STAGGERED PILOT PLACEMENT

• US 20170180104A1
• Filed: 09/15/2016
• Published: 06/22/2017
• Est. Priority Date: 12/18/2015
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: JI, Tingfang, PARK, Seyong, ZENG, Wei, JIANG, Jing, SORIAGA, Joseph Binamira
• Granted Patent: US 10,461,891 B2
• Time in Patent Office: Days
• CPC Class Codes: H04J 11/004 using regenerative subtractive interference cancellation
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0062 Avoidance of ingress interference, e.g. ham radio channels
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be configured to receive a plurality of combined signals. Each combined signal may be on a tone of a plurality of tones. The apparatus may be configured to determine a first pilot signal on a first tone of the plurality of tones. The apparatus may be configured to generate an interference-reduced signal for the first tone by canceling the determined first pilot signal from a first combined signal on the first tone.

Claims

1. An apparatus for wireless communication, comprising:

a processing system configured to;

receive a plurality of combined signals, each combined signal being on a tone of a plurality of tones, each combined signal comprising a first symbol of a first plurality of symbols from a first user equipment (UE) and a second symbol of a second plurality of symbols from a second UE, the first plurality of symbols including at least one first pilot symbol and at least one first data symbol, the second plurality of symbols including at least one second pilot symbol and at least one second data symbol, each of the at least one first pilot symbol being on a tone that carries one of the at least one second data symbol;

determine a first pilot signal on a first tone of the plurality of tones, the first tone carrying a respective one of the at least one first pilot symbol and a respective one of the at least one second data symbol, the first pilot signal being determined based on a channel element associated with the first tone and the respective one of the at least one first pilot symbol on the first tone; and

generate an interference-reduced signal for the first tone by canceling the determined first pilot signal from a first combined signal on the first tone.

2. The apparatus of claim 1, wherein the processing system is further configured to:

determine a second pilot signal on a second tone of the plurality of tones, the second tone carrying a respective one of the at least one second pilot symbol and a respective one of the at least one first data symbol, the second pilot signal being determined based on a second channel element associated with the second tone and the respective one of the at least one second pilot symbol on the second tone; and

generate a second interference-reduced signal for the second tone by canceling the determined second pilot signal from a second combined signal on the second tone.

3. The apparatus of claim 1, wherein a first set of periodic pilot signals from the first UE and a second set of periodic pilot signals from the second UE are shifted by a cyclic shift.

4. The apparatus of claim 1, wherein the processing system is further configured to provide a cyclic shift to the first UE.

5. The apparatus of claim 1, wherein the processing system is configured to de-interleave the plurality of combined signals to determine a first set of pilot signals from the first UE, first and second code blocks from the first UE, a second set of pilot signals from the second UE, and third and fourth code blocks from the second UE.

6. The apparatus of claim 5, wherein the first set of pilot signals corresponds to a first number tones, the first number tones being equal to half a second number of tones in the third code block.

7. The apparatus of claim 5, wherein the first set of pilot signals from the first UE overlaps with the third code block from the second UE, and the second set of pilot signals from the second UE overlaps with the second code block from the first UE.

8. The apparatus of claim 5, wherein the processing system is further configured to perform successive decoding after de-interleaving the plurality of combined signals.

9. The apparatus of claim 8, wherein the processing system is configured to perform successive decoding by:

decoding the third code block by canceling the first set of pilot signals from the third code block;

decoding the first code block by canceling the third code block from the first code block;

decoding the fourth code block by canceling the first code block from the fourth code block; and

decoding the second code block by canceling the fourth code block from the second code block.

10. An apparatus for wireless communication, comprising:

a processing system configured to;

map, at a first user equipment (UE), a first set of pilot symbols and a first set of data symbols to a plurality of tones, each pilot symbol in the first set of pilot symbols being mapped on a tone that is used by a second UE to carry a data symbol; and

provide the mapped first set of pilot symbols and the mapped first set of data symbols for transmission over the plurality of tones.

