TECHNIQUES FOR PILOT STREAM REMAPPING IN OFDM WIRELESS COMMUNICATION SYSTEM

• US 20100246515A1
• Filed: 03/11/2010
• Published: 09/30/2010
• Est. Priority Date: 03/24/2009
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: JOSIAM, Kaushik, PI, Zhouyue, TSAI, Jiann-An, KHAN, Farooq, RAMAKRISHNA, Sudhir
• Granted Patent: US 8,879,532 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 1/1819 with retransmission of additional or different redundancy
• CPC Class Codes: H04L 25/0224 using sounding signals
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• 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

A method and base station apparatus for transmitting pilot data in a wireless communication system, and a method and mobile station apparatus for receiving pilot data in a wireless communication system are provided. The method for transmitting pilot data in a wireless communication system includes determining a pilot pattern in at least one resource block for each of one or more pilot streams, and transmitting the one or more pilot streams based on the determined respective pilot pattern in the at least one resource block, wherein the at least one resource block comprises a plurality of subcarriers and a plurality of Orthogonal Frequency Division Multiplexing (OFDM) symbols.

Claims

1. A method for transmitting pilot data in a wireless communication system, the method comprising:

determining a pilot pattern in at least one resource block for each of one or more pilot streams; and

transmitting the one or more pilot streams based on the determined respective pilot pattern in the at least one resource block,

wherein the at least one resource block comprises a plurality of subcarriers and a plurality of Orthogonal Frequency Division Multiplexing (OFDM) symbols.

2. The method of claim 1, wherein the determining of the pilot pattern in the at least one resource block for each of the one or more pilot streams comprises mapping pilot stream k to pilot pattern i based on one of the equations:

i=f(k, N, and at least one of Cell_ID, PRU_ID, STID and frame_indices)

and

k=g(i, N, and at least one of Cell_ID, PRU_ID, STID and frame_indices)

where f and g each denote a functional operation with the combination of parameters within ( ) N denotes the pilot pattern sets, Cell_ID denotes a base station identifier, PRU_ID denotes a scheduled resource block identifier for the targeted mobile station, and STID denotes a station identifier of a targeted mobile station.

3. The method of claim 1, wherein the determining of the pilot pattern in the at least one resource block for each of the one or more pilot streams comprises selecting a pilot stream set s based on the equation:

s=f(at least one of STID, Cell_ID, and PRU_ID)

where f denotes a functional operation with the combination of parameters within ( ), STID denotes a station identifier of a targeted mobile station, Cell_ID denotes a base station identifier, and PRU_ID denotes a scheduled resource block identifier for the targeted mobile station.

4. The method of claim 1, wherein, when the one or more pilot streams comprise a first pilot stream for one of rank-1 and one data stream transmission, the determining of the pilot pattern in the at least one resource block for the first pilot stream comprises:

selecting a pilot stream set s for the first pilot stream, from a pair of pilot stream sets including a pilot stream set ‘

0’ and

a pilot stream set ‘

1’

, based on the equation;

s=mod(k, 2)

where mod denotes a modulus operation, and k denotes a base station identifier.

5. The method of claim 1, wherein, when the one or more pilot streams comprise a first pilot stream for one of rank-1 and one data stream transmission, the determining of the pilot pattern in the at least one resource block for the first pilot stream comprises:

selecting a pilot stream set s for the first pilot stream, from a pair of pilot stream sets including a pilot stream set ‘

0’ and

a pilot stream set ‘

1’

, based on the equation;

s=mod(function(k),

     2)

where mod denotes a modulus operation, k denotes a base station identifier, and function(k) denotes a functional operation with k.

6. The method of claim 5, wherein function(k)=└

k/256┘

where └

x┘

is the largest integer that is smaller than or equal to x.

7. The method of claim 1, wherein the one or more pilot streams comprise one of two pilot streams for two-transmit antenna or two-layer transmission, four pilot streams for four-transmit antenna or four-layer transmission, and eight pilot streams for eight-transmit antenna or eight-layer transmission,

wherein the at least one resource block comprises eighteen subcarriers and one of five, six and seven OFDM symbols, and

wherein the one or more pilot streams are one of dedicated and common.

