# US 2019/0174349 A1 · Congestion control method, base station, and user equipment > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0174349 A1 - Document ID: US20190174349A1 - Status: Published application - Kind: A1 - Application number: 16/251,936 - Filed: 2019-01-18 - Published: 2019-06-06 - Earliest claimed: 2016-07-22 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Jizhong SUN; Liang CHEN - Web page: https://patentgrep.com/patent/US20190174349A1 ## CPC - H04W 28/0289: {Congestion control (load shedding arrangements in network planning H04W16/08; performing reselection for handling the traffic H04W36/22; wireless traffic scheduling H04W72/12)} - H04W 24/10: Scheduling measurement reports {; Arrangements for measurement reports} - H04W 28/0205: {at the air interface (dynamic wireless traffic scheduling H04W72/12)} - H04W 28/06: Optimizing {the usage of the radio link}, e.g. header compression, information sizing {, discarding information (system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365)} - H04W 28/16: Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service] - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04W 72/52: based on load - H04W 72/535: {based on resource usage policies} - H04W 76/27: Transitions between radio resource control [RRC] states - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Embodiments of the present disclosure provide example congestion control methods, base stations, and user equipment. After determining that congestion control needs to be performed, a base station determines a congestion control policy, and determines, from UE in coverage of the base station, first UE that needs to perform adjustment according to the congestion control policy. The base station can then send the congestion control policy to the first UE, so that the first UE performs adjustment, to alleviate a congestion status of a PC5 interface. In this process, the base station performs centralized control on all UE in the coverage of the base station. ## Claims ### Claim 1 A congestion control method, comprising: receiving, by first user equipment (UE), indication information sent by a base station, wherein the indication information carries a congestion control policy, and wherein the congestion control policy is determined by the base station after the base station determines that congestion control needs to be performed on UE in coverage of the base station; and performing, by the first UE, adjustment according to the congestion control policy. ### Claim 2 (depends on 1) The method according to claim 1, further comprising: sending, by the first UE, a scheduling request; and in response to determining that the base station does not respond to the scheduling request after a timer expires or in response to determining that a PC5 interface of the first UE is congested, assisting, by the first UE, in congestion control. ### Claim 3 (depends on 2) The method according to claim 2, wherein the assisting, by the first UE, in congestion control comprises at least one of the following behaviors: a first behavior, wherein the first behavior comprises at least one of the first UE adjusting a packet transmission period or the first UE scheduling a sending period of an allocation request; a second behavior, wherein the second behavior comprises the first UE detecting whether the timer expires, and requesting a resource in a resource contention manner if the timer expires; a third behavior, wherein the third behavior comprises the first UE sending congestion status information of the PC5 interface to the base station; or a fourth behavior, wherein the fourth behavior comprises the first UE serving as UE whose transmission delay is greater than a congestion control delay threshold, and the first UE discarding a service packet. ### Claim 4 (depends on 1) The method according to claim 1, wherein the congestion control policy is used to instruct the first UE to perform adjustment in a measurement period, wherein the measurement period comprises Q resource pool scheduling allocation periods, wherein a Qith resource pool scheduling allocation period is any one of the Q resource pool scheduling allocation periods, wherein Q≥1, wherein 1≤Qi≤Q, and wherein both Q and Qi are integers. ### Claim 5 (depends on 4) The method according to claim 4, wherein the congestion control policy is used to instruct the first UE to adjust a current packet transmission period to a first packet transmission period in the measurement period, and wherein the performing, by the first UE, adjustment according to the congestion control policy, to alleviate a congestion status of a PC5 interface comprises: adjusting, by the first UE, the current packet transmission period to the first packet transmission period for the Qith resource pool scheduling allocation period, wherein the first packet transmission period is greater than the current packet transmission period. ### Claim 6 (depends on 5) The method according to claim 5, further comprising: adjusting, by the first UE, the first packet transmission period to a second packet transmission period, wherein the second packet transmission period is less than the first packet transmission period. ### Claim 7 (depends on 1) The method according to claim 1, further comprising: receiving, by the first UE, downlink control information (DCI) information sent by the base station, wherein the DCI information is used to instruct the first UE to serve as UE whose transmission delay is greater than a congestion control delay threshold. ### Claim 8 (depends on 4) The method according to claim 4, further comprising: determining, by the first UE, whether resource utilization in the measurement period is greater than a utilization threshold of congestion control; and if the resource utilization is greater than the utilization threshold of congestion control, sending congestion status information to the base station. ### Claim 9 (depends on 8) The method according to claim 8, wherein the determining, by the first UE, whether resource utilization in the measurement period is greater than a utilization threshold of congestion control comprises: determining, by the first UE, whether energy of each physical resource block (PRB) at each transmission time interval (TTI) in the measurement period is greater than an energy detection threshold; and if a ratio of a total quantity of PRBs whose energy is greater than the energy detection threshold of congestion control in the measurement period to a total quantity of PRBs in the measurement period is greater than a preset threshold, determining that utilization of a resource pool is greater than the utilization threshold of congestion control. ### Claim 10 (depends on 8) The method according to claim 8, wherein the determining, by the first UE, whether resource utilization in the measurement period is greater than a utilization threshold of congestion control comprises: determining, by the first UE, whether average energy of physical resource blocks (PRBs) in a subband PRB group in the measurement period is greater than an energy detection threshold; and if a ratio of a total quantity of PRBs whose energy is greater than the energy detection threshold of congestion control in the measurement period to a total quantity of PRBs in the measurement period is greater than a preset threshold, determining that utilization of a resource pool is greater than the utilization threshold of congestion control. ### Claim 11 (depends on 1) The method according to claim 1, wherein the receiving, by first UE, indication information sent by a base station comprises: receiving, by the first UE, the indication information sent by the base station by using downlink control information (DCI), radio resource control (RRC) signaling, or a system information block (SIB). ### Claim 12 A base station comprising at least one processor, a memory, a communications interface, and a system bus, wherein the memory and the communications interface are connected to the at least one processor by using the system bus to complete communication between each other, wherein the memory is configured to store a computer executable instruction, wherein the communications interface is configured to communicate with another device, and wherein the at least one processor is configured to run the computer executable instruction to cause the base station to perform, when the computer executable instruction is executed, the following operations: determining to perform congestion control on user equipment (UE) in coverage of the base station; determining a congestion control policy; determining first UE from the UE in the coverage of the base station, wherein the first UE is UE for which congestion needs to be alleviated according to the congestion control policy; and sending indication information to the first UE, wherein the indication information carries the congestion control policy, so that the first UE performs adjustment according to the congestion control policy. ### Claim 13 User equipment, wherein the user equipment (UE) is a first UE, and wherein the first UE comprises at least one processor, a memory, a communications interface, and a system bus, wherein the memory and the communications interface are connected to the at least one processor by using the system bus to complete communication between each other, wherein the memory is configured to store a computer executable instruction, wherein the communications interface is configured to communicate with another device, and wherein the at least one processor is configured to run the computer executable instruction to cause the first UE to perform, when the computer executable instruction is executed, the following operations: receiving indication information sent by a base station, wherein the indication information carries a congestion control policy, and wherein the congestion control policy is determined by the base station after the base station determines that congestion control needs to be performed on UE in coverage of the base station; and performing adjustment according to the congestion control policy.