# US 8,787,280 B2 · Methods and apparatus for WAN assisted contention detection and resolution in peer to peer networks > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,787,280 B2 - Document ID: US8787280B2 - Status: Granted - Kind: B2 - Application number: 13/229,399 - Filed: 2011-09-09 - Published: 2013-03-14 - Granted: 2014-07-22 - Earliest claimed: 2011-09-09 - Assignees: QUALCOMM Incorporated - Applicants: Shailesh Patil; Hua Wang; Xinzhou Wu; Junyi Li; Thomas J. Richardson - Inventors: Shailesh Patil; Hua Wang; Xinzhou Wu; Junyi Li; Thomas J. Richardson - Web page: https://patentgrep.com/patent/US8787280B2 ## CPC - H04W 74/0858: {collision detection} - H04W 4/70: Services for machine-to-machine communication [M2M] or machine type communication [MTC] - H04W 76/11: Allocation or use of connection identifiers - H04W 74/085: {collision avoidance} - H04W 76/14: Direct-mode setup - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Various methods and apparatus are directed to collision detection and/or avoidance regarding peer to peer connection identifiers. A wireless communications device broadcasts a signal indicating its acquired connection identifier in one of two alternative blocks. A base station monitors peer to peer signaling in its coverage area and tracks the usage of peer to peer connection identifiers by pairs of devices. The base station detects when multiple pairs of devices are using the same peer to peer connection identifier. The base station provides assistance to the peer to peer network to avoid a collision or facilitate rapid collision detection by the peer to peer devices. In one approach the base station sends an instruction for a connection to switch its connection identifier. In another approach the base station sends a connection a message to bias its selection as to which of the two alternative blocks to use for transmission. ## Claims ### Claim 1 A method of operating a base station, the method comprising: tracking usage of connection identifiers for a peer to peer connection by pairs of communications devices; and performing an operation to reduce the risk of collisions or increase the probability of collision detection when it is detected that multiple pairs of communications devices within the coverage area of said base station are using the same connection identifier for a peer to peer connection. ### Claim 2 (depends on 1) The method of claim 1, wherein said operation is a collision avoidance operation including: instructing one of the multiple pairs of communications devices detected to be using the same connection identifier to switch to a different connection identifier. ### Claim 3 (depends on 1) The method of claim 1, wherein said operation is an operation to increase the probability of collision detection including: sending a first message to a first pair of devices using the same connection identifier to bias use of connection signaling transmission resources by said first pair of devices to a first subset of resources corresponding to said connection identifier. ### Claim 4 (depends on 3) The method of claim 3, wherein said operation further includes: sending a second message to a second pair of devices using the same connection identifier to bias use of connection signaling resources to a second subset of resources corresponding to said connection identifier. ### Claim 5 (depends on 4) The method of claim 4, wherein said first and second subsets of resources are sets of tone-symbols, said first message controlling the first pair of devices to transmit signals on tone-symbols in said first subset of resources more than on tone-symbols in said second subset of resources. ### Claim 6 (depends on 5) The method of claim 5, wherein said second message controls the second pair of devices to transmit signals on tone-symbols in said second subset of resources more than on tone-symbols in said first subset. ### Claim 7 A base station comprising: means for tracking usage of connection identifiers for a peer to peer connection by pairs of communications devices; and means for performing an operation to reduce the risk of collisions or increase the probability of collision detection when it is detected that multiple pairs of communications devices within the coverage area of said base station are using the same connection identifier for a peer to peer connection. ### Claim 8 (depends on 7) The base station of claim 7, wherein said means for performing an operation to reduce the risk of collisions or increase the probability of collision detection includes means for performing a collision avoidance operation, and wherein said means for performing a collision avoidance operation includes: means for instructing one of the multiple pairs of communications devices detected to be using the same connection identifier to switch to a different connection identifier. ### Claim 9 (depends on 7) The base station of claim 7, wherein said means for performing an operation to reduce the risk of collisions or increase the probability of collision detection includes means for performing an operation to increase the probability of collision detection, and wherein said means for performing an operation to increase the probability of collision detection includes: means for sending a first message to a first pair of devices using the same connection identifier to bias use of connection signaling transmission resources by said first pair of devices to a first subset of resources corresponding to said connection identifier. ### Claim 10 (depends on 9) The base station of claim 9, said means for increasing the probability of collision detection further includes: means for sending a second message to a second pair of devices using the same connection identifier to bias use of connection signaling resources to a second subset of resources corresponding to said connection identifier. ### Claim 11 A computer program product for use in a base station, the computer program product comprising: a non-transitory computer readable medium comprising: code for causing at least one computer to track usage of connection identifiers for a peer to peer connection by pairs of communications devices; and code for causing said at least one computer to perform an operation to reduce the risk of collisions or increase the probability of collision detection when it is detected that multiple pairs of communications devices within the coverage area of said base station are using the same connection identifier for a peer to peer connection. ### Claim 12 A base station comprising: at least one processor configured to: track usage of connection identifiers for a peer to peer connection by pairs of communications devices; and perform an operation to reduce the risk of collisions or increase the probability of collision detection when it is detected that multiple pairs of communications devices within the coverage area of said base station are using the same connection identifier for a peer to peer connection ; and memory coupled to said at least one processor. ### Claim 13 (depends on 12) The base station of claim 12, wherein said at least one processor is configured to perform an operation to reduce the risk of collisions, as part of being configured to perform an operation to reduce the risk of collisions or increase the probability of collision detection, and wherein said at least one processor is configured to instruct one of the multiple pairs of communications devices detected to be using the same connection identifier to switch to a different connection identifier, as part of being configured to perform an operation to reduce the risk of collisions. ### Claim 14 (depends on 12) The base station of claim 12, wherein said at least one processor is configured to perform an operation to increase the probability of collision detection, as part of being configured to perform an operation to reduce the risk of collisions or increase the probability of collision detection, wherein said at least one processor is configured to send a first message to a first pair of devices using the same connection identifier to bias use of connection signaling transmission resources by said first pair of devices to a first subset of resources corresponding to said connection identifier, as part of being configured to increase the probability of collision detection. ### Claim 15 (depends on 14) The base station of claim 14, wherein said at least one processor is further configured to send a second message to a second pair of devices using the same connection identifier to bias use of connection signaling resources to a second subset of resources corresponding to said connection identifier, as part of being configured to increase the probability of collision detection.