Methods, architectures, apparatuses and systems for performing discontinuous reception on sidelink
The disclosure pertains to methods and apparatus using V2X enhancements to perform discontinuous reception. In an embodiment, a method implemented by a first WTRU, for a device-to-device (D2D) communication between the first WTRU and a second WTRU, the method may include any of comprising receiving, from the second WTRU, D2D control information comprising: (1) first information indicating one or more first transmission resources reserved for transmission of the D2D communication and (2) second information indicating if at least one second transmission resource is reserved for retransmission of the D2D communication; determining a sleeping period for the first WTRU that ends prior to a reception time of the retransmission of the D2D communication, wherein the sleeping period is based on the second information; and receiving the retransmission of the D2D communication, after an end of the determined sleeping period.
1 . A method implemented by a first wireless transmit/receive unit (WTRU), for a sidelink between the first WTRU and a second WTRU, the method comprising:
transmitting, to the second WTRU, sidelink control information comprising: (1) first information indicating at least a first transmission resource reserved for an initial transmission and (2) second information indicating if at least one second transmission resource is reserved for a sidelink retransmission of the initial transmission; and
determining an active time of the second WTRU based on a hybrid automatic repeat request (HARQ) round trip time (RTT) timer configured for the second WTRU, wherein:
the HARQ RTT timer has different durations depending on whether HARQ feedback is enabled or disabled; and
the HARQ RTT timer has different starting times depending on whether or not the second information indicates that at least one second transmission resource is reserved for the sidelink retransmission.
2 . The method of claim 1 , further comprising: receiving network configuration information indicating the different durations.
3 . The method of claim 1 , wherein, on condition that the HARQ feedback is enabled, the HARQ RTT timer starts in a time slot that follows a reception of the HARQ feedback.
4 . The method of claim 1 , wherein on condition that the HARQ feedback is disabled, and on condition that the second information indicates that at least one second transmission resource is reserved for the sidelink retransmission, the HARQ RTT timer starts in a time slot that follows the at least first transmission resource.
5 . The method of claim 1 , wherein on condition that the HARQ feedback is disabled, and on condition that the second information indicates that no second transmission resource is reserved for the sidelink retransmission, the HARQ RTT timer starts in a time slot that follows a resource reserved for a transmission of the HARQ feedback.
6 . The method of claim 1 , wherein the HARQ RTT timer is started at a predetermined time instance, at a first time instance indicated in the sidelink control information, or at a second time instance based on a sidelink cast type.
7 . A first wireless transmit/receive unit (WTRU), for a sidelink between the first WTRU and a second WTRU, the first WTRU comprising circuitry, including a transmitter, a receiver, a processor, and memory, configured to:
transmit, to the second WTRU, sidelink control information comprising: (1) first information indicating at least a first transmission resource reserved for an initial transmission and (2) second information indicating if at least one second transmission resource is reserved for a sidelink retransmission of the initial transmission; and
determine an active time of the second WTRU based on a hybrid automatic repeat request (HARQ) round trip time (RTT) timer configured for the second WTRU, wherein:
the HARQ RTT timer has different durations depending on whether HARQ feedback is enabled or disabled; and
the HARQ RTT timer has different starting times depending on whether or not the second information indicates that at least one second transmission resource is reserved for the sidelink retransmission.
8 . The first WTRU of claim 7 , further configured to receive network configuration information indicating the different durations.
9 . The first WTRU of claim 7 , wherein, on condition that the HARQ feedback is enabled, the HARQ RTT timer starts in a time slot that follows a reception of the HARQ feedback.
10 . The first WTRU of claim 7 , wherein on condition that the HARQ feedback is disabled and on condition that the second information indicates that at least one second transmission resource is reserved for the sidelink retransmission, the HARQ RTT timer starts in a time slot that follows the at least first transmission resource.
11 . The first WTRU of claim 7 , wherein on condition that the HARQ feedback is disabled and on condition that the second information indicates that no second transmission resource is reserved for the sidelink retransmission, the HARQ RTT timer starts in a time slot that follows a resource reserved for a transmission of the HARQ feedback.
12 . The first WTRU of claim 7 , wherein the HARQ RTT timer is started at a predetermined time instance, at a first time instance indicated in the sidelink control information, or at a second time instance based on a sidelink cast type.