Silence based attenuation for enhanced idle-channel FM or other receiver co-existence with a coexisting radio and circuits, processes, and systems

摘要

An electronic circuit (100) for use in a wireless receiver (1720). The circuit (100) includes an audio demodulator (15), an audio envelope portion (35) operable to deliver an audio envelope signal, a high pass filter (38) coupled between the audio demodulator (15) and the audio envelope portion (35), a volume control (25) fed by the audio demodulator (15) and operable to provide a controllable audio signal output, and a controller (45) responsive to the audio envelope portion (35) to provide an attenuation control to the volume control (25). Other circuits, receivers, processes of operation, processes of manufacture, and processes of testing are disclosed.

主权项

1. An electronic circuit for use in a wireless receiver, the circuit comprising:
an audio demodulator; an audio envelope portion operable to deliver an audio envelope signal; a high pass filter coupled between said audio demodulator and said audio envelope portion; a volume control fed by said audio demodulator and operable to provide a controllable audio signal output; and a controller responsive to said audio envelope portion to provide an attenuation control to said volume control; wherein said audio demodulator includes a stereo demodulator, said high pass filter is coupled to receive a monaural signal input from a portion of said audio demodulator, said high pass filter is fed with audio channels from said stereo demodulator, and said high pass filter is responsive to the monaural signal input to provide a direct current (DC) estimation, and said high pass filter includes a subtractor circuit fed with the audio channels and providing an output with the DC estimation subtracted out, said audio envelope portion responsive to such output.