitted from the user equipment, the processor 21 may read the serial number of the PDCP PDU successfully received and included therein, and transmit the serial number to the second base station 30 via the communication circuit 23. The processor 21 of the first base station 20 and the processor 31 of the second base station 30 may identify the corresponding serial number of the RLC SDU from the mapping table stored respectively in the

storages

22 and 32 based on the received serial number of the PDCP PDU, and check whether the RLC SDU with the serial number has been transmitted; if not, the RLC SDU may be discarded.

When performing the uplink communication, the processor 21 of the first base station 20 may generate a PDCP PDU status report based on the status of the PDCP PDU received by the communication circuit 23, and further transmit the status report to the user equipment 40 via the communication circuit 23. Meanwhile, the processor 21 may generate a data conformance report, and transmit the data conformance report to the second base station 30 via the communication circuit 23. In the present application case, the serial number of the RLC SDU received by the first base station 20 and the second base station 30 may include identification information, and the RLC entity of the first base station and the RLC entity of the second base station may determine which PDCP PDU the RLC SDU corresponds to based on the identification information, thereby acquiring the correspondence between the serial numbers of the PDCP PDUs and the serial numbers of the RLC SDUs. The data conformance report may include the serial number of the first PDCP PDU received by the first base station 20, and the quantity of the PDUs received successfully and transmitted via the same link with the first PDCP PDU received by the first base station.

The processor 21 of the first base station 10 and the processor 31 of the second base station 30 may estimate or identify the corresponding serial number of the RLC SDU from the mapping table pre-stored in the

storages

22 and 32 based on the data conformance report. The processor 21 of the first base station 10 and the processor 31 of the second base station 30 may correspondingly adjust receiving requests respectively of the communication circuits 23 and 33 based on the serial number, in order to make the receiving requests match with a current receiving status of the PDU.

In the present application, the first base station may act as the master base station. However, in other application case, it is also possible for the second base station to be the master base station, and the first base station to be the subordinate base station of the second base station. The operating methods and principles in this case may be substantially the same as those described above, as long as the function of the first base station exchanges with that of the second base station. And thus, it will not be described in detail any more.

Therefore, the base station in the present embodiment may discard the SDU which does not need to be transmitted and which has not been transmitted yet, based on the receiving status of the PDCP PDU during the downlink communication, and make room for the buffer. Further, the base station may adjust the receiving request of the communication circuit in time during the uplink communication, thereby avoiding the time delay and a waste of resources caused by unnecessary retransmissions.

Referring to FIG. 9, a structural view of an apparatus having a storage function according to one embodiment of the present disclosure is depicted in FIG. 9. The apparatus 50 having the storage function may have at least one program or instruction 51 stored therein. The program or instruction 51 may be configured to execute the communication method as shown in FIGS. 1-2. In one embodiment, the apparatus having the storage function may be a memory chip or a hard disk in a terminal, or other read-write storage device such as a mobile hard disk, a flash drive, a light disk, or the like. The apparatus may also be a server or the like.

Therefore, in the present embodiment, the program or instruction stored in the apparatus having the storage function may delete the SDU corresponding to the serial number of the PDU received successfully and not yet transmitted by acquiring the serial number of the PDU received successfully to make room for transmission buffer, and correspondingly adjust the position of the automatic repeat-request window by acquiring the quantity of the PDUs received successfully and initial serial number of the PDU, thereby avoiding a waste of resources and reducing the time delay.

Different from the technical solution in the prior art that the RLC entity of the transmitter may inform the RLC entity of the receiver of the correct position of the current automatic repeat-request window, in the present disclosure, the PDCP entity of the transmitter may generate the data conformance report including the serial number of the first PDU received by the PDCP entity, and the quantity of the PDUs successfully received and transmitted in a same link with the first PDU received by the PDCP entity, and inform the RLC entity of the receiver. In this way, it is possible to reduce the consumption of the resources, and reduce the possibility of time delay.

The above description depicts merely some exemplary embodiments of the disclosure, and is not intended to limit the scope of the disclosure. Any equivalent structure or flow transformations made to the disclosure, or any direct or indirect applications of the disclosure on other related fields, shall all be covered within the protection of the disclosure.

Claims

A communication method, comprising:

a first base station and a second base station establishing different communication links to a user equipment;

when receiving communication status information of the user equipment, one of the first base station and the second base station transmitting the communication status information to the other of the first base station and the second base station, in such a way that the other of the first base station and the second base station performs operations corresponding to the communication status information.
A communication method, comprising:

establishing a first communication link between a first base station and a user equipment;

the first base station acquiring current communication status information, and transmitting the communication status information to a second base station, in such a way that the second base station performs operations corresponding to the communication status information;

wherein a second communication link is established between the second base station and the user equipment; the first communication link and the second communication link are communication links backuping each other.
The method of claim 2, wherein

the first base station is a master base station, while the second base station is a subordinate base station of the first base station;

