| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a system for detecting a digital TV leakage signal and specifying a place in a fiber/coaxial hybrid (HFC) network.SOLUTION: The system has a head end unit 102 and a leakage detection unit 119. The head end unit receives a TV signal at a head end 101 to use it as a reference signal, the reference signal is sampled at a rate corresponding to a time reference signal to generate a reference signal sample, and the sample and a time stamp are transmitted to the leakage detection unit. The detection unit has a cross correlation processor 114. A leakage signal is sampled at a rate corresponding to the time reference signal to generate a leakage signal sample. The cross correlation processor performs cross correlation between the reference signal sample and the leakage signal sample to generate a cross correlation function having a peak, and a TV leakage signal is detected from the peak.</p> |
