Telecommunications – Transmitter and receiver at separate stations – Plural transmitters or receivers
Patent
1996-04-01
1998-01-20
Urban, Edward F.
Telecommunications
Transmitter and receiver at separate stations
Plural transmitters or receivers
455314, 455 65, 244 314, H04B 702, H07B 1500
Patent
active
057110093
ABSTRACT:
An apparatus for the error free transmission of PCM/FM telemetry data. The pparatus comprises a first mixer for receiving an RF signal which has a first frequency and which is the carrier for the PCM/FM telemetry data. A variable frequency oscillator provides a local oscillator signal to the first mixer which is an offset for the RF signal. The first mixer then mixes the RF signal with the local oscillator signal resulting in the RF signal having a second frequency. This RF signal is supplied to a second mixer which mixes the RF signal with a fixed frequency signal provided by a fixed frequency oscillator. The RF signal provided by the second mixer now has a third frequency and is supplied to a bandpass filter. The frequency of the local oscillator signal is adjusted so that the offset to the RF signal provided by the first mixer is approximately one half of the intermediate frequency bandwidth of the bandpass filter. An analog signal is provided by the bandpass filter with the bandpass filter attenuating the signal in one state resulting in a substantial difference between the amplitude of the signal in the one state and its amplitude in another state. The analog signal is next supplied to an AM detector. The AM detector then provides at its output a PCM telemetry data signal which has voltage spikes removed from the PCM telemetry data signal.
REFERENCES:
patent: H1288 (1994-02-01), Lusk
patent: 3176231 (1965-03-01), Vallese et al.
patent: 3745464 (1973-07-01), Lee
patent: 3869673 (1975-03-01), Close
patent: 4003006 (1977-01-01), Mandeville et al.
patent: 4088955 (1978-05-01), Baghdady
patent: 4326294 (1982-04-01), Okamoto et al.
patent: 4430744 (1984-02-01), Johnson
patent: 4499606 (1985-02-01), Rambo
patent: 4566133 (1986-01-01), Rambo
patent: 4710975 (1987-12-01), Okamoto et al.
patent: 5010584 (1991-04-01), Seki
patent: 5241544 (1993-08-01), Jasper et al.
patent: 5483694 (1996-01-01), Bartels et al.
Armstrong Darnell R.
Kalmbaugh David S.
Sliwka Melvin J.
The United States of America as Represented by the Secretary of
Urban Edward F.
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