WINDOW POSITION OPTIMIZATION FOR PILOT-AIDED OFDM SYSTEM

• US 20100014600A1
• Filed: 07/18/2008
• Published: 01/21/2010
• Est. Priority Date: 07/18/2008
• Status: Active Grant

• Current Assignee: Advanced Micro Devices, Inc.
• Original Assignee: Advanced Micro Devices, Inc.
• Inventors: Schaffer, Troy, Huang, Feng, Li, Yan, Rajagopal, Ravikiran
• Granted Patent: US 8,625,686 B2
• Time in Patent Office: Days
• US Class Current: 375/260
• CPC Class Codes: H04L 25/0212 of impulse response
• CPC Class Codes: H04L 25/022 of frequency response
• CPC Class Codes: H04L 25/0232 by interpolation between sounding signals
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04L 27/2662 Symbol synchronisation

Abstract

A window position optimization for a pilot-aided OFDM system is disclosed. A method of reducing aliasing in an orthogonal frequency division multiplexing (OFDM) system, using window optimization and pilots comprises receiving an RF signal including a pilot, generating a channel frequency response estimate, interpolating the channel estimate to calculate a pilot carrier frequency response, and dynamically selecting a window to capture a channel impulse response to prevent aliasing.

Claims

1. A method of reducing aliasing in an orthogonal frequency division multiplexing (OFDM) system, the method comprising:

selecting at least one window, wherein the window minimizes a difference between a first channel estimate based on a first pilot signal and a second channel estimate based on a second pilot signal.

2. The method of claim 1, further comprising:

determining a channel impulse response based on the selected window.

3. The method of claim 1, further comprising:

selecting a plurality of windows and generating a first channel estimate and a second channel estimate associated with each window;

selecting one of the plurality of windows as a preferred window;

determining a channel impulse response based on the preferred window.

4. The method of claim 1, further comprising:

determining a channel impulse response based on the selected window; and

shifting the channel impulse response into the selected window.

5. The method of claim 1, wherein the OFDM system is a digital video broadcasting-terrestrial (DVB-T) system.

6. The method of claim 1, wherein the OFDM system is a integrated services digital broadcasting-terrestrial (ISDB-T) system.

7. The method of claim 1, wherein the first pilot signal is a transmission parameter signaling (TPS) signal.

8. The method of claim 1, wherein the first pilot signal is a transmission and multiplexing configuration control (TMCC) signal.

9. An orthogonal frequency division multiplexing (OFDM) receiver, the OFDM receiver comprising:

a synchronization and channel estimation (SCE) block configured to select at least one window, wherein the window minimizes the difference between a first channel estimate based on a first pilot signal and a second channel estimate based on a second pilot signal.

10. The OFDM receiver of claim 9, wherein the SCE block is further configured to determining a channel impulse response based on the selected window.

11. The OFDM receiver of claim 9, wherein the SCE block is further configured to select a plurality of windows and generating a first channel estimate and a second channel estimate associated with each window and to select one of the plurality of windows as a preferred window and then determine a channel impulse response based on the preferred window.

12. The OFDM receiver of claim 9, wherein the SCE block is further configured to determine a channel impulse response based on the selected window, and to shift the channel impulse response into the selected window.

13. The OFDM receiver of claim 9, wherein the OFDM system is a digital video broadcasting-terrestrial (DVB-T) system.

14. The OFDM receiver of claim 9, wherein the OFDM system is a integrated services digital broadcasting-terrestrial (ISDB-T) system.

15. The OFDM receiver of claim 9, wherein the first pilot signal is a transmission parameter signaling (TPS) signal.

16. The OFDM receiver of claim 9, wherein the first pilot signal is a transmission and multiplexing configuration control (TMCC) signal.

17. A machine readable storage medium having a stored set of instructions executable by a machine, the instructions when executed are adapted to perform operations comprising:

select at least one window, wherein the window minimizes the difference between a first channel estimate based on a first pilot signal and a second channel estimate based on a second pilot signal.

18. A computer-readable medium containing a first set of instructions adapted to create a processor, wherein the processor is configured to implement a second set of instructions, the second set of instructions comprising:

instructions to select at least one window, wherein the window minimizes the difference between a first channel estimate based on a first pilot signal and a second channel estimate based on a second pilot signal