8. The method of claim 1, wherein the one or more pilot streams are comprised by one or more pilot patterns in one of two and three subcarriers of the at least one resource block.

9. The method of claim 1, wherein, based on the determined respective pilot pattern, the one or more pilot streams are included in two resource blocks such that they are symmetric in at least one of time and frequency.

10. The method of claim 1, wherein, based on the determined respective pilot pattern, the one or more pilot streams are included in a greater number of subcarriers of a resource block used for a first transmission and than a number of subcarriers of a resource block used for Hybrid Automatic Repeat Request (HARQ) retransmission.

11. A method for receiving pilot data in a wireless communication system, the method comprising:

determining a pilot pattern in at least one resource block for a pilot stream; and

receiving the pilot stream based on the determined pilot pattern in the at least one resource block,

wherein the at least one resource block comprises a plurality of subcarriers and a plurality of Orthogonal Frequency Division Multiplexing (OFDM) symbols.

12. The method of claim 11, wherein the determining of the pilot pattern in the at least one resource block for the pilot stream comprises mapping pilot stream k to pilot pattern i based on one of the equations:

i=f(k, N, and at least one of Cell_ID, PRU_ID, STID and frame_indices)

and

k=g(i, N, and at least one of Cell_ID, PRU_ID, STID and frame_indices)

where f and g each denote a functional operation with the combination of parameters within ( ), N denotes the pilot pattern sets, Cell_ID denotes a base station identifier, PRU_ID denotes a scheduled resource block identifier for the targeted mobile station, and STID denotes a station identifier of a targeted mobile station.

13. The method of claim 11, wherein the determining of the pilot pattern in the at least one resource block for the pilot stream comprises selecting a pilot stream s based on the equation:

s=f(at least one of STID, Cell_ID, and PRU_ID)

where f denotes a functional operation with the combination of parameters within ( ), STID denotes a station identifier of a targeted mobile station, Cell_ID denotes a base station identifier, and PRU_ID denotes a scheduled resource block identifier for the targeted mobile station.

14. The method of claim 11, wherein, when the pilot stream is a pilot stream for one of rank-1 and one data stream transmission, the determining of the pilot pattern in the at least one resource block for the pilot stream comprises:

selecting a pilot stream set s for the pilot stream, from a pair of pilot stream sets including a pilot stream set ‘

0’ and

a pilot stream set ‘

1’

based on the equation;

s=mod(k, 2)

where mod denotes a modulus operation, and k denotes a base station identifier.

15. The method of claim 11, wherein, when the pilot stream is a pilot stream for one of rank-1 and one data stream transmission, the determining of the pilot pattern in the at least one resource block for the pilot stream comprises:

selecting a pilot stream set s for the pilot stream, from a pair of pilot stream sets including a pilot stream set ‘

0’ and

a pilot stream set ‘

1’

based on the equation;

s=mod(function(k),

     2)

where mod denotes a modulus operation, k denotes a base station identifier, and function(k) denotes a functional operation with k.

16. The method of claim 15, wherein function(k)=└

k/256┘

where └

x┘

is the largest integer that is smaller than or equal to x.

17. The method of claim 11, wherein pilot stream is one of two pilot streams for two-transmit antenna or two-layer transmission included in the at least one resource block, one of four pilot streams for four-transmit antenna or four-layer transmission included in the at least one resource block, and one of eight pilot streams for eight-transmit antenna or eight-layer transmission included in the at least one resource block,

wherein the at least one resource block comprises eighteen subcarriers and one of five, six and seven OFDM symbols, and

wherein the pilot stream is one of dedicated and common.

18. The method of claim 11, wherein the pilot stream is received in one of two and three subcarriers of the at least one resource block.

19. The method of claim 11, wherein the pilot stream, when received in two resource blocks, is symmetric in at least one of time and frequency.