11. The apparatus of claim 10, wherein a data symbol in the first set of data symbols is mapped on a tone that is used by the second UE to carry a pilot symbol.

12. The apparatus of claim 10, wherein the first set of pilot symbols are transmitted on tones shifted by a cyclic shift from a second set of pilot symbols that is concurrently transmitted by the second UE.

13. The apparatus of claim 12, wherein the processing system is further configured to receive the cyclic shift for staggering the first set of pilot symbols from a base station.

14. The apparatus of claim 12, wherein the cyclic shift for staggering the first set of pilot symbols is randomly selected from a set of cyclic shift values based on an identifier associated with the first UE.

15. The apparatus of claim 10, wherein the first set of data symbols is associated with a same code block.

16. A method for wireless communication, comprising:

receiving a plurality of combined signals, each combined signal being on a tone of a plurality of tones, each combined signal comprising a first symbol of a first plurality of symbols from a first user equipment (UE) and a second symbol of a second plurality of symbols from a second UE, the first plurality of symbols including at least one first pilot symbol and at least one first data symbol, the second plurality of symbols including at least one second pilot symbol and at least one second data symbol, each of the at least one first pilot symbol being on a tone that carries one of the at least one second data symbol;

determining a first pilot signal on a first tone of the plurality of tones, the first tone carrying a respective one of the at least one first pilot symbol and a respective one of the at least one second data symbol, the first pilot signal being determined based on a channel element associated with the first tone and the respective one of the at least one first pilot symbol on the first tone; and

generating an interference-reduced signal for the first tone by canceling the determined first pilot signal from a first combined signal on the first tone.

17. The method of claim 16, further comprising:

determining a second pilot signal on a second tone of the plurality of tones, the second tone carrying a respective one of the at least one second pilot symbol and a respective one of the at least one first data symbol, the second pilot signal being determined based on a second channel element associated with the second tone and the respective one of the at least one second pilot symbol on the second tone; and

generating a second interference-reduced signal for the second tone by canceling the determined second pilot signal from a second combined signal on the second tone.

18. The method of claim 16, wherein a first set of periodic pilot signals from the first UE and a second set of periodic pilot signals from the second UE are shifted by a cyclic shift.

19. The method of claim 16, further comprising providing a cyclic shift to the first UE.

20. The method of claim 16, further comprising de-interleaving the plurality of combined signals to determine a first set of pilot signals from the first UE, first and second code blocks from the first UE, a second set of pilot signals from the second UE, and third and fourth code blocks from the second UE.

21. The method of claim 20, wherein the first set of pilot signals corresponds to a first number tones, the first number tones being equal to half a second number of tones in the third code block.

22. The method of claim 20, wherein the first set of pilot signals from the first UE overlaps with the third code block from the second UE, and the second set of pilot signals from the second UE overlaps with the second code block from the first UE.

23. The method of claim 20, further comprising performing successive decoding after de-interleaving the plurality of combined signals.

24. The method of claim 23, wherein the successive decoding comprises:

decoding the third code block by canceling the first set of pilot signals from the third code block;

decoding the first code block by canceling the third code block from the first code block;

decoding the fourth code block by canceling the first code block from the fourth code block; and

decoding the second code block by canceling the fourth code block from the second code block.

25. A method for wireless communication, comprising:

mapping, at a first user equipment (UE), a first set of pilot symbols and a first set of data symbols to a plurality of tones, each pilot symbol in the first set of pilot symbols being mapped on a tone that is used by a second UE to carry a data symbol; and

providing the mapped first set of pilot symbols and the mapped first set of data symbols for transmission over the plurality of tones.

26. The method of claim 25, wherein a data symbol in the first set of data symbols is mapped on a tone that is used by the second UE to carry a pilot symbol.

27. The method of claim 25, wherein the first set of pilot symbols are transmitted on tones shifted by a cyclic shift from a second set of pilot symbols that is concurrently transmitted by the second UE.

28. The method of claim 27, further comprising receiving the cyclic shift for staggering the first set of pilot symbols from a base station.