ROBUST SENSING OF DVB-T/H TRANSMISSIONS

• US 20120057030A1
• Filed: 04/23/2010
• Published: 03/08/2012
• Est. Priority Date: 05/14/2009
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Ghosh, Monisha, Gaddam, Vasanth
• Granted Patent: US 8,942,336 B2
• Time in Patent Office: Days
• US Class Current: 348/192
• CPC Class Codes: H04L 27/0006 Assessment of spectral gaps suitable for allocating digitally modulated signals, e.g. for carrier allocation in cognitive radio for spectrum sharing between different networks H04W16/14
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/438 Interfacing the downstream path of the transmission network originating from a server, e.g. retrieving encoded video stream packets from an IP network
• CPC Class Codes: H04N 21/6112 involving terrestrial transmission, e.g. DVB-T

Abstract

A method and system is provided for detecting the presence of a DVB (digital video broadcasting) transmission. The method includes receiving an RF (radio frequency) signal in a selected channel (1101); creating signal samples from the received RF signal (1102); creating averaged samples from the signal samples, each averaged sample being an average of a predetermined number of signal samples that are separated by a minimum pilot pattern repetition period from one to the next signal sample (1103); correlating the averaged samples with a reference sequence (1104); and comparing a correlation result with a threshold correlation value (1105).

Claims

1. A method for detecting the presence of a DVB (digital video broadcasting) transmission, comprising:

receiving an RF (radio frequency) signal in a selected channel (1101);

creating signal samples from the received signal (1102);

creating averaged samples from the signal samples, each of the averaged samples being an average of a predetermined number of signal samples that are separated by a minimum pilot pattern repetition period from one to the next signal sample (1103);

correlating the averaged samples with a reference sequence (1104); and

comparing a correlation result with a threshold correlation value (1105).

2. The method of claim 1, further comprising:

calculating a variation in periodicity of correlation peaks from the correlation results; and

comparing the variation with a threshold variation value.

3. The method of claim 1, wherein the minimum pilot pattern repetition period depends on the transmission mode and guard interval duration of the signal.

4. The method of claim 3, further comprising determining the transmission mode by cycling through different transmission modes until the DVB signal is detected.

5. The method of claim 1, wherein the predetermined number of signal samples depends on a sensing time and/or desired performance levels.

6. The method of claim 1, wherein the number of averaged samples depends on how many samples can be accommodated during a quiet period.

7. The method of claim 1, wherein correlating the averaged samples with the reference sequence comprises taking logic operations on the signs of the averaged samples and the reference sequence.

8. The method of claim 1, wherein the reference sequence is generated from pilots and stored in memory.

9. A method for detecting the presence of a DVB (digital video broadcasting) transmission, comprising:

receiving an RF (radio frequency) signal in a selected channel;

creating signal samples from the received signal;

correlating the signal samples with a reference sequence;

calculating an averaged correlation value by taking an average of correlation results corresponding to a predetermined number of signal samples that are separated by a minimum pilot pattern repetition period from one to the next signal sample; and

comparing the averaged correlation value with a threshold correlation value.

10. A system for detecting the presence of a DVB (digital video broadcasting) transmission, comprising:

an RF (radio frequency) front-end module (501) for receiving an RF signal;

a sampling module (502) for creating signal samples from the received RF signal;

a buffer (503) for holding the signal samples;

an accumulating/averaging module (505) for creating averaged samples from the signal samples, each of the averaged samples being an average of a predetermined number of signal samples that are separated by a minimum pilot pattern repetition period from one to the next signal sample;

a memory module (504) for storing a reference sequence;

a correlator (506) for correlating the averaged samples with the reference sequence; and

a threshold detection module (507) for comparing a correlation result with a threshold correlation value.

11. The system of claim 10, wherein the correlator (506) is further configured to calculate a variation in periodicity of correlation peaks from the correlation results, wherein the threshold detection module (507) is further configured to compare the variation with a threshold variation value.

12. The system of claim 10, wherein the minimum pilot pattern repetition period depends on the transmission mode and guard interval duration of the signal.

13. The system of claim 12, further comprising means for determining the transmission mode by cycling through different transmission modes until the DVB signal is detected.

14. The system of claim 10, wherein the predetermined number of signal samples depends on a sensing time and/or desired performance levels.

15. The system of claim 10, wherein the number of averaged samples depends on how many samples can be accommodated during a quiet period.