Communication system and receiver
Provided is a radio communication technology that can achieve low latency, high reliability, and low jitter characteristics. A transmitter is configured to duplicate a packet and transmit the duplicated packets. The receiver is configured to receive the duplicated packets. The receiver is configured to transfer, to an upper layer in the receiver, a first packet ( 1401, 1403, 1405, 1408 ) that is a packet received earlier out of the duplicated packets. A transfer timing that is a timing with which the first packet ( 1401, 1403, 1405, 1408 ) is transferred to the upper layer includes at least one of: a reception timing of a second packet ( 1402, 1404, 1406, 1407 ) that is a packet received later than the first packet out of the duplicated packets; and a cyclical timing (Cycle time) corresponding to a transmission cycle of the duplicated packets.
1 . A user apparatus in a communication system, the communication system comprising:
a plurality of user apparatuses including the user apparatus, and configured to communicate with each other in a sidelink; and
a base station configured to wirelessly communicate with each of the user apparatuses,
wherein the user apparatus is configured to:
transmit, to another user apparatus of the plurality of user apparatuses, a request signaling for requesting a setting related to resources for unicast communication in the sidelink, the request signaling including first information on a priority;
receive, from the another user apparatus, second information on the setting related to resources for unicast communication;
perform received power measurement based on threshold set for each resource use; and
configure the resources for transmission by using the second information and excluding, based on the measurement, a first transmission resource and a retransmission resource from resource candidates for the unicast communication in an autonomous resource selection.
2 . The user apparatus according to claim 1 , wherein the resources are resources for data transmission.
3 . The user apparatus according to claim 2 , wherein the resources for data transmission include resources for a first transmission data and a retransmission data.
4 . The user apparatus according to claim 1 , wherein the resources are resources for channel state information (CSI) reporting.
5 . The user apparatus according to claim 1 , wherein the setting includes at least any of resource sensing, transmission resource selection, and transmission resource reservation.
6 . The user apparatus according to claim 1 , wherein the user apparatus transmits a control signal, a channel, or a signaling for starting connection establishment prior to the unicast communication.
7 . The user apparatus according to claim 1 , wherein the user apparatus decides, according to a transmission data type, whether or not to perform the setting related to the resources.
8 . The user apparatus according to claim 1 , wherein the user apparatus associates a data with an HARQ feedback resource.
9 . The user apparatus according to claim 1 , wherein the user apparatus evaluates a channel occupied ratio (CR) that indicates a ratio of used resources used for first transmission and retransmission.
10 . The user apparatus according to claim 1 , wherein the first information is a ProSe Per-Packet Priority (PPPP).
11 . A communication system comprising:
a plurality of user apparatuses including the user apparatus, and configured to communicate with each other in a sidelink; and
a base station configured to wirelessly communicate with each of the user apparatuses,
wherein user apparatus is configured to:
transmit, to another user apparatus of the plurality of user apparatuses, a request signaling for requesting a setting related to resources for unicast communication in the sidelink, the request signaling including first information on a priority;
receive, from the another user apparatus, second information on the setting related to resources for unicast communication;
perform received power measurement based on threshold set for each resource use; and
configure the resources for transmission by using the second information and excluding, based on the measurement, a first transmission resource and a retransmission resource from resource candidates for the unicast communication in an autonomous resource selection.