Flexible waveform synthesis in NR-SS

1. A method of wireless communication, comprising:

constructing, by a transmitter, an M×N grid to model a resource element (RE) map of transmission resources available to the transmitter within a shared communication channel, wherein M corresponds to a number of symbols for a scheduled physical signal and N corresponds to a number of tones of a transmission bandwidth for the transmitter operating on the shared communication channel;

mapping, by the transmitter, the M×N grid to the RE map;

puncturing, by the transmitter, one or more REs of the RE map associated with one or more unavailable subbands unavailable for transmission by the transmitter in the transmission resources; and

transmitting, by the transmitter, a transmission according to unpunctured REs of the RE map.

2. The method of claim 1 , further including:

performing, by the transmitter, a listen before talk (LBT) procedure to obtain access to the shared communication channel;

determining, by the transmitter, the number of symbols available for the scheduled physical signal as a number of remaining symbols between a detected success of the LBT procedure and an end boundary of a current transmission opportunity.

3. The method of claim 1 , further including:

determining, by the transmitter, a portion of a system bandwidth associated with the scheduled physical signal; and

identifying, by the transmitter, the number of tones based on the determined portion of the system bandwidth.

4. The method of claim 1 , wherein the constructing the M×N grid includes:

generating, by the transmitter, a constant amplitude zero autocorrelation (CAZAC) sequence having a M length;

generating, by the transmitter, K chirp sequences each having a N/K length, wherein K; and

concatenating, by the transmitter, the CAZAC sequence and the K chirp sequences into the M×N grid.

5. The method of claim 4 , further including identifying, by the transmitter, the one or more subbands belonging to the shared or unlicensed spectrum unavailable for transmission in the time-frequency resources shared between the transmitter and other users.

6. The method of claim 5 , further including:

selecting, by the transmitter, a scrambling sequence from a plurality of available scrambling sequences, wherein the selection is based on the one or more unavailable subbands of the shared or unlicensed spectrum identified by the transmitter.

7. The method of claim 6 , wherein the generating the CAZAC sequence further includes:

selecting, by the transmitter, a root index and cyclic shift of the CAZAC sequence from a plurality of pre-configured root indices and a plurality of pre-configured cyclic shifts, wherein the selection is based on the one or more unavailable subbands identified by the transmitter.

8. The method of claim 1 , further including:

signaling, by the transmitter, the one or more unavailable subbands to a receiver operating on shared or unlicensed spectrum including an opportunistic use of the one or more unavailable subbands.

9. The method of claim 1 , wherein the transmission includes one of:

a discovery reference signal;

a synchronization signal;

an acknowledgement signal;

a short physical uplink control channel;

a scheduling request; or

a spreading sequence.

10. An apparatus configured for wireless communication, comprising:

at least one processor; and

a memory coupled to the at least one processor,

wherein the at least one processor is configured:

to constructing, by a transmitter, an M×N grid to model a resource element (RE) map of transmission resources available to the transmitter within a shared communication channel, wherein M corresponds to a number of symbols for a scheduled physical signal and N corresponds to a number of tones of a transmission bandwidth for the transmitter operating on the shared communication channel;

to map, by the transmitter, the M×N grid to the RE map;

to puncture, by the transmitter, one or more REs of the RE map associated with one or more unavailable subbands unavailable for transmission by the transmitter in the transmission resources; and

to transmit, by the transmitter, a transmission according to unpunctured REs of the RE map.

11. The apparatus of claim 10 , further including configuration of the at least one processor:

to perform, by the transmitter, a listen before talk (LBT) procedure to obtain access to the shared communication channel;

to determine, by the transmitter, the number of symbols available for the scheduled physical signal as a number of remaining symbols between a detected success of the LBT procedure and an end boundary of a current transmission opportunity.

12. The apparatus of claim 10 , further including configuration of the at least one processor:

to determine, by the transmitter, a portion of a system bandwidth associated with the scheduled physical signal; and

to identify, by the transmitter, the number of tones based on the determined portion of the system bandwidth.

13. The apparatus of claim 10 , wherein the configuration of the at least one processor to construct the M×N grid includes configuration of the at least one processor:

to generate, by the transmitter, a constant amplitude zero autocorrelation (CAZAC) sequence having a M length;

to generate, by the transmitter, K chirp sequences each having a N/K length, wherein K; and

to concatenate, by the transmitter, the CAZAC sequence and the K chirp sequences into the M×N grid.

14. The apparatus of claim 13 , further including configuration of the at least one processor to identify, by the transmitter, the one or more subbands belonging to the shared or unlicensed spectrum unavailable for transmission in the time-frequency resources shared between the transmitter and other users.

15. The apparatus of claim 14 , further including configuration of the at least one processor to select, by the transmitter, a scrambling sequence from a plurality of available scrambling sequences, wherein the selection is based on the one or more unavailable subbands of the shared or unlicensed spectrum identified by the transmitter.

16. The apparatus of claim 15 , wherein the configuration of the at least one processor to generate the CAZAC sequence further includes configuration of the at least one processor to select, by the transmitter, a root index and cyclic shift of the CAZAC sequence from a plurality of pre-configured root indices and a plurality of pre-configured cyclic shifts, wherein the selection is based on the one or more unavailable subbands identified by the transmitter.

17. The apparatus of claim 10 , further including configuration of the at least one processor to signal, by the transmitter, the one or more unavailable subbands to a receiver operating on shared or unlicensed spectrum including an opportunistic use of the one or more unavailable subbands.

18. The apparatus of claim 10 , wherein the transmission includes one of:

a discovery reference signal;

a synchronization signal;

an acknowledgement signal;

a short physical uplink control channel;

a scheduling request; or

a spreading sequence.