User equipment (UE) and method of sidelink data communication in fifth generation (5G) new radio (NR) things networks

1. An apparatus of a network User Equipment (nUE), the apparatus comprising: a processor configured to cause the nUE to:

encode, for transmission during a subframe, a control channel that allocates the subframe as either a downlink subframe or an uplink subframe for a sidelink communication between the nUE and a wearable User Equipment (wUE);

when the control channel allocates the subframe as the downlink subframe:

encode, for transmission in a physical resource block (PRB) of channel resources comprising multiple PRBs, a transmitter resources acquisition and sounding (TAS) channel to the wUE to contend for access to the channel resources;

attempt to detect a receiver resources acquisition and sounding (RAS) channel from the wUE in the PRB; and

determine whether to transmit data to the wUE based at least partly on whether the RAS channel from the wUE is detected;

when the control channel allocates the subframe as the uplink subframe:

attempt to detect a TAS channel from the wUE in the PRB;

and

when the TAS channel from the wUE is detected in the PRB, encode a RAS channel for transmission to the wUE in the PRB;

wherein:

the control channel is transmitted in a control physical resource allocation (PRA) that includes one or more PRBs,

when the control channel allocates the subframe as the downlink subframe, the control PRA is based on the nUE and the control channel is scrambled by an identifier of the nUE, and

when the control channel allocates the subframe as the uplink subframe, the control PRA is based on the wUE and the control channel is scrambled by an identifier of the wUE.

2. The apparatus according to claim 1 , the processor further configured to, when the control channel allocates the subframe as the downlink subframe:

when the RAS channel is detected, transmit the data to the wUE in a physical resource allocation (PRA) of one or more PRBs, including the PRB used for transmission of the TAS channel; and

refrain from transmission of the data to the wUE when the RAS channel is not detected.

3. The apparatus according to claim 2 , wherein:

the RAS channel from the wUE indicates a modulation and coding scheme (MCS), and

the data is transmitted in accordance with the indicated MCS.

4. The apparatus according to claim 1 , wherein:

the TAS channel encoded by the nUE, the RAS channel encoded by the nUE, the TAS channel from the wUE, and the RAS channel from the wUE are scrambled by an identifier of the wUE.

5. The apparatus according to claim 1 , wherein: the channel

resources comprise multiple PRBs, and

the processor is further configured to, when the control channel allocates the subframe as the downlink subframe:

encode a plurality of TAS channels for per-PRB transmissions in a plurality of PRBs to contend for access to the plurality of PRBs;

attempt to detect RAS channels in the plurality of PRBs on a per-PRB basis; and

determine whether to transmit data based on the attempted detection of the RAS channels.

6. The apparatus according to claim 5 , wherein when the control channel allocates the subframe as the downlink subframe, the TAS channels are encoded for transmission to contend for access to the channel resources for multiple data transmissions to the wUE.

7. The apparatus according to claim 5 , wherein when the control channel allocates the subframe as the downlink subframe, the TAS channels are encoded for transmission to contend for access to the channel resources for at least one data transmission to each wUE of a plurality of wUEs.

8. The apparatus according to claim 5 , wherein:

the plurality of PRBs is a first plurality of PRBs,

the processor is further configured to, when the control channel allocates the subframe as the uplink subframe:

attempt to detect a TAS channel from the wUE in each PRB of a second plurality of PRBs; and

in each PRB of the second plurality on which the TAS channel from the wUE is successfully detected, encode a RAS channel for transmission in the PRB.

9. The apparatus according to claim 1 , wherein:

the control channel includes an uplink/downlink (UL/DL) indicator that indicates whether the subframe is allocated as the uplink subframe or the downlink subframe,

TAS channels by nUEs and/or wUEs include a new data indicator (NDI) that indicates whether a data transmission is a new data transmission or a retransmission, and

the RAS channel includes a modulation and coding scheme (MCS) and a downlink power headroom (PHR) measurement.

10. The apparatus according to claim 1 , wherein:

the subframe is included in a frame that comprises a plurality of subframes,

the processor is further configured to determine, on a per-subframe basis, whether the subframes of the plurality are to be used as either downlink subframes usable for transmission of downlink data from the nUE to the wUE or as uplink subframes usable for transmission of uplink data from the wUE to the nUE.

