Patent ID: 6178314
Filing Date: 2001-01-23
Classification: H03G,H04B

Abstract:
A radio receiver for receiving broadcasts wherein individual broadcasts have different respective bandwidth usage with respect to a standard channel spacing, said radio receiver comprising:an intermediate frequency channel filter for filtering an intermediate frequency signal according to a bandwidth selectable between at least a wide bandwidth including substantially all of a broadcast channel or a narrow bandwidth including less than all of said broadcast channel;a first controller coupled to said intermediate frequency channel filter for detecting the presence of interfering signals from an undesired source, said first controller selecting said wide bandwidth when interfering signals are not detected and selecting said narrow bandwidth when interfering signals are detected;a demodulator coupled to said intermediate frequency channel filter for demodulating a filtered intermediate frequency signal to produce a baseband signal;a noise reduction lowpass filter coupled to said demodulator for filtering said baseband signal, said noise reduction filter having a controllable upper cutoff frequency; anda second controller coupled to said noise reduction filter for controlling said upper cutoff frequency in response to a frequency content of said baseband signal.