# US 2018/0324642 A1 · Packet duplication at a packet data convergence protocol (pdcp) entity > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0324642 A1 - Document ID: US20180324642A1 - Status: Published application - Kind: A1 - Application number: 15/970,047 - Filed: 2018-05-03 - Published: 2018-11-08 - Earliest claimed: 2017-05-05 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Yu-Ting Yu; Gavin Bernard Horn; Chih-Ping Li - Web page: https://patentgrep.com/patent/US20180324642A1 ## CPC - H04W 28/065: {using assembly or disassembly of packets} - H04L 1/08: by repeating transmission, e.g. Verdan system {(H04L1/1858 and H04L1/189 take precedence)} - H04L 1/1835: {Buffer management} - H04L 1/22: using redundant apparatus to increase reliability - H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - H04W 36/0055: {Transmission or use of information for re-establishing the radio link} - H04W 76/15: Setup of multiple wireless link connections - H04L 1/0009: {by adapting the channel coding (H04L1/1812 takes precedence)} - H04L 1/04: using frequency diversity - H04L 5/001: {the frequencies being arranged in component carriers} - H04L 47/32: by discarding or delaying data units, e.g. packets or frames - H04L 2001/0096: {Channel splitting in point-to-point links} - H04W 28/0278: {using buffer status reports (dynamic wireless traffic scheduling definition H04W72/12)} - H04W 76/20: Manipulation of established connections - 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) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Techniques are described for operating procedures associated with packet duplication. A packet data protocol convergence protocol (PDCP) entity of a transmitting device may duplicate a received packet to form a set of copied packets. Each packet in the set of copied packets may include the information of the received packet. Each packet of the set of copied packets may be transmitted using a different radio link control (RLC) entity. Procedures are described for configuring duplication bearers. Procedures are described for activating or deactivating packet duplication. Procedures are described for handling RLC entities at deactivation. Procedures are described for discarding some duplicate packets after a packet has been successfully decoded by a receiving device. Procedures are described for delaying transmission of duplicate packets to improve efficient use of communication resources. Procedures are described for buffer status report (BSR) reporting for duplication bearers. ## Claims ### Claim 1 A method for wireless communication, comprising: receiving a configuration of a bearer to support packet duplication by for a packet data convergence protocol (PDCP) entity; determining an activation status of the packet duplication for the bearer; duplicating a first PDCP packet to create a second PDCP packet that is a copy of the first PDCP packet based at least in part on the activation status of the packet duplication for the bearer; and forwarding the first PDCP packet to a first radio link control (RLC) entity and the second PDCP packet to a second RLC entity. ### Claim 2 (depends on 1) The method of claim 1, further comprising: determining that a dynamic duplication parameter satisfies an activation threshold; and activating the duplication of packets by the PDCP entity based at least in part on the dynamic duplication parameter satisfying the activation threshold. ### Claim 3 (depends on 2) The method of claim 2, wherein the dynamic duplication parameter includes, a packet loss rate associated with the first RLC entity, a packet loss rate associated with the second RLC entity, a data rate associated with the first RLC entity, a data rate associated with the second RLC entity, a channel quality indicator associated with the first RLC entity, a channel quality indicator associated with the second RLC entity, an application packet type, a transport block size associated with the first RLC entity, a transport block size associated with the second RLC entity, or combinations thereof. ### Claim 4 (depends on 1) The method of claim 1, wherein at least one of the first PDCP packet of the first RLC entity or the second PDCP packet of the second RLC entity includes a logical channel identifier (LCID), a logical channel group identifier (LCG ID), a buffer size of the first RLC entity, a buffer size of the second RLC entity, padding, or combinations thereof. ### Claim 5 (depends on 1) The method of claim 1, further comprising: receiving, via the first RLC entity, an acknowledgement (ACK) indicating that the first PDCP packet was received by a receiving device; and refraining from transmitting the second PDCP packet via the second RLC entity based at least in part on receiving the ACK. ### Claim 6 (depends on 5) The method of claim 5, further comprising: identifying a current left edge and a next sequence number of the first RLC entity; and determining a state variable for the second RLC entity based at least in part on the current left edge and the next sequence number of the first RLC entity. ### Claim 7 (depends on 5) The method of claim 5, further comprising: adjusting a state variable of the second RLC entity based at least in part on an updated state variable of the first RLC entity; and discarding packets stored in a buffer of the second RLC entity based at least in part on adjusting the state variable of the second RLC entity. ### Claim 8 (depends on 7) The method of claim 7, wherein: the updated state variable of the first RLC entity is indicated to the second RLC entity by an indication from the PDCP entity, the first RLC entity, or a radio resource control (RRC) entity. ### Claim 9 (depends on 1) The method of claim 1, further comprising: activating a timer based at least in part on forwarding the first data packet to the first RLC entity. ### Claim 10 (depends on 9) The method of claim 9, further comprising: receiving an acknowledgement (ACK) that the first PDCP packet was received by a receiving device before the timer expires; and discarding the second PDCP packet without forwarding the second PDCP packet to the second RLC entity based at least in part on receiving the ACK. ### Claim 11 (depends on 9) The method of claim 9, further comprising: determining that the timer expired without receiving an acknowledgement from a receiving device, wherein forwarding the second PDCP packet is based at least in part