Channel raster design in wireless communications

1. A method for wireless communications by a user equipment (UE), comprising:

determining an uplink channel raster for an uplink channel of a first system;

determining to shift, with respect to the uplink channel raster, an uplink transmission over the uplink channel by an offset in frequency, wherein the shift of the uplink transmission is based at least in part on tones of uplink carriers of the first system not being aligned with tones of uplink carriers of a second system; and

transmitting the shifted uplink transmission, wherein the shifted uplink transmission aligns in frequency with a second uplink channel of the second system.

2. The method of claim 1 , wherein the offset in frequency is 7.5 kilohertz.

3. The method of claim 1 , wherein the first system is new radio (NR) and the second system is long term evolution (LTE).

4. The method of claim 1 , further comprising:

receiving, from a base station, a parameter indicating to shift the uplink transmission by the offset in frequency, wherein the shift of the uplink transmission is based at least in part on receiving the parameter.

5. The method of claim 4 , wherein receiving the parameter includes receiving, from the base station, the parameter in radio resource control (RRC) signaling.

6. The method of claim 5 , wherein receiving the parameter is based on indicating a capability to communicate using at least the first system.

7. The method of claim 1 , wherein the offset in frequency is in a range of 7 to 8 kilohertz.

8. The method of claim 1 , further comprising:

identifying a downlink channel raster for a downlink channel over which to receive downlink communications from a base station,

wherein the uplink channel raster is of a different value than the downlink channel raster.

9. The method of claim 1 , further comprising:

determining an uplink frequency for the uplink channel based on one or more of the offset, the uplink channel raster, and an uplink channel number, and

wherein transmitting the shifted uplink transmission includes transmitting the shifted uplink transmission over the uplink frequency.

10. The method of claim 9 , further comprising:

receiving, from a base station and in broadcasted system information, along with a random access channel configuration, or in radio resource control (RRC) signaling, the uplink channel number.

11. The method of claim 1 , wherein transmitting the shifted uplink transmission includes:

transmitting uplink control signaling over the uplink channel, and

transmitting uplink data over a third uplink channel of the first system.

12. The method of claim 11 , wherein the first uplink channel overlaps in frequency with the second system, and wherein the third uplink channel does not overlap in frequency with the second system.

13. A method for wireless communications by a user equipment (UE), comprising:

determining an uplink channel raster for an uplink channel of a first system;

determining to shift, with respect to the uplink channel raster, an uplink transmission over the uplink channel by an offset in frequency, wherein the offset in frequency is less than a subcarrier spacing associated with a second system; and

transmitting the shifted uplink transmission, wherein the shifted uplink transmission aligns in frequency with a second uplink channel of the second system.

14. The method of claim 13 , wherein the offset in frequency is 7.5 kilohertz.

15. The method of claim 13 , wherein the first system is new radio (NR) and the second system is long term evolution (LTE).

16. The method of claim 13 , further comprising receiving, from a base station, a parameter indicating to shift the uplink transmission by the offset in frequency, wherein the shift of the uplink transmission is based at least in part on receiving the parameter.

17. The method of claim 16 , wherein receiving the parameter includes receiving, from the base station, the parameter in radio resource control (RRC) signaling.

18. An apparatus for wireless communication, comprising:

a transceiver;

a memory configured to store instructions; and

one or more processors communicatively coupled with the transceiver and the memory, wherein the one or more processors are configured to cause the apparatus to:

determine an uplink channel raster for an uplink channel of a first system;

determine to shift, with respect to the uplink channel raster, an uplink transmission over the uplink channel by an offset in frequency, wherein the shift of the uplink transmission is based at least in part on tones of uplink carriers of the first system not being aligned with tones of uplink carriers of a second system; and

transmit the shifted uplink transmission, wherein the shifted uplink transmission aligns in frequency with a second uplink channel of the second system.

19. The apparatus of claim 18 , wherein the offset in frequency is 7.5 kilohertz.

20. The apparatus of claim 18 , wherein the first system is new radio (NR) and the second system is long term evolution (LTE).

21. The apparatus of claim 18 , wherein the one or more processors are further configured to cause the apparatus to receive, from a base station, a parameter indicating to shift the uplink transmission by the offset in frequency, wherein the one or more processors are configured to cause the apparatus to shift the uplink transmission based at least in part on receiving the parameter.

22. The apparatus of claim 21 , wherein the one or more processors are configured to cause the apparatus to receive the parameter in radio resource control (RRC) signaling from the base station.

23. The apparatus of claim 21 , wherein the one or more processors are configured to cause the apparatus to receive the parameter based on indicating a capability to communicate using at least the first system.

24. The apparatus of claim 18 , wherein the offset in frequency in a range of 7 to 8 kilohertz.

25. The apparatus of claim 18 , wherein the one or more processors are further configured to cause the apparatus to:

determine an uplink frequency for the uplink channel based on one or more of the offset, the uplink channel raster, and an uplink channel number, and

wherein the one or more processors are configured to cause the apparatus to transmit the shifted uplink transmission over the uplink frequency.

26. The apparatus of claim 25 , wherein the one or more processors are further configured to cause the apparatus to:

receive, from a base station and in broadcasted system information, along with a random access channel configuration, or in radio resource control (RRC) signaling, the uplink channel number.

27. The apparatus of claim 18 , wherein the one or more processors are configured to cause the apparatus to transmit the shifted uplink transmission as uplink control signaling over the uplink channel, and transmit uplink data over a third uplink channel of the first system.

28. The apparatus of claim 27 , wherein the first uplink channel overlaps in frequency with the second system, and wherein the third uplink channel does not overlap in frequency with the second system.

29. An apparatus for wireless communication, comprising:

a transceiver;

a memory configured to store instructions; and

one or more processors communicatively coupled with the transceiver and the memory, wherein the one or more processors are configured to cause the apparatus to:

determine an uplink channel raster for an uplink channel of a first system;

determine to shift, with respect to the uplink channel raster, an uplink transmission over the uplink channel by an offset in frequency, wherein the offset in frequency is less than a subcarrier spacing associated with a second system; and

transmit the shifted uplink transmission, wherein the shifted uplink transmission aligns in frequency with a second uplink channel of the second system.

30. The apparatus of claim 29 , wherein the offset in frequency is 7.5 kilohertz.