# US 2013/0156023 A1 · Methods and Apparatus for Efficiently Synchronizing a Transmitter and a Receiver in a Communication System > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0156023 A1 - Document ID: US20130156023A1 - Status: Published application - Kind: A1 - Application number: 13/525,245 - Filed: 2012-06-15 - Published: 2013-06-20 - Earliest claimed: 2004-12-22 - Assignees: QUALCOMM Incorporated - Inventors: Gavin Horn - Web page: https://patentgrep.com/patent/US20130156023A1 ## CPC - H04L 7/00: Arrangements for synchronising receiver with transmitter {(synchronisation of generators of electric oscillations or pulses H03L7/00)} - H04W 56/001: {Synchronization between nodes} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract The disclosed embodiments provide methods and systems for synchronizing a transmitter and a receiver. In one embodiment, a method for synchronizing a transmitter and a receiver includes the transmitter performing a reset operation, and the receiver responding by performing a reset operation. In another embodiment, a method for synchronizing a transmitter and a receiver includes the receiver performing a reset operation, and the transmitter responding by performing a reset operation. The reset indicator includes toggling a reset indicator. ## Claims ### Claim 1 A method of resetting a transmitter (Tx) entity, the method comprising: transmitting an initial plurality of frames to a receiver (Rx) entity, each of the plurality of frames comprising a header having a Tx reset indicator field having been set to a first state as part of a previously performed Tx entity reset operation; selectively performing a further Tx entity reset operation; and in response to performing the further Tx entity reset operation, transmitting a subsequent plurality of frames to the Rx entity, each of the subsequent plurality of frames comprising the header having the Tx reset indicator field in the header set to a second state to indicate that the Tx entity has performed the Tx entity reset operation, and wherein each of the initial plurality of frames and each of the subsequent plurality of frames further comprises data for use in one or more other operations. ### Claim 2 (depends on 1) The method of claim 1, and further comprising: receiving a reset request message from the Rx entity, the reset request message comprising an Rx entity reset indicator that is set to indicate that the Rx entity has performed an Rx entity reset operation; and wherein selectively performing the further Tx entity reset operation comprises initiating the further Tx entity reset operation based, at least in part, on the Rx entity reset indicator. ### Claim 3 (depends on 1) The method of claim 1, wherein the further Tx entity reset operation comprises: resetting a send state variable; and clearing a retransmission buffer. ### Claim 4 (depends on 3) The method of claim 3, wherein the send state variable comprises information about a sequence number of a next data unit to be sent. ### Claim 5 (depends on 1) The method of claim 1, wherein the Tx reset indicator field comprises a data bit that is operatively toggled to selectively represent the first state or the second state. ### Claim 6 An apparatus for use in resetting a transmitter (Tx) entity, the apparatus comprising: means for initiating transmission of an initial plurality of frames to a receiver (Rx) entity, each of the plurality of frames comprising a header having a Tx reset indicator field having been set to a first state as part of a previously performed Tx entity reset operation; means for selectively initiating a further Tx entity reset operation; and means for initiating transmission of a subsequent plurality of frames to the Rx entity subsequent the further Tx entity reset operation, each of the subsequent plurality of frames comprising the header having the Tx reset indicator field in the header set to a second state to indicate that the Tx entity has performed the Tx entity reset operation, and wherein each of the initial plurality of frames and each of the subsequent plurality of frames further comprises data for use in one or more other operations. ### Claim 7 (depends on 6) The apparatus of claim 6, and further comprising: means for receiving a reset request message from the Rx entity, the reset request message comprising an Rx entity reset indicator that is set to indicate that the Rx entity has performed an Rx entity reset operation; and wherein the means for selectively initiating the further Tx entity reset operation comprises means for initiating the further Tx entity reset operation based, at least in part, on the Rx entity reset indicator. ### Claim 8 (depends on 6) The apparatus of claim 6, wherein the means for selectively performing the further Tx entity reset operation comprises: means for initiating resetting of a send state variable; and means for initiating clearing of a retransmission buffer. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein the send state variable comprises information about a sequence number of a next data unit to be sent. ### Claim 10 (depends on 6) The apparatus of claim 6, wherein the Tx reset indicator field comprises a data bit that is operatively toggled to selectively represent the first state or the second state. ### Claim 11 An article comprising: a non-transitory computer-program product having code instructions stored thereon that are executable by a processor of a transmitter (Tx) entity to: initiate transmission of an initial plurality of frames to a receiver (Rx) entity, each of the plurality of frames comprising a header having a Tx reset indicator field having been set to a first state as part of a previously performed Tx entity reset operation; selectively initiate a further Tx entity reset operation; and subsequent the further Tx entity reset operation being performed, initiate transmission of a subsequent plurality of frames to the Rx entity, each of the subsequent plurality of frames comprising the header having the Tx reset indicator field in the header set to a second state to indicate that the Tx entity has performed the Tx entity reset operation, and wherein each of the initial plurality of frames and each of the subsequent plurality of frames further comprises data for use in one or more other operations. ### Claim 12 (depends on 11) The article of claim 11, the code instructions being further executable by the processor to: obtain a reset request message from the Rx entity, the reset request message comprising an Rx entity reset indicator that is set to indicate that the Rx entity has performed an Rx entity reset operation; and selectively initiate the further Tx entity reset operation based, at least in part, on the Rx entity reset indicator. ### Claim 13 (depends on 11) The article of claim 11, the code instructions being further executable by the processor, as part of the further Tx entity reset operation, to: initiate resetting of a send state variable; and initiate clearing of a retransmission buffer. ### Claim 14 (depends on 13) The article of claim 13, wherein the send state variable comprises information about a sequence number of a next data unit to be sent. ### Claim 15 (depends on 11) The article of claim 11, wherein the Tx reset indicator field comprises a data bit that is operatively toggled to selectively represent the first state or the second state. ### Claim 16 An apparatus for use in resetting a transmitter (Tx) entity, the apparatus comprising: a transmitter; and a processor to: initiate transmission, via the transmitter, of an initial plurality of frames to a receiver (Rx) entity, each of the plurality of frames comprising a header having a Tx reset indicator field having been set to a first state as part of a previously performed Tx entity reset operation; selectively initiate a further Tx entity reset operation; and subsequent the further Tx entity reset operation being performed, initiate transmission, via the transmitter, of a subsequent plurality of frames to the Rx entity, each of the subsequent plurality of frames comprising the header having the Tx reset indicator field in the header set to a second state to indicate that the Tx entity has performed the Tx entity reset operation, and wherein each of the initial plurality of frames and each of the subsequent plurality of frames further comprises data for use in one or more other operations. ### Claim 17 (depends on 16) The apparatus of claim 16, and further comprising: a receiver; and the processor to further obtain a reset request message from the Rx entity via the receiver, the reset request message comprising an Rx entity reset indicator that is set to indicate that the Rx entity has performed an Rx entity reset operation, and selectively initiate the further Tx entity reset operation based, at least in part, on the Rx entity reset indicator. ### Claim 18 (depends on 16) The apparatus of claim 16, the code instructions being further executable by the processor, as part of the further Tx entity reset operation, to: initiate resetting of a send state variable; and initiate clearing of a retransmission buffer. ### Claim 19 (depends on 18) The apparatus of claim 18, wherein the send state variable comprises information about a sequence number of a next data unit to be sent. ### Claim 20 (depends on 16) The apparatus of claim 16, wherein the Tx reset indicator field comprises a data bit that is operatively toggled to selectively represent the first state or the second state.