Patent ID: 7095866

Claim:
A wireless signal transmission apparatus for use with a signal source providing first frequency signals, the signal transmission apparatus comprising: a first transmitter adapted to be coupled to a signal source for receiving first frequency signals, the first transmitter connected to an antenna; a first oscillator in the first transmitter producing a high frequency carrier signal; means for combining the high frequency carrier signal with the first frequency signals to form a first modulated signal transmitted by the antenna; a first receiver remote from the first transmitter connected to an antenna for receiving the first modulated signal; and means coupled to the first receiver for converting the first modulated signal from the high frequency carrier signal of the first transmitter to a second modulated signal including a lower frequency carrier signal and the first frequency signal; the first receiver including: a second oscillator coupled to the first receiver for converting the carrier frequency of the first modulated signal to a lower frequency carrier signal; frequency control means including: means for generating an output upon detecting a first frequency signal in the first modulated signal; means, responsive to the output of the detecting means, for generating a signal proportional to the center frequency of the converted lower frequency carrier signal; means, responsive to the signal proportional to the center frequency, for determining one of a high or low status of the detected center frequency relative to a nominal center frequency, the means generating an output corresponding to the determined one of the high or low status of the detected center frequency; and a controller, responsive to the output for adjusting the frequency of the second oscillator until the output, of the detector means is proportional to the nominal center frequency.