11. The apparatus according to claim 1 , wherein the subframe comprises:

a TAS portion allocated for per-PRB transmissions of TAS channels by nUEs and/or wUEs attempting to access the channel resources,

a RAS portion allocated for per-PRB transmissions of RAS channels in response to the TAS channels, and

a data portion allocated for transmissions of data based on receptions of the RAS channels.

12. The apparatus according to claim 1 , wherein:

the processor is further configured to determine a reference timing for the sidelink communication based on at least one of:

one or more signals exchanged with a base station in a network communication,

one or more signals received from another nUE, or

an internally generated reference timing, and

the subframe is aligned in accordance with the reference timing for the sidelink communication.

13. The apparatus according to claim 1 , wherein the nUE is arranged to operate in accordance with a Fifth Generation (5G) New Radio (NR) Things protocol.

14. The apparatus according to claim 1 , wherein the apparatus further includes a transceiver to transmit the control channel.

15. The apparatus according to claim 1 , wherein the processor includes a baseband processor to encode the control channel.

16. A non-transitory computer-readable storage medium that stores instructions for execution by one or more processors to perform operations for communication by a network User Equipment (nUE), the operations to configure the one or more processors to:

allocate subframes of a frame as downlink frames or uplink frames for a sidelink communication between the nUE and one or more wearable User Equipment (wUE), the allocation on a per-subframe basis;

during the subframes allocated as downlink subframes:

contend for access to channel resources for data transmissions, the channel resources comprising multiple physical resource blocks (PRBs), the contention based on per-PRB transmissions of transmitter resources acquisition and sounding (TAS) channels and per-PRB detections of receiver resources acquisition and sounding (RAS) channels responsive to the TAS channels; and

during the subframes allocated as uplink subframes:

monitor one or more PRBs for TAS channels from one or more wUEs contending for access;

when a first TAS channel from a first wUE is not detected in the PRB, refrain from encoding of the RAS channel for transmission to the first wUE;

when a second TAS channel from a second wUE is detected in the PRB, decode data received from the second wUE during the PRB; and

encode RAS channels for per-PRB transmission in response to detected TAS channels.

17. The non-transitory computer-readable storage medium according to claim 16 , wherein the subframes are allocated as downlink frames or uplink frames based at least partly on sizes of downlink data to be transmitted to the one or more wUEs and/or sizes of uplink data to be received from the one or more wUEs.

18. The non-transitory computer-readable storage medium according to claim 16 , wherein the nUE is arranged to operate in accordance with a Fifth Generation (5G) New Radio (NR) Things protocol.

19. An apparatus of a wearable User Equipment (wUE), the apparatus comprising:

a processor configured to cause the wUE to:

decode a control channel received from a network User Equipment (nUE) during a subframe, wherein the control channel allocates the subframe as either a downlink subframe or an uplink subframe for a sidelink communication between the nUE and the wUE;

when the control channel allocates the subframe as the uplink subframe:

encode, for transmission in a physical resource block (PRB) of channel resources that comprises multiple PRBs, a transmitter resources acquisition and sounding (TAS) channel to the nUE to contend for access to the PRB;

attempt to detect a receiver resources acquisition and sounding (RAS) channel from the nUE in the PRB; and

determine, based at least partly on whether the RAS channel from the nUE is detected, whether to transmit data to the nUE in a physical resource allocation (PRA) of one or more PRBs, including the PRB used for the TAS channel;

when the control channel allocates the subframe as the downlink subframe:

attempt to detect a TAS channel from the nUE in the PRB; and

when the TAS channel from the nUE is detected in the PRB, encode a RAS channel for transmission to the nUE in the PRB;

wherein:

the control channel is transmitted in a control physical resource allocation (PRA) that includes one or more PRBs,

when the control channel allocates the subframe as the downlink subframe, the control PRA is based on the nUE and the control channel is scrambled by an identifier of the nUE, and

when the control channel allocates the subframe as the uplink subframe, the control PRA is based on the wUE and the control channel is scrambled by an identifier of the wUE.

20. The apparatus according to claim 19 , wherein the wUE is arranged to operate in accordance with a Fifth Generation (5G) New Radio (NR) Things protocol.