MULTI-LENGTH ZT DFT-S-OFDM TRANSMISSION

• US 20180316537A1
• Filed: 11/02/2016
• Published: 11/01/2018
• Est. Priority Date: 11/04/2015
• Status: Active Grant

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: IDAC Holdings, Inc. (InterDigital, Inc.)
• Inventors: Haghighat, Afshin, Bala, Erdem, Kini, Ananth, Sahin, Alphan
• Granted Patent: US 10,644,919 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 1/38 Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
• CPC Class Codes: H04J 11/00 Orthogonal multiplex systems, e.g. using WALSH codesH04J13/00 takes precedence
• CPC Class Codes: H04L 27/2636 with FFT or DFT modulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] transmitter or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]
• CPC Class Codes: H04L 5/0039 Frequency-contiguous, i.e. with no allocation of frequencies for one user or terminal between the frequencies allocated to another
• CPC Class Codes: H04L 5/0073 Allocation arrangements that take into account other cell interferences for intercell interference mitigation or co-ordination in orthogonal multiplex systems H04J11/005

Abstract

Techniques may be used to generate a multi-length Zero Tail (ZT) Discrete Fourier Transform-spread Orthogonal Frequency Domain Modulation (DFT-s-OFDM) signal for transmission. A selected allocation of frequency resources may include a plurality of subbands. Subbands may be assigned to wireless transmit/receive units (WTRUs) (i.e., users), and zero head length and zero tail length may be assigned to each of the assigned subbands according to a pattern to combat inter-symbol interference (ISI). The ZT DFT-s OFDM signal may generated for transmission over the assigned subbands in accordance with the assigned zero head length and the assigned zero tail length.

Claims

1. A method performed by a network device, the method comprising:

selecting, by the network device, an allocation of frequency resources for transmission, wherein the frequency resources include a plurality of subbands;

assigning, by the network device, one or more of the plurality of subbands to each of a plurality of wireless transmit/receive units (WTRUs);

assigning, by the network device, a zero head length and a zero tail length to each of the assigned one or more of the plurality of subbands based on one or more patterns;

generating, by the network device, a multi-length zero tail (ZT) discrete Fourier transform-spread orthogonal frequency division multiplexing (DFT-s-OFDM) signal for the assigned one or more of the plurality of subbands with a zero head based on the assigned zero head length and a zero tail based on the assigned zero tail length; and

transmitting, by the network device, the multi-length ZT DFT-s OFDM signal.

2. The method of claim 1, wherein the one or more patterns include increasing or decreasing the zero head length and the zero tail length between adjacent subbands.

3. The method of claim 1, wherein:

the assigning of the one or more of the plurality of subbands to each of the plurality of WTRUs includes assigning adjacent subbands to WTRUs with a same channel delay profile.

5. The method of claim 1, wherein:

the assigning the zero head length and the zero tail length to each of the assigned one or more of the plurality of subbands is repeated at each time slot, within an allocated time period, such that the assigned zero head length and the assigned zero tail length to a first assigned subband in a first time slot is different than in a second time slot immediately following the first time slot.

6. The method of claim 1, further comprising:

applying, by the network device, a pre-known sequence with a correlation property to a first generated ZT DFT-s OFDM signal for transmission so that a receiving WTRU may determine the zero head length and the zero tail length.

8. The method of claim 1, wherein:

the generating the multi-length ZT DFT-s OFDM signal includes inserting zeros into a time domain to generate a zeroed-out portion of the multi-length ZT DFT-s OFDM signal.

9. The method of claim 8 further comprising:

inserting, by the network device, ultra-reliable low-latency data into the zeroed-out portion of the multi-length ZT DFT-s OFDM signal.

10. The method of claim 8, wherein one or more measurements are performed during the zeroed-out portion of the multi-length ZT DFT-s OFDM signal.

4. (canceled)

7. (canceled)

11. A network device comprising:

a transceiver coupled to a processor and at least one antenna;

the processor configured to select an allocation of frequency resources for transmission, wherein the frequency resources include a plurality of subbands;

the processor configured to assign one or more of the plurality of subbands to each of a plurality of wireless transmit/receive units (WTRUs);

the processor configured to assign a zero head length and a zero tail length to each of the assigned one or more of the plurality of subbands based on one or more patterns;

the processor configured to generate a multi-length zero tail (ZT) discrete Fourier transform-spread orthogonal frequency division multiplexing (DFT-s-OFDM) signal for the assigned one or more of the plurality of subbands with a zero head based on the assigned zero head length and a zero tail based on the assigned zero tail length; and

the transceiver configured to transmit the multi-length ZT DFT-s OFDM signal.

12. The network device of claim 11, wherein the one or more patterns include increasing or decreasing the zero head length and the zero tail length between adjacent subbands.

13. The network device of claim 11, wherein:

the processor is configured to assign the one or more of the plurality of subbands to each of the plurality of WTRUs includes assigning adjacent subbands to WTRUs with a same channel delay profile.

15. The network device of claim 11, wherein:

the processor is configured to assign the zero head length and the zero tail length to each of the assigned one or more of the plurality of subbands is repeated at each time slot, within an allocated time period, such that the assigned zero head length and the assigned zero tail length to a first assigned subband in a first time slot is different than in a second time slot immediately following the first time slot.

16. The network device of claim 11, wherein:

the processor is further configured to apply a pre-known sequence with a correlation property to a first generated ZT DFT-s OFDM signal for transmission so that a receiving WTRU may determine the zero head length and the zero tail length.

18. The network device of claim 11, wherein:

the processor is configured to generate the multi-length ZT DFT-s OFDM signal by inserting zeros into a time domain to generate a zeroed-out portion of the multi-length ZT DFT-s OFDM signal.

19. The network device of claim 18, wherein:

the processor is further configured to insert ultra-reliable low-latency data into the zeroed-out portion of the multi-length ZT DFT-s OFDM signal.

20. The network device of claim 18, wherein one or more measurements are performed during the zeroed-out portion of the multi-length ZT DFT-s OFDM signal.

14. (canceled)

17. (canceled)

21. A wireless transmit/receive unit (WTRU) comprising:

a transceiver coupled to a processor and at least one antenna;

the transceiver configured to receive a multi-length zero tail (ZT) discrete Fourier transform-spread orthogonal frequency division multiplexing (DFT-s-OFDM) signal; and

wherein the multi-length DFT-s-OFDM signal is composed of one or more of a plurality of subbands assigned to the WTRU and is composed of a zero head and a zero tail for each of the assigned one or more of the plurality of subbands based on one or more patterns.

22. The WTRU of claim 21, wherein the one or more patterns include increasing or decreasing the length between adjacent subbands.