Detection of the presence of television signals embedded in noise using cyclostationary toolbox

• US 9,654,673 B2
• Filed: 01/16/2007
• Issued: 05/16/2017
• Est. Priority Date: 01/17/2006
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Challapali, Kiran, Birru, Dagnachew, Dong, Bin
• Primary Examiner(s): Lewis, Jonathan V
• Application Number:
  US12/160,445
• Publication Number:
  US 20100157066A1
• Time in Patent Office: 3,773 Days
• Field of Search: None
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/42607 for processing the incoming bitstream
• CPC Class Codes: H04N 5/08 Separation of synchronising signals from picture signals
• CPC Class Codes: H04N 5/21 Circuitry for suppressing or minimising disturbance, e.g. moiré or halo
• CPC Class Codes: H04N 5/46 for receiving on more than one standard at will deflecting circuits of multi-standard receivers H04N3/27

Abstract

A method for detecting the presence of a television signal embedded in a received signal including the television signal and noise is disclosed. Either first-order or second order cyclostationary property of the signals may be used for their detection. When the first-order cyclostationary property is used, the following method is used, the method comprising the steps of upsampling the received signal by a factor of N, performing a synchronous averaging of a set of M segments of the upsampled received signal, performing an autocorrelation of the signal; and detecting the presence of peaks in the output of the autocorrelation function. When the second order cyclostationary property of the signal is used, the method comprising the steps of delaying the received signal by a fixed delay (symbol time), multiplying the received signal with the delayed version, looking for a tone (single frequency) in the output.

Claims

1. A method for detecting a television signal, comprising:

receiving, over a frequency spectrum allocated to a licensed user, a signal that comprises the television signal and noise, the television signal exhibiting cyclostationary properties;

determining a peak energy of the received signal by

upsampling the received signal by a factor of N;

performing a synchronous averaging of a set of M segments of the upsampled received signal;

performing an autocorrelation of the signal; and

detecting the presence of peaks in the output of the autocorrelation function; and

determining the television signal periodicity based on the determined peak energy;

wherein the value of N is at least one magnitude greater than the sampling rate of the TV signal, and a search is conducted over B adjacent frequency bins.

2. A device for detecting a television signal, the device comprising:

a processor in communication with a memory, the processor configured to;

receive, over a frequency spectrum allocated to a licensed user, a signal that comprises the television signal and noise, the television signal exhibiting cyclostationary properties;

determine a peak energy of the received signal by

upsampling the received signal by a factor of N;

performing a synchronous averaging of a set of M segments of the upsampled received signal;

performing an autocorrelation of the signal; and

detecting the presence of peaks in the output of the autocorrelation function; and

determine the television signal periodicity based on the determined peak energy;

wherein the value of N is at least one magnitude greater than the sampling rate of the TV signal, and a search is conducted over B adjacent frequency bins.

3. A non-transitory computer readable medium providing instructions to a processing system for detecting a television signal, the instructions causing the processing system to:

receive, over a frequency spectrum allocated to a licensed user, a signal that comprises the television signal and noise, the television signal exhibiting cyclostationary properties;

determine a peak energy of the received signal by

upsampling the received signal by a factor of N;

performing a synchronous averaging of a set of M segments of the upsampled received signal;

performing an autocorrelation of the signal; and

detecting the presence of peaks in the output of the autocorrelation function; and

determine the television signal periodicity based on the determined peak energy;

wherein the value of N is at least one magnitude greater than the sampling rate of the TV signal, and a search is conducted over B adjacent frequency bins.