Demodulation reference signal and phase rotation for sub-physical resource block allocation with two tone modulation
Methods, apparatuses, and computer program products for wireless communication are provided. A user equipment (UE) may be configured to determine a phase rotation for a symbol based at least in part on a tone index. The UE may be configured to apply the phase rotation to the received symbol, and transmit the uplink symbol. Numerous other aspects are provided.
1. A method of wireless communication, comprising:
receiving, by a base station, a symbol in an uplink communication, wherein the uplink communication uses a two-tone modulation scheme and is in accordance with a resource allocation at sub physical resource block granularity,
wherein the resource allocation includes resource allocations of three adjacent subcarriers where only two subcarriers of the three adjacent subcarriers are used for transmitting the uplink communication;
determining, by the base station, a phase rotation for the symbol in the uplink communication, wherein the phase rotation is determined based at least in part on a reference tone index associated with the resource allocation,
wherein the reference tone index is the same for each symbol of the uplink communication; and
applying, by the base station, the phase rotation to the symbol.
2. The method of claim 1 , wherein the two-tone modulation scheme uses π/2 binary phase shift keying (BPSK) modulation.
3. The method of claim 1 , wherein the reference tone index matches a tone index of one of three tones associated with the resource allocation.
4. The method of claim 1 , wherein the reference tone index is based at least in part on two tones associated with the resource allocation.
5. The method of claim 4 , wherein the reference tone index is based at least in part on a midpoint between the two tones associated with the resource allocation.
6. The method of claim 1 , wherein the phase rotation is further determined based on a tone index of a tone in which the symbol is received.
7. The method of claim 6 , wherein the phase rotation is reset at a start of a subframe or a start of a slot.
8. The method of claim 1 , wherein the reference tone index is based at least in part on a midpoint between two adjacent tone indexes associated with the resource allocation.
9. A method of wireless communication, comprising:
determining, by a user equipment, a phase rotation for a symbol associated with an uplink communication,
wherein the uplink communication is to use a two-tone modulation scheme and is in accordance with a resource allocation at sub physical resource block granularity,
wherein the resource allocation includes resource allocations of three adjacent subcarriers where only two subcarriers of the three adjacent subcarriers are used for transmitting the uplink communication,
wherein the phase rotation is determined based at least in part on a reference tone index associated with the resource allocation, and
wherein the reference tone index is the same for each symbol of the uplink communication;
applying, by the user equipment, the phase rotation to the symbol associated with the uplink communication; and
transmitting, by the user equipment, the symbol associated with the uplink communication.
10. The method of claim 9 , wherein the two-tone modulation scheme uses π/2 binary phase shift keying (BPSK) modulation.
11. The method of claim 10 , wherein the reference tone index matches a tone index of one of three tones associated with the resource allocation.
12. The method of claim 10 , wherein the reference tone index is based at least in part on two tones associated with the resource allocation.
13. The method of claim 12 , wherein the reference tone index is based at least in part on a midpoint between the two tones associated with the resource allocation.
14. The method of claim 9 , wherein the phase rotation is further determined based on a tone index of a tone in which the symbol is to be transmitted.
15. The method of claim 14 , wherein the phase rotation is reset at a start of a subframe or a start of a slot.
16. The method of claim 9 , wherein the reference tone index is based at least in part on a midpoint between two adjacent tone indexes associated with the resource allocation.
17. A wireless communication device for wireless communication, comprising:
memory; and
one or more processors coupled to the memory, the memory and the one or more processors configured to:
determine a phase rotation for a symbol associated with an uplink communication,
wherein the uplink communication uses a two-tone modulation scheme and is in accordance with a resource allocation at sub physical resource block granularity,
wherein the resource allocation includes resource allocations of three adjacent subcarriers where only two subcarriers of the three adjacent subcarriers are used for transmitting the uplink communication,
wherein the phase rotation is determined based at least in part on a reference tone index associated with the resource allocation, and
wherein the reference tone index is the same for each symbol of the uplink communication;
apply the phase rotation to the symbol associated with the uplink communication; and
transmit the symbol associated with the uplink communication.
18. The wireless communication device of claim 17 , wherein the two-tone modulation scheme uses π/2 binary phase shift keying (BPSK) modulation.
19. The wireless communication device of claim 17 , wherein the reference tone index matches a tone index of one of three tones associated with the resource allocation.
20. The wireless communication device of claim 17 , wherein the reference tone index is based at least in part on two tones associated with the resource allocation.
21. The wireless communication device of claim 20 , wherein the reference tone index is based at least in part on a midpoint between the two tones associated with the resource allocation.
22. The wireless communication device of claim 17 , wherein the phase rotation is further determined based on a tone index of a tone in which the symbol is communicated.
23. The wireless communication device of claim 22 , wherein the phase rotation is reset at a start of a subframe or a start of a slot.
24. A wireless communication device for wireless communication, comprising:
memory; and
one or more processors coupled to the memory, the memory and the one or more processors configured to:
receive a symbol in an uplink communication, wherein the uplink communication uses a two-tone modulation scheme and is in accordance with a resource allocation at sub physical resource block granularity,
wherein the resource allocation includes resource allocations of three adjacent subcarriers where only two subcarriers of the three adjacent subcarriers are used for transmitting the uplink communication;
determine a phase rotation for the symbol in the uplink communication, wherein the phase rotation is determined based at least in part on a reference tone index associated with the resource allocation,
wherein the reference tone index is the same for each symbol of the uplink communication; and
apply the phase rotation to the symbol.
25. The wireless communication device of claim 24 , wherein the two-tone modulation scheme uses π/2 binary phase shift keying (BPSK) modulation.
26. The wireless communication device of claim 24 , wherein the reference tone index matches a tone index of one of three tones associated with the resource allocation.
27. The wireless communication device of claim 24 , wherein the reference tone index is based at least in part on two tones associated with the resource allocation.
28. The wireless communication device of claim 27 , wherein the reference tone index is based at least in part on a midpoint between the two tones associated with the resource allocation.
29. The wireless communication device of claim 24 , wherein the phase rotation is further determined based on a tone index of a tone in which the symbol is received.
30. The wireless communication device of claim 29 , wherein the phase rotation is reset at a start of a subframe or a start of a slot.