Methods, apparatus, systems, architectures and interfaces for channel state information reference signal for next generation wireless communication systems
Methods, apparatus, systems, architectures and interfaces for reference signal (RS) configuration, generation, and/or transmission in a transmitter/receiver. The method includes receiving information indicating any of at least first and second modes of operation for transmitting a discrete Fourier transform (DFT)-spread-orthogonal frequency division multiplexing (DFT-s-OFDM) symbol including a reference signal (RS), and transmitting the DFT-s-OFDM symbol including: (1) the RS and data tones, on condition that the information indicates the first mode; or (2) the RS and null tones, on condition that the information indicates the second mode, wherein the DFT-s-OFDM symbol is divided into a number of segments, each including a chunk of RS tones, and wherein any of a size or a location of the chunk is determined according to any of the first or second modes.
1. A method implemented in a wireless transmit/receive unit (WTRU) including a processor and a transceiver, the method comprising:
receiving information indicating one or more beam indices associated with a discrete Fourier transform (DFT)-spread-orthogonal frequency division multiplexing (DFT-s-OFDM) symbol including a reference signal (RS); and
transmitting the DFT-s-OFDM symbol, which includes a plurality of sub-symbols, using one or more transmit beams according to the information indicating the one or more beam indices, wherein a plurality of RS tones of the RS and null tones are included in the plurality of sub-symbols.
2. The method of claim 1 , wherein the null tones segment the plurality of RS tones in the plurality of sub-symbols,
wherein the transmitting the DFT-s-OFDM symbol includes transmitting all of the plurality of RS tones in the plurality of sub-symbols of the DFT-s-OFDM symbol using a single beam among the one or more beams, and wherein each of the plurality of sub-symbols includes a set of the RS tones.
3. The method of claim 1 , wherein the null tones segment the plurality of RS tones in the plurality of sub-symbols,
wherein the transmitting the DFT-s-OFDM symbol includes transmitting the plurality of RS tones in different ones of the plurality of sub-symbols of the DFT-s-OFDM symbol using different beams among the one or more beams, and
wherein each of the plurality of sub-symbols includes a set of the RS tones.
4. The method of claim 1 , wherein the RS comprise any of a phase tracking reference signal (PTRS) and a beam management reference signal,
wherein the RS tones are used for any of demodulation or signal measurement, and
wherein each sub-symbol comprises a set of one or more of the RS tones and one or more of the null tones.
5. The method of claim 4 , wherein the RS tones in at least one of the respective sub-symbols includes two or more consecutive RS tones included in the respective sub-symbol.
6. The method of claim 1 , further comprising:
determining a sequence for the RS tones according to any of: (1) WTRU specific parameters, or (2) associated beam information,
wherein the WTRU specific parameters include any of: a WTRU identifier (ID), a scrambling ID configured via a higher layer signaling, or a scheduling parameter.
7. The method of claim 1 , wherein a location of the plurality of RS tones within one of the plurality of sub-symbols is any of: predetermined, configured, or determined according to a scheduling parameter.
8. The method of claim 1 , further comprising:
determining the number of sub-symbols according to any of higher layer signaling, a WTRU capability, and/or a number of the one or more transmit beams; and
determining a location of the RS tones within at least one of the sub-symbols based on another location of other RS tones within another DFT-s-OFDM symbol used for data transmission.
9. The method of claim 1 , further comprising:
transmitting another DFT-s-OFDM symbol using the one or more transmit beams according to the information indicating the one or more beam indices in any of a same slot, or transmission time interval (TTI) as the DFT-s-OFDM symbol,
wherein a same transmission power is used to transmit each of the RS tones in the plurality of sub-symbols of the DFT-s-OFDM symbol.
10. The method of claim 9 , further comprising:
determining a location of the RS tones in the plurality of sub-symbols according to any of a WTRU specific parameter or a cell specific parameter,
wherein the WTRU specific parameter is any of a WTRU identifier (ID), a C-RNTI, or a scrambling ID configured via a WTRU specific higher layer signaling, and
wherein the cell specific parameter is a physical cell ID.
11. The method of claim 1 , wherein quasi-collocation (QCL) information is any of configured or indicated to be associated with any of the plurality of sub-symbols of the DFT-s-OFDM symbol.
12. A wireless transmit/receive unit (WTRU) comprising:
a processor and a transceiver which are configured to:
receive information indicating one or more beam indices associated with a discrete Fourier transform (DFT)-spread-orthogonal frequency division multiplexing (DFT-s-OFDM) symbol including a reference signal (RS); and
transmit the DFT-s-OFDM symbol, which includes a plurality of sub-symbols, using one or more transmit beams according to the information indicating the one or more beam indices, wherein a plurality of RS tones of the RS and null tones are included in the plurality of sub-symbols.
13. The WTRU of claim 12 , wherein the null tones segment the plurality of RS tones in the plurality of sub-symbols, and
wherein the processor and the transceiver are configured to:
transmit the DFT-s-OFDM symbol which includes to transmit all of the plurality of RS tones in the plurality of sub-symbols of the DFT-s-OFDM symbol using a single beam among the one or more beams, and
wherein, each of the plurality of sub-symbols includes a set of the RS tones.
14. The WTRU of claim 12 , wherein the null tones segment the plurality of RS tones in the plurality of sub-symbols,
wherein the transmitting the DFT-s-OFDM symbol includes transmitting the plurality of RS tones in different ones of the plurality of sub-symbols of the DFT-s-OFDM symbol using different beams among the one or more beams, and
wherein each of the plurality of sub-symbols includes a set of the RS tones.
15. The WTRU of claim 12 , wherein the RS comprise any of a phase tracking reference signal (PTRS) and a beam management reference signal,
wherein the RS tones are used for any of demodulation or signal measurement,
wherein each sub-symbol comprises a set of one or more of the RS tones and one or more of the null tones.
16. The WTRU of claim 12 , wherein the processor and the transceiver are configured to:
determine a sequence for the RS tones according to WTRU specific parameters,
wherein the WTRU specific parameters include any of: a WTRU identifier (ID), a scrambling ID configured via a higher layer signaling, or a scheduling parameter.
17. The WTRU of claim 12 , wherein the processor and the transceiver are configured to:
transmit another DFT-s-OFDM symbol using the one or more transmit beams according to the information indicating the one or more beam indices in any of a same slot or transmission time interval (TTI) as the DFT-s-OFDM symbol, and
wherein a same transmission power is used to transmit each of the RS tones in the plurality of sub-symbols of the DFT-s-OFDM symbol.
18. The device of claim 12 , wherein the processor and the transceiver are configured to:
determine a location of the RS tones in the plurality of sub-symbols according to any of a WTRU specific parameter or a cell specific parameter,
wherein the WTRU specific parameter is any of a WTRU identifier (ID), a C-RNTI, or a scrambling ID configured via a WTRU specific higher layer signaling, and
wherein the cell specific parameter is a physical cell ID.
19. The device of claim 12 , wherein quasi-collocation (QCL) information is any of configured or indicated to be associated with any of the plurality of sub-symbols of the DFT-s-OFDM symbol.
20. The WTRU of claim 15 , wherein the RS tones in at least one of the respective sub-symbols includes two or more consecutive RS tones.