# US 2019/0174538 A1 · Data Transmission Technique for a Contention Channel > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0174538 A1 - Document ID: US20190174538A1 - Status: Published application - Kind: A1 - Application number: 16/324,336 - Filed: 2016-08-10 - Published: 2019-06-06 - Earliest claimed: 2016-08-10 - Assignees: Telefonaktiebolaget LM Ericsson (publ) - Applicants: Telefonaktiebolaget LM Ericsson (publ) - Inventors: Pål Frenger; Erik Eriksson; Jonas Fröberg Olsson; Martin Hessler - Web page: https://patentgrep.com/patent/US20190174538A1 ## CPC - H04W 74/08: Non-scheduled access, e.g. ALOHA (hybrid access H04W74/02) - H04L 5/0055: {Physical resource allocation for ACK/NACK (for physical mapping arrangements in ARQ protocols H04L1/1861)} - H04W 74/002: {Transmission of channel access control information} - H04W 76/11: Allocation or use of connection identifiers - H04W 72/20: Control channels or signalling for resource management - H04W 72/21: in the uplink direction of a wireless link, i.e. towards the network - 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 A technique for transmitting data (504) from a first station to a second station on a contention-based radio channel is described. As to a method aspect of the technique, the first station obtains a transmit identifier (506) for the first station from a set of transmit identifiers; transmits control information (502) including the transmit identifier (506) to the second station; and transmits the data (504) to the second station according to the control information (502), wherein the data includes a station identifier (508) for the first station, the station identifier (508) or a combination of the station identifier and the transmit identifier (506) being indicative of the first station. ## Claims ### Claim at position 1 1-41. (canceled) ### Claim 42 A device for transmitting data from a first station to a second station on a contention-based radio channel, the device comprising: a processor and a memory, the memory containing one or more programs executable by the processor wherein the device is configured to: obtain a transmit identifier for the first station from a set of transmit identifiers; transmit control information including the transmit identifier to the second station; and transmit the data to the second station according to the control information, wherein the data includes a station identifier for the first station, the station identifier or a combination of the station identifier and the transmit identifier being indicative of the first station. ### Claim 43 (depends on 42) The device of claim 42, configured to obtain the transmit identifier by: receiving from the second station the set of transmit identifiers; generating, as the transmit identifier for the first station, at least one of a pseudo-random number from the set of transmit identifiers and a hash value in the set of transmit identifiers; or receiving from the second station the transmit identifier for the first station. ### Claim 44 (depends on 42) The device of claim 42, further configured to receive, and/or listen for receiving, a response to the data transmission from the second station, the response including or implying the transmit identifier for the first station, wherein the response includes or implies an acknowledgment, ACK, for the data being successfully received at the second station or a negative acknowledgment, NACK, for the data not being successfully received at the second station. ### Claim 45 (depends on 44) The device of claim 44, further configured to retransmit the data to the second station, wherein retransmitting the data includes retransmitting control information including the transmit identifier, wherein the transmitted data is encoded according to a first redundancy version indicated in the transmitted control information, and the retransmitted data is encoded according to a second redundancy version, which is other than the first redundancy version and indicated in the retransmitted control information. ### Claim 46 (depends on 45) The device of claim 45, wherein the data is retransmitted, if the response, or another message including the transmit identifier, includes or implies: a negative acknowledgment, NACK, for the data not being successfully received at the second station; or a scheduling grant for the retransmission. ### Claim 47 (depends on 45) The device of claim 45, wherein the data is retransmitted on a contention-free radio resource. ### Claim 48 (depends on 44) The device of claim 44, wherein the data transmission starts a response timer and, wherein the device is configured, upon expiry of the response timer without having received the response including the transmit identifier from the second station, to: release the transmit identifier for the first station; and/or repeat at least the transmission of the data from the first station to the second station. ### Claim 49 (depends on 44) The device of claim 44, configured to receive the response starts or restarts a transmit identifier timer, and further configured to, upon expiry of the transmit identifier timer, release the transmit identifier for the first station. ### Claim 50 (depends on 42) The device method of claim 42, further configured to: receive a control message from the second station for releasing the transmit identifier, wherein the control message includes or implies the transmit identifier; and release the transmit identifier for the first station in response to the control message. ### Claim 51 (depends on 42) The device of claim 42, wherein a cardinality of the set of transmit identifiers is less than a number of stations associated with the second station. ### Claim 52 (depends on 42) The device of claim 42, wherein a size of the transmit identifier corresponds to a first number of bits, and a size of the station identifier corresponds to a second number of bits that is greater than the first number of bits. ### Claim 53 (depends on 42) The device of claim 42, wherein the control information is transmitted according to a first transmission format, and the data is transmitted according to a second transmission format that is different from the first transmission format. ### Claim 54 (depends on 42) The device of claim 42, wherein the control information is indicative of at least one of a modulation scheme, a coding scheme, a HARQ process number, new data and a redundancy version. ### Claim 55 (depends on 42) The device of claim 42, wherein the data is at least one of transmitted on a contention-based radio resource and retransmitted on a contention-based radio resource, wherein at least one of the transmission and the retransmission on the contention-based radio resource is based on a contention process, and wherein the contention-based radio resource uses unlicensed spectrum, and wherein the contention process comprises at least one of: including the transmit identifier in the control information of the data transmission; performing a clear channel assessment, CCA, of the contention-based radio resource; and performing a backoff mechanism. ### Claim 56 A device for receiving data from a first station at a second station on a contention-based radio channel, the device comprising: a processor and a memory, the memory containing one or more programs executable by the processor wherein the device is configured to: receive control information including a transmit identifier from the first station; maintain, based on the received transmit identifier, a list of transmit identifiers from a set of transmit identifiers; and receive the data from the first station according to the control information, wherein the data includes a station identifier for the first station, the station identifier or a combination of the station identifier and the transmit identifier being indicative of the first station. ### Claim 57 (depends on 56) The device of claim 56, further configured to: determine a transmit identifier from the set of transmit identities, which is not on the list, and send the determined transmit identifier to the first station. ### Claim 58 (depends on 56) The device of claim 56, wherein the list is indicative of transmit identifiers for which control information has been successfully received and data has not been successfully received, the device further configured to: buffer soft-bits representing the not successfully received data in association with the transmit identifier; and transmit a negative acknowledgment, NACK, including the transmit identifier to the first station. ### Claim 59 A method of transmitting data from a first station to a second station on a contention-based radio channel, the method comprising or triggering the following steps performed by the first station: obtaining a transmit identifier for the first station from a set of transmit identifiers; transmitting control information including the transmit identifier to the second station; and transmitting the data to the second station according to the control information, wherein the data includes a station identifier for the first station, the station identifier or a combination of the station identifier and the transmit identifier being indicative of the first station. ### Claim 60 A method of receiving data from a first station at a second station on a contention-based radio channel, the method comprising or triggering the following steps performed by the second station: receiving control information including a transmit identifier from the first station; maintaining, based on the received transmit identifier, a list of transmit identifiers from a set of transmit identifiers; and receiving the data from the first station according to the control information, wherein the data includes a station identifier for the first station, the station identifier or a combination of the station identifier and the transmit identifier being indicative of the first station.