# US 12,193,061 B2 · Contention based random access procedure for mobile communications > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,193,061 B2 - Document ID: US12193061B2 - Status: Granted - Kind: B2 - Application number: 17/590,832 - Filed: 2022-02-02 - Published: 2022-08-11 - Granted: 2025-01-07 - Earliest claimed: 2021-02-06 - Assignees: Deutsche Telekom AG - Applicants: Deutsche Telekom AG - Inventors: Thomas Paetzold - Web page: https://patentgrep.com/patent/US12193061B2 ## CPC - H04W 74/0833: Random access procedures, e.g. with 4-step access - H04W 74/0841: {with collision treatment} - H04W 74/002: {Transmission of channel access control information} - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract A method for a contention-based random access procedure includes: receiving, by a base station, a first scheduled transmission message of a mobile terminal; in response to receiving the first scheduled transmission message, setting up, by the base station, a contention resolution message, wherein the contention resolution message comprises a defined part of a hash value of a mobile terminal contention resolution identity; and transmitting, by the base station, the contention resolution message to the mobile terminal. ## Claims ### Claim 1 A method for a contention-based random access procedure, comprising: receiving, by a base station, a first scheduled transmission message of a mobile terminal, wherein the first scheduled transmission message comprises a medium access control (MAC) control element including a mobile terminal contention resolution identity; in response to receiving the first scheduled transmission message, setting up, by the base station, a contention resolution message, wherein the base station is an eNodeB of a 4G LTE network, wherein the contention resolution message is configured for transmission from the base station to the mobile terminal, wherein the contention resolution message comprises a defined part of a hash value of the mobile terminal contention resolution identity, wherein the hash value of the mobile terminal contention resolution identity is calculated by the base station using a hash algorithm, and wherein the defined part of the hash value is inserted by the base station into the contention resolution message; and transmitting, by the base station, the contention resolution message to the mobile terminal. ### Claim 2 (depends on 1) The method of claim 1, wherein the hash algorithm is public and known to the mobile terminal. ### Claim 3 (depends on 1) The method of claim 1, wherein the hash algorithm is SHA-256. ### Claim 4 (depends on 1) The method according to claim 1, wherein the defined part of the hash value of the mobile terminal contention resolution identity has the same size as the mobile terminal contention resolution identity. ### Claim 5 (depends on 1) The method of claim 1, wherein the mobile terminal contention resolution identity has a defined size of 40 bits, and the defined part of the hash value has the 40 least significant bits of the hash value of the mobile terminal contention resolution identity. ### Claim 6 (depends on 1) A non-transitory processor readable medium having stored thereon processor executable instructions, wherein the processor-executable instructions, when executed, facilitate performance of the method according to claim 1. ### Claim 7 A mobile communication system, comprising: a mobile terminal; and a base station, wherein the base station is an eNodeB of a 4G LTE network, and wherein the base station is configured to; receive a first scheduled transmission message of a mobile terminal, wherein the first scheduled transmission message comprises a medium access control (MAC) control element including a mobile terminal contention resolution identity; in response to receiving the first scheduled transmission message, set up a contention resolution message, wherein the contention resolution message is configured for transmission from the base station to the mobile terminal, wherein the contention resolution message comprises a defined part of a hash value of the mobile terminal contention resolution identity, wherein the hash value of the mobile terminal contention resolution identity is calculated by the base station using a hash algorithm, and wherein the defined part of the hash value is inserted by the base station into the contention resolution message; and transmit the contention resolution message to the mobile terminal. ### Claim 8 (depends on 7) The mobile communication system according to claim 7, wherein the mobile terminal is configured to: receive the contention resolution message from the base station; calculate its own hash value of the mobile terminal contention resolution identity included in the first scheduled transmission message using the hash algorithm; and check the mobile terminal contention resolution identity corresponding to the hash value calculated by the base station by comparing the defined part of the hash value calculated by the base station with a corresponding defined part of the hash value calculated by the mobile terminal. ### Claim 9 A base station for performing a contention-based random access procedure in a mobile communication system, wherein the base station is an eNodeB of a 4G LTE network, and wherein the base station comprises: a receiver configured to receive a first scheduled transmission message from a mobile terminal, wherein the first scheduled transmission message includes a medium access control (MAC) control element comprising a mobile terminal contention resolution identity; a processor configured to set up a contention resolution message in response to receiving the first scheduled transmission message, wherein the contention resolution message is configured for transmission from the base station to the mobile terminal, wherein the contention resolution message comprises a defined part of a hash value of the mobile terminal contention resolution identity, wherein the hash value of the mobile terminal contention resolution identity is calculated by the base station using a hash algorithm, and wherein the defined part of the hash value is inserted by the base station into the contention resolution message; and a transmitter configured to transmit the contention resolution message to the mobile terminal. ### Claim 10 A mobile terminal for performing a contention-based random access procedure in a mobile communication system, comprising: a transmitter configured to transmit a first scheduled transmission message to a base station, wherein the base station is an eNodeB of a 4G LTE network, and wherein the first scheduled transmission message comprises a medium access control (MAC) control element including a mobile terminal contention resolution identity; a receiver configured to receive a contention resolution message from the base station, wherein the contention resolution message comprises a defined part of a hash value of the mobile terminal contention resolution identity calculated by the base station; and a processor configured to: calculate its own hash value of the mobile terminal contention resolution identity; identify a part of the own hash value which corresponds to the defined part of the hash value calculated by the base station; and check the mobile terminal contention resolution identity corresponding to the hash value calculated by the base station by comparing the defined part of the hash value calculated by the base station with the corresponding defined part of the hash value calculated by the mobile terminal.