20. The method of claim 11, wherein the one or more pilot streams are received in a greater number of subcarriers of a resource block used for a first transmission and than a number of subcarriers of a resource block used for Hybrid Automatic Repeat Request (HARQ) retransmission.

21. A base station apparatus for transmitting pilot data in a wireless communication system, the apparatus comprising:

a pilot pattern determiner for determining a pilot pattern in at least one resource block for each of one or more pilot streams;

a subcarrier mapper and an Orthogonal Frequency Division Multiplexing (OFDM) modulator for including the one or more pilot streams in the at least one resource block based on the determined respective pilot pattern; and

a transmitter for transmitting the at least one resource block,

wherein the at least one resource block comprises a plurality of subcarriers and a plurality of OFDM symbols.

22. The apparatus of claim 21, wherein the pilot pattern determiner determines the pilot pattern in the at least one resource block for each of the one or more pilot streams by mapping pilot stream k to pilot pattern i based on one of the equations:

i=f(k, N, and at least one of Cell_ID, PRU_ID, STID and frame_indices)

and

k=g(i, N, and at least one of Cell_ID, PRU_ID, STID and frame_indices)

where f and g each denote a functional operation with the combination of parameters within ( ), N denotes the pilot pattern sets, Cell_ID denotes a base station identifier, PRU_ID denotes a scheduled resource block identifier for the targeted mobile station, and STID denotes a station identifier of a targeted mobile station.

23. The apparatus of claim 21, wherein the pilot pattern determiner determines the pilot pattern in the at least one resource block for each of the one or more pilot streams by selecting a pilot stream set s based on the equation:

s=f(at least one of STID, Cell_ID, and PRU_ID)

where f denotes a functional operation with the combination of parameters within ( ), STID denotes a station identifier of a targeted mobile station, Cell_ID denotes a base station identifier, and PRU_ID denotes a scheduled resource block identifier for the targeted mobile station.

24. The apparatus of claim 21, wherein, when the one or more pilot streams comprise a first pilot stream for one of rank-1 and one data stream transmission, the pilot pattern determiner determines the pilot pattern in the at least one resource block for the first pilot stream by selecting a pilot stream set s for the first pilot stream, from a pair of pilot stream sets including a pilot stream set ‘

0’ and

a pilot stream set ‘

1’

, based on the equation;

s=mod(k, 2)

where mod denotes a modulus operation, and k denotes a base station identifier.

25. The apparatus of claim 21, wherein, when the one or more pilot streams comprise a first pilot stream for one of rank-1 and one data stream transmission, the pilot pattern determiner determines the pilot pattern in the at least one resource block for the first pilot stream by selecting a pilot stream set s for the first pilot stream, from a pair of pilot stream sets including a pilot stream set ‘

0’ and

a pilot stream set ‘

1’

, based on the equation;

s=mod(function(k),

     2)

where mod denotes a modulus operation, and k denotes a base station identifier, function(k) denotes a functional operation with k.

26. The apparatus of claim 25, wherein function(k)=└

k/256┘

where └

x┘

is the largest integer that is smaller than or equal to x.

27. The apparatus of claim 21, wherein the one or more pilot streams comprise one of two pilot streams for two-transmit antenna or two-layer transmission, four pilot streams for four-transmit antenna or four-layer transmission, and eight pilot streams for eight-transmit antenna or eight-layer transmission,

wherein the at least one resource block comprises eighteen subcarriers and one of five, six and seven OFDM symbols, and

wherein the one or more pilot streams are one of dedicated and common.

28. The apparatus of claim 21, wherein, based on the determined respective pilot pattern, the one or more pilot streams are included in one of two and three subcarriers of the at least one resource block.

29. The apparatus of claim 21, wherein, based on the determined respective pilot pattern, the one or more pilot streams are included in two resource blocks such that they are symmetric in at least one of time and frequency.

