Improved uplink harq operation for prose-enabled ues participating in sidelink discovery operation

A user terminal operating a transmission protocol for

• uplink data packet transmission in a communication system, wherein a transmission counter is configured for the transmission protocol of the user terminal for counting the number of transmissions the user terminal has performed for a data packet, wherein the user terminal is configured with a first transmission counter parameter setting a maximum number of allowable transmissions of a data packet for the operation of the transmission counter,
• wherein the user terminal is configured to participate in sidelink discovery operation with other user terminals based on sidelink discovery gaps configured for the user equipment, wherein the user terminal cannot transmit and/or receive signals under control of the transmission protocol when participating in sidelink discovery operation during the sidelink discovery gaps,
• wherein the user terminal comprises:
• a processor configured to increment the transmission counter for a data packet when a retransmission of the data packet is triggered by the transmission protocol,
• the processor further configured to determine whether the triggered retransmission of the data packet was not performed because the transmission protocol operation collided with one of the sidelink discovery gaps, and
• in case of collision, the processor being further configured to use for the operation of the transmission counter of the data packet a second transmission counter parameter so as to increase the maximum number of allowable transmissions of the data packet for the transmission counter.

A method for operating a transmission protocol in a user terminal for uplink data packet transmission in a communication system, wherein a transmission counter is configured for the transmission protocol of the user terminal for counting the number of transmissions the user terminal has performed for a data packet,

• wherein the user terminal is configured to participate in sidelink discovery operation with other user terminals based on sidelink discovery gaps configured for the user equipment, wherein the user terminal cannot transmit and/or receive signals under control of the transmission protocol when participating in sidelink discovery operation during the sidelink discovery gaps,
• wherein the method comprises the following steps performed by the user terminal:
• determining whether a retransmission of a data packet, which is triggered by the transmission protocol, was not performed because the transmission protocol operation collided with one of the sidelink discovery gaps, and
• in case of collision, operating the transmission counter such that the colliding retransmission of the data packet does not result in an increment of the transmission counter of the transmission protocol for the data packet.