Pilot designing method in an uplink OFDMA system

• US 7,710,918 B2
• Filed: 03/11/2005
• Issued: 05/04/2010
• Est. Priority Date: 03/11/2004
• Status: Active Grant

• Current Assignee: Korea Advanced Institute of Science and Technology, Samsung Electronics Co. Ltd.
• Original Assignee: Korea Advanced Institute of Science and Technology, Samsung Electronics Co. Ltd.
• Inventors: Jung, Young-Ho, Nam, Seung-Hoon, Lee, Yong-Hoon, Hwang, Chan-Soo, Chung, Jae-Hak, Park, Hong-Sun
• Primary Examiner(s): Kincaid; Lester
• Assistant Examiner(s): MITCHELL, NATHAN A
• Application Number:
  US11/078,157
• Publication Number:
  US 20050243939A1
• Time in Patent Office: 1,880 Days
• Field of Search: 370/321, 370336-338, 370345-348, 370/328, 370/329
• US Class Current: 370/329
• CPC Class Codes: H04L 25/0204 of multiple channels
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 25/0232 by interpolation between sounding signals
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver

Abstract

A pilot designing method in an uplink OFDMA system is provided. In the uplink OFDMA system, communications are carried out in a frame divided into time-frequency lattices, and each time-frequency lattice includes a plurality of data symbol periods and a plurality of pilot symbol periods intermittently arranged with respect to the data symbol periods. The frame is divided into a plurality of blocks. The blocks are allocated to the terminals. A predetermined allocated pilot time-frequency lattice is shared between adjacent terminals.

Claims

1. A pilot designing method in an uplink orthogonal frequency division multiple access (OFDMA) system including a plurality of terminals where communications are carried out in a frame divided into time-frequency lattices, each time-frequency lattice being identified by frequency-axis subcarrier indexes and time-axis symbol period indexes and including a plurality of intermittently arranged pilot subcarriers, comprising the steps of:

dividing the frame into transport blocks of a predetermined size and allocating the transport blocks to terminals by the uplink OFDMA system; and

sharing pilot subcarriers of adjacent transport blocks allocated to different terminals in at least one symbol period.

2. The pilot designing method of claim 1, wherein the pilot subcarriers are shifted to other subcarrier indexes at predetermined symbol period intervals.

3. The pilot designing method of claim 2, wherein a transport block allocated to each terminal is shared by at least two antennas of the terminal.

4. The pilot designing method of claim 3, wherein the antennas map orthogonal pilot signals to pilot subcarriers in the transport block.

5. The pilot designing method of claim 2, wherein a pilot subcarrier is shared by the different terminals for four symbol periods.

6. The pilot designing method of claim 5, wherein a transport block allocated to each terminal is shared by at least two antennas of the terminal.

7. The pilot designing method of claim 6, wherein the pilot subcarrier is selectively allocated to the two antennas of the terminal for two successive symbol periods.

8. The pilot designing method of claim 7, wherein a pilot signal is mapped to pilot subcarriers having different indexes in the transport block for different symbol periods.

9. The pilot designing method of claim 6, wherein the pilot subcarrier is allocated to the two antennas of the terminal for the same two successive symbol periods.

10. The pilot designing method of claim 9, wherein a pilot signal is mapped to pilot subcarriers having different indexes in the transport block for different symbol periods.

11. The pilot designing method of claim 10, wherein the pilot signals mapped to the two antennas of the terminal are orthogonal to each other.

12. The pilot designing method of claim 5, wherein the pilot subcarrier is selectively allocated to at least two antennas of the terminal for a different symbol period.

13. The pilot designing method of claim 12, wherein a pilot signal is mapped to pilot subcarriers having different indexes in the transport block for different symbol periods.

17. The pilot designing method of claim 1, further comprising the step of:

receiving a frame with the shared pilot subcarriers between the adjacent transport blocks; and

estimating a channel of each of the terminals using pilot signals included in the received shared pilot subcarriers.

14. A pilot designing method in an uplink orthogonal frequency division multiple access (OFDMA) system in, where communications are carried out in a frame divided into time-frequency lattices, each tame-frequency lattice being identified by frequency-axis subcarrier indexes and time-axis symbol period indexes and including a plurality of intermittently arranged pilot symbol periods, comprising the steps of:

dividing the frame into transport blocks of a predetermined size and allocating the transport blocks to terminals; and

sharing pilot symbol periods of adjacent transport blocks allocated to different terminals in at least one subcarrier.

15. The pilot designing method of claim 14, wherein a transport block allocated to each terminal is shared by at least two antennas of the terminal.

16. The pilot designing method of claim 15, wherein the antennas map orthogonal pilot signals to pilot symbol periods in the transport block.