Salvatore F Amoroso Deceased130 Huntington Ave, New Haven, CT 06512

4411018, Oct 18, 1983

Oct 18, 1983

6/313104

Salvatore Amoroso - Fairfield CT

United Technologies Corporation - Hartford CT

H04B 140

455 75

A single channel, or push-to-talk transceiver includes a switch-controlled Gunn oscillator for generating the carrier frequency during transmission and a continuously operating local oscillator for demodulation of a received signal in the receive mode. When the push-to-talk switch is depressed, the transmit oscillator is energized and leakage signals cross the circulator to the receiver portion of the transceiver. An RF AFC loop between the transmitter and receiver portions includes a low-pass filter at the preamplifier output which serves as a simple slope discriminator. This output is detected and used to close an electronic servo loop. Once closed, this servo loop locks the transmit oscillator frequency relative to the local oscillator thereby preventing frequency drift during warm-up.

3935533, Jan 27, 1976

Aug 29, 1974

5/501721

Salvatore Amoroso - Fairfield CT

United Technologies Corporation - Hartford CT

H04B 140

325 20

A voltage variable oscillator feeds an FM modulated signal to be transmitted to an orthomode transducer connected to a dual polarization antenna, another port of the orthomode transducer feeding received FM signals to a single ended mixer, the output of which is passed through an FM receiver. The orthomode transducer leaks a portion of the transmitted wave to the single ended mixer, for use in lieu of a local oscillator, thereby limiting the requirements to a single microwave oscillator. The output of the FM receiver is applied to a cancellation circuit where the transmitter modulation is cancelled from the FM receiver output in response to delayed transmitter input signals. The output of the cancellation circuit comprises the receiver output, and is used as the signal input of a phase sensitive demodulator, the phase reference input of which is the delayed transmitter modulation, the phase sensitive demodulator controlling the gain of a variable gain amplifier so as to provide complete closed loop automatic gain control, limiting the frequency excursion of the oscillator in such a fashion as to permit complete cancellation of the transmitter input modulation from the receiver output modulation, despite any variations in circuit scale factor. In a system employing more than one transceiver having the same receiver IF frequency, an automatic frequency control loop is provided in one of the transceivers, and nominal or stabilized frequency control is applied in the other, whereby one frequency is slave to the other separated by the IF frequency; in addition, means are provided in conjunction with the cancellation circut to accommodate the opposite polarity of the discriminator output in two different transceivers communicating with one another resulting from discrimination of opposite sidebands.

4509050, Apr 2, 1985

Aug 30, 1982

6/413007

Salvatore Amoroso - Fairfield CT
Russell W. Conklin - Stratford CT

United Technologies Corporation - Hartford CT

G01S 734

343 5SM

An automatic adaptive sensitivity time control for a ground mapping radar comprises the dynamic range of radar returns for presentation on a video display. A feedback loop including a differential amplifier senses the magnitude of a signal presented to a limit amplifier and compares the same with a clutter threshold reference potential. A low-pass filter in the feedback loop then smooths or averages the clutter deviation from the reference potential to adjust the clutter level out of a log IF amplifier so that the nominal clutter signal level of close-in returns does not exceed a predetermined magnitude. A second embodiment includes a dual time constant filter in the feedback loop. A comparator circuit senses the leading edge of clutter return signals and switches the feedback loop to its faster time constant mode allowing dynamic compression of smaller time constant pulses.