System and method for detecting rated maximum system deviation (RMSD) and alleviating RMSD mismatch

摘要

An FM audio receiver can include a mono/stereo detector that causes the audio receiver to output either a monophonic or a stereophonic signal based on a received pilot tone energy. An accurate operation of the receiver, including but not limited to correct decoding of monophonic/stereophonic reception, can be based on the receiver operating with the same rated maximum system deviation (RMSD) as the received signal itself. Aspects of the disclosure describe a system and method of detecting and matching a receiver's RMSD to that of a received signal by demodulating a carrier bearing a an input signal over a first bandwidth, extracting a pilot energy signal from the input signal, and demodulating the carrier bearing the input signal over a second bandwidth if the pilot energy signal is within a pilot energy range for a first predetermined amount of time.

主权项

1. A method of receiving, comprising:
demodulating a modulated carrier bearing a first signal by a demodulator configured to operate with a plurality of modes including at least a first mode to demodulate the modulated carrier bearing the first signal based on a first rated maximum system deviation (RMSD) value of the modulated carrier, the demodulator operating in the first mode; extracting a second signal from the first signal; generating a third signal based on the second signal, the third signal being fed back to the demodulator; and instructing, by the third signal, the demodulator to change from the first mode to a second mode to demodulate the modulated carrier bearing the first signal based on a second rated maximum system deviation (RMSD) value of the modulated carrier.