on the timer expiring without receiving the acknowledgement from the receiving device. ### Claim 12 (depends on 1) The method of claim 1, further comprising: transmitting the first PDCP packet using a first component carrier having a first frequency spectrum band, the first component carrier being mapped to the first RLC entity; and transmitting the second PDCP packet using a second component carrier having a second frequency spectrum band different from the first frequency spectrum band, the second component carrier being mapped to the second RLC entity. ### Claim 13 (depends on 12) The method of claim 12, further comprising: receiving a message indicating the mapping of the first RLC entity to the first component carrier and the second RLC entity to the second component, wherein transmitting the first PDCP packet and the second PDCP packet is based at least in part on the mapping. ### Claim 14 (depends on 1) The method of claim 1, further comprising: transmitting a first buffer status report (BSR) for the first RLC entity; and transmitting a second BSR for the second RLC entity. ### Claim 15 (depends on 1) The method of claim 1, further comprising: identifying a first buffer status for a first buffer of the first RLC entity and a second buffer status for a second buffer of the second RLC entity; and transmitting a single buffer status report that includes the first buffer status and the second buffer status. ### Claim 16 (depends on 1) The method of claim 1, further comprising: selecting the first RLC entity or the second RLC entity as a default RLC entity; and transmitting an identification of the default RLC entity to a receiving device. ### Claim 17 (depends on 1) The method of claim 1, wherein the first RLC entity and the second RLC entity are associated with carrier aggregation for communicating with a same base station. ### Claim 18 (depends on 1) The method of claim 1, wherein the first RLC entity is associated with a first base station and the second RLC entity is associated with a second base station different from the first base station for dual connectivity communication. ### Claim 19 (depends on 1) The method of claim 1, wherein the packet duplication includes a plurality of procedures for processing data at the PDCP entity that are different from procedures specified by other modes of operation of the PDCP entity. ### Claim 20 (depends on 1) The method of claim 1, further comprising: coordinating a forwarding of the first PDCP packet to the first RLC entity and the second PDCP packet to the second RLC entity based at least in part on a status of the first RLC entity and a status of the second RLC entity. ### Claim 21 (depends on 20) The method of claim 20, further comprising: configuring the status of the first RLC entity and the status of the second RLC entity based at least in part on activating packet duplication, deactivating packet duplication, or reactivating packet duplication. ### Claim 22 (depends on 20) The method of claim 20, wherein: the coordinating of the forwarding of the first PDCP packet and the second PDCP packet is based at least in part on delaying transmission of the second PDCP packet using a timer. ### Claim 23 A method for wireless communication by a user equipment (UE), comprising: receiving, from a base station, a condition for activating packet duplication, the condition including an indication of an activation parameter and an activation threshold; measuring the activation parameter associated with packet duplication; determining that the activation parameter satisfies the activation threshold; and transmitting an activation message to the base station indicating that duplicated packets are to be communicated by the UE based at least in part on determining that the activation parameter satisfies the activation threshold. ### Claim 24 (depends on 23) The method of claim 23, further comprising: duplicating, by a packet data convergence protocol (PDCP) entity of the UE, a first PDCP packet to create a second PDCP packet that is a copy of the first PDCP packet based at least in part on determining that the activation parameter satisfies the activation threshold. ### Claim 25 (depends on 24) The method of claim 24, further comprising: forwarding the first PDCP packet to a first RLC entity and the second PDCP packet to a second RLC entity different from the first RLC entity. ### Claim 26 (depends on 24) The method of claim 24, further comprising: transmitting the first PDCP packet and the second PDCP packet to the base station based at least in part on determining that the activation parameter satisfies the activation threshold. ### Claim 27 (depends on 23) The method of claim 23, wherein: the activation parameter is a packet loss rate or a channel quality indicator associated with a communication link between the base station and the UE. ### Claim 28 (depends on 23) The method of claim 23, further comprising: receiving an identification of a default RLC entity from the base station. ### Claim 29 An apparatus for wireless communication, comprising: a processor; memory in electronic communication with the processor; and instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to: receive a configuration of a bearer to support packet duplication by a packet data convergence protocol (PDCP) entity; determine an activation status of the packet duplication bearer; duplicate a first PDCP packet to create a second PDCP packet that is a copy of the first PDCP packet based at least in part on the activation status of the packet duplication for the bearer; and forward the first PDCP packet to a first radio link control (RLC) entity and the second PDCP packet to a second RLC entity. ### Claim 30 An apparatus for wireless communication, comprising: a processor; memory in electronic communication with the processor; and instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to: receive, from a base station, a condition for activating packet duplication, the condition including an indication of an activation parameter and an activation threshold; measure the activation parameter associated with packet duplication; determine the activation parameter satisfies the activation threshold; and transmit an activation message to the base station indicating that duplicated packets are to be communicated by the UE based at least in part on determining that the activation parameter satisfies the activation threshold.