the first base station acquiring the current communication status information, and transmitting the current communication status information to the second base station comprises:

a packet data convergence protocol entity of the first base station receiving the communication status information of the user equipment;

the packet data convergence protocol entity of the first base station transmitting the communication status information to a radio link control entity of the first base station and a radio link control entity of the second base station.
The method of claim 3, wherein

the packet data convergence protocol entity of the first base station transmitting the communication status information to the radio link control entity of the second base station via an Xn interface.
The method of claim 3, further comprising:

the packet data convergence protocol entity of the first base station transmitting data to be transmitted to the radio link control entity of the first base station and the radio link control entity of the second base station, in such a way that the radio link control entity of the first base station transmits the data to be transmitted to the user equipment via the first communication link, and that the radio link control entity of the second base station transmits the data to be transmitted to the user equipment via the second communication link;

wherein the second base station performs the operations corresponding to the communication status information comprises: when the communication status information indicates that all or parts of the data to be transmitted in the packet data convergence protocol entity of the first base station have been transmitted to the user equipment successfully, informing the packet data convergence protocol entity of the second base station of discarding the all or parts of the data to be transmitted, and not transmitting the all or parts of the data to be transmitted to the user equipment via the second communication link;

when the communication status information indicates that all or parts of the data to be transmitted in the packet data convergence protocol entity of the second base station have been transmitted to the user equipment successfully, informing the packet data convergence protocol entity of the first base station of discarding the all or parts of the data to be transmitted, and not transmitting the all or parts of the data to be transmitted to the user equipment via the first communication link.
The method of claim 5, wherein

the communication status information comprises a packet data convergence protocol data unit status report including a serial number of the packet data convergence protocol data unit received successfully by the user equipment.
The method of claim 6, wherein

the packet data convergence protocol entities respectively of the first base station and the second base station each has a mapping table between the serial number of the packet data convergence protocol data unit and a serial number of the radio link control service data unit;

wherein the second base station performs the operations corresponding to the communication status information comprises:

identifying a serial number of the radio link control service data unit in the mapping table, based on the serial number of the packet data convergence protocol data unit received successfully by the user equipment;

checking whether the radio link control service data unit with the identified serial number has been transmitted; when the radio link control service data unit has not yet been transmitted, discarding the radio link control service data unit.
The method of claim 7, further comprising:

when the radio link control service data unit has been discarded, the radio link control entities respectively of the first base station and the second base station updating the mapping table.
The method of claim 2, wherein the first base station acquiring the current communication status information and transmitting the current communication status information to the second base station comprises:

when acquiring the communication status information of the first base station, the first base station transmitting the communication status information to the second base station.
The method of claim 9, wherein

the first base station is a master base station, while the second base station is a subordinate base station of the first base station;

the transmitting the current communication status information to the second base station, in such a way that the second base station performs the operations corresponding to the communication status information comprises:

a packet data convergence protocol entity of the first base station transmitting the communication status information to a radio link control entity of the first base station and a radio link control entity of the second base station, in such a way that the second base station performs the operations corresponding to the communication status information.
The method of claim 10, wherein

the packet data convergence protocol entity of the first base station transmitting the communication status information to the radio link control entity of the second base station comprises:

the packet data convergence protocol entity of the first base station generating a data conformance report based on the communication status information, and transmitting the data conformance report to the radio link control entity of the second base station.
The method of claim 11, wherein the data conformance report comprises: a serial number of a first packet data convergence protocol data unit received successfully by the first base station, and a quantity of packet data convergence protocol data units transmitted successfully in a same link with the first packet data convergence protocol data unit.
The method of claim 12, wherein the second base station performs the operations corresponding to the communication status information comprises:

calculating a serial number of the packet data convergence protocol data unit corresponding to an automatic repeat-request window via the data conformance data report;

comparing a current receiving position of the automatic repeat-request window with the serial number the packet data convergence protocol data unit; when the receiving position is located behind the serial number, moving up the receiving position to a position corresponding to the serial number.
The method of claim 3, wherein the first base station, the second base station and the user equipment are in dual-connectivity mode.
The method of claim 3, wherein at least one of the first base station and the second base station supports a separation mode.
The method of claim 3, wherein the first base station and the second base station are each implemented as a new radio base station.
The method of claim 2, wherein the communication status information is transmitted from the user equipment in the light of a preset time period.
The method of claim 2, wherein the communication status information is transmitted from the user equipment in the light of a preset quantity of the received protocol data units.
The method of claim 2, wherein the communication status information is transmitted from the user equipment in the light of a preset quantity of bytes of the received protocol data units.
The method of claim 2, wherein the communication status information is transmitted from the user equipment based on request information transmitted from the first base station and/or the second base station.
A base station, comprising a processor, a storage, and a communication circuit;

the processor being coupled to the storage and the communication circuit, and configured to perform the method of any one of claims 1-20.
An apparatus having a storage function, having program data stored therein, the program data is executable to perform the method of any one of claims 1-20.