Patent ID: 7937053
Filing Date: 2011-05-03
Classification: H04N

Abstract:
1. A method for receiving a station signal, the method comprising: receiving a radio frequency signal and converting the radio frequency signal to a first intermediate frequency (IF) signal; demodulating the first IF signal to a baseband signal and obtaining a demodulation signal, the demodulation signal being a result of differentiating a phase of the baseband signal; determining whether a DC level of the demodulation signal has an S-curve characteristic at a specific frequency according to the demodulation signal; and determining the specific frequency as a first station frequency, locating a first station signal from the radio frequency signal according to the first station frequency, and receiving the first station signal if the DC level of the demodulation signal has the S-curve characteristic at the specific frequency; wherein if the DC level of the demodulation signal is positive and the absolute value of the DC level of the demodulation signal is larger than a first threshold value at a first frequency lower than the specific frequency, the absolute value of the DC level of the demodulation signal is less than a second threshold value at the specific frequency, the DC level of the demodulation signal is negative, and the absolute value of the DC level of the demodulation signal is larger than the first threshold value at a second frequency higher than the specific frequency, it is determined that the DC level of the demodulation signal has the S-curve characteristic at the specific frequency.