30. The apparatus of claim 21, wherein, based on the determined respective pilot pattern, the one or more pilot streams are included in a greater number of subcarriers of a resource block used for a first transmission and than a number of subcarriers of a resource block used for Hybrid Automatic Repeat Request (HARQ) retransmission.

31. A mobile station apparatus for receiving pilot data in a wireless communication system, the apparatus comprising:

a receiver for receiving a signal including pilot stream in at least one resource block;

a pilot pattern determiner for determining a pilot pattern in at least one resource block for the pilot stream; and

an Orthogonal Frequency Division Multiplexing (OFDM) demodulator and a subcarrier demapper for extracting the pilot stream from the at least one resource block based on the determined pilot pattern,

wherein the at least one resource block comprises a plurality of subcarriers and a plurality of OFDM symbols.

32. The apparatus of claim 31, wherein the pilot pattern determiner determines the pilot pattern in the at least one resource block for the pilot stream by mapping pilot stream k to pilot pattern i based on one of the equations:

i=f(k, N, and at least one of Cell_ID, PRU_ID, STID and frame_indices)

and

k=g(i, N, and at least one of Cell_ID, PRU_ID, STID and frame_indices)

where f and g each denote a functional operation with the combination of parameters within ( ), N denotes the pilot pattern sets, Cell_ID denotes a base station identifier, PRU_ID denotes a scheduled resource block identifier for the targeted mobile station, and STID denotes a station identifier of a targeted mobile station.

33. The apparatus of claim 31, wherein the pilot pattern determiner determines the pilot pattern in the at least one resource block for the pilot stream by selecting a pilot stream set s based on the equation:

s=f(at least one of STID, Cell_ID, and PRU_ID)

where f denotes a functional operation with the combination of parameters within ( ), STID denotes a station identifier of a targeted mobile station, Cell_ID denotes a base station identifier, and PRU_ID denotes a scheduled resource block identifier for the targeted mobile station.

34. The apparatus of claim 31, wherein, when the pilot stream is a pilot stream for one of rank-1 and one data stream transmission, the pilot pattern determiner determines the pilot pattern in the at least one resource block for the pilot stream by selecting a pilot stream set s for the pilot stream, from a pair of pilot stream sets including a pilot stream set ‘

0’ and

a pilot stream set ‘

1’

, based on the equation;

s=mod(k, 2)

where mod denotes a modulus operation, and k denotes a base station identifier.

35. The apparatus of claim 31, wherein, when the pilot stream is a pilot stream for one of rank-1 and one data stream transmission, the pilot pattern determiner determines the pilot pattern in the at least one resource block for the pilot stream by selecting a pilot stream set s for the pilot stream, from a pair of pilot stream sets including a pilot stream set ‘

0’ and

a pilot stream set ‘

1’

, based on the equation;

s=mod(function(k),

     2)

where mod denotes a modulus operation, and k denotes a base station identifier, function(k) denotes a functional operation with k.

36. The apparatus of claim 35, wherein function(k)=└

k/256┘

where └

x┘

is the largest integer that is smaller than or equal to x.

37. The apparatus of claim 31, wherein pilot stream is one of two pilot streams for two-transmit antenna or two-layer transmission included in the at least one resource block, one of four pilot streams for four-transmit antenna or four-layer transmission included in the at least one resource block, and one of eight pilot streams for eight-transmit antenna or eight-layer transmission included in the at least one resource block,

wherein the at least one resource block comprises eighteen subcarriers and one of five, six and seven OFDM symbols, and

wherein the pilot stream is one of dedicated and common.

38. The apparatus of claim 31, wherein the pilot stream is received in one of two and three subcarriers of the at least one resource block.

39. The apparatus of claim 31, wherein the pilot stream, when received in two resource blocks, is symmetric in at least one of time and frequency.

40. The apparatus of claim 31, wherein the pilot stream is received in a greater number of subcarriers of a resource block used for a first transmission and than a number of subcarriers of a resource block used for Hybrid Automatic Repeat Request (HARQ) retransmission.