Delay type probe antenna noise cancellation system

• US 3,895,385 A
• Filed: 06/29/1956
• Issued: 07/15/1975
• Est. Priority Date: 06/29/1956
• Status: Expired due to Term

• Current Assignee: Frederick C. Alpers
• Original Assignee: Frederick C. Alpers
• Inventors: Alpers, Frederick C.
• Primary Examiner(s): Wilbur, Maynard R.
• Assistant Examiner(s): Berger, Richard E.
• Application Number:
  US03/595,020
• Time in Patent Office: 6,955 Days
• Field of Search: 343/100,113,5A,115,16,120
• US Class Current: 342/421
• CPC Class Codes: G01S 3/06 Means for increasing effective directivity, e.g. by combining signals having differently oriented directivity characteristics or by sharpening the envelope waveform of the signal derived from a rotating or oscillating beam antenna comparing amplitude of signals having differently oriented directivity characteristics to determine direction G01S3/16, G01S3/28

Abstract

1. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising means for receiving signals from said source through a directional antenna and a probe antenna, and means for dividing the signal from said directional antenna by the signal from said probe antenna over a wide dynamic range of modulation.

Claims

1. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising means for receiving signals from said source through a directional antenna and a probe antenna, and means for dividing the signal from said directional antenna by the signal from said probe antenna over a wide dynamic range of modulation.

2. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising means for receiving signals from said source through a directional antenna and a probe antenna, and means for dividing the signal from said directional antenna by the signal from said probe antenna over a wide dynamic range of modulation, said dividing means including an automatic gain control circuit and a division circuit.

3. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising means for receiving signals from said source through a directional antenna and a probe antenna, means for eliminating other undesired signals from the desired probe and directional antenna signals including means for discriminating and selecting said desired signals on a time basis, and means for dividing the signal from said directional antenna by the signal from said probe antenna over a wide dynamic range of modulation.

4. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising means for receiving signals from said source through a directional antenna and a probe antenna, means for combining the signal from said probe antenna with a delayed signal from said directional antenna, means for separating and selecting only the desired portion of saId probe and directional antenna signals including means for gating the desired portions of said signal and discriminating against the undesired portions of said signals on a time basis, and means for dividing the signal from said directional antenna by the signal from said probe antenna over a wide dynamic range of modulation.

5. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising a directional antenna, a probe antenna, means for delaying the signal from one of said antennas, means for combining said delayed signal with the signal from the other of said antennas, means for separating said directional and probe signals, automatic gain control means adapted to receive the probe signal and apply a gain control to said combined signals, and a division circuit adapted to receive and divide the directional signal by the probe signal, and provide an output proportional to the noise-free directional information.

6. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising a directional antenna, a probe antenna, means for delaying the signal from one of said antennas, means for combining said delayed signal with the signal from the other of said antennas, means for separating and gating only the desired portions of said directional and probe signals, automatic gain control means adapted to receive the probe signal and apply a gain control to said combined signals, and a division circuit adapted to receive and divide the directional signal by the probe signal and provide an output proportional to the noise-free directional information.

7. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising a directional antenna, a probe antenna, means for delaying the signal from said directional antenna, means for combining said delayed signal with the signal from said probe antenna, a discriminating gate circuit, signal selector means associated with said gate circuit for separating and selecting only the desired portions of said directional and probe signals, automatic gain control means adapted to receive the probe signal and apply a gain control to said combined signals, a division circuit adapted to receive and divide the directional signal by the probe signal, and provide an output proportional to the noise-free directional information, and a blanking circuit associated with said discriminating gate circuit and adapted to eliminate the undesired trailing portion of said probe antenna signal prior to combining said signals.

8. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising a directional antenna, a probe antenna, means for delaying the signal from said directional antenna, means for combining said delayed signal with the signal from said probe antenna, means for amplifying and detecting said combined signal, means for separating said directional probe signals, automatic gain control means adapted to receive the probe signal and apply a gain control to said amplifying means, a division circuit adapted to receive and divide the directional signal by the probe signal and provide an output proportional to the noise-free directional information, commutator circuit adapted to receive the output from said dividing circuit, and directional output circuits adapted to receive and utilize the output from said commutator circuit.

9. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising a directional antenna, a probe antenna, a delay line associated with said directional antenna, a main amplifier adapted to combine the directional signal from said delay line and the probe signal from said probe antenna, a probe signal selector adapted to receive said combined signals and pass the desired portion of the probe signal onlY, a directional signal selector adapted to receive said combined signal and pass only the desired portion of the directional signal, an automatic gain control circuit adapted to receive the probe signal and apply a gain control to said main amplifier, and a division circuit adapted to receive a probe signal from said probe signal selector and a directional signal from said directional signal selector and provide an output which is the quotient of the directional signal divided by the probe signal.

10. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising a directional antenna, a probe antenna, a delay line associated with said directional antenna, a main amplifier adapted to combine the directional signal from said delay line and the probe signal from said probe antenna, a discriminating gate circuit associated with said main amplifier adapted to receive the combined signals therefrom, a pulse generator adapted to receive the gate from said discriminating gate circuit and provide a pulse output, a probe signal selector adapted to receive said combined signals and the pulse output from said pulse generator and pass the probe signal only, a pulse delay circuit associated with said pulse generator, a directional signal selector adapted to receive said combined signal and said delayed pulse and pass only the directional signal, an automatic gain control circuit adapted to receive the probe signal and apply a gain control to said main amplifier, and a division circuit adapted to receive a probe signal from said probe signal selector and a directional signal from said directional signal selector and provide an output which is the quotient of the directional signal divided by the probe signal.

11. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising a directional antenna, a probe antenna, a blanking circuit associated with said probe antenna, a delay line associated with said directional antenna, a main amplifier adapted to combine the directional signal from said delay line and the probe signal from said blanking circuit, a discriminating gate circuit associated with said main amplifier adapted to receive the combined signals therefrom and apply a voltage gate to said blanking circuit, a pulse generator adapted to receive the gate from said discriminating gate circuit and provide a pulse output, a probe signal selector adapted to receive said combined signals and the pulse output from said pulse generator and pass the probe signal only, a pulse delay circuit associated with said pulse generator, a directional signal selector adapted to receive said combined signal and said delayed pulse and pass only the directional signal, an automatic gain control circuit adapted to receive the probe signal and apply a gain control to said main i-f amplifier inversely proportional to the probe signal, and a division circuit adapted to receive a probe signal from said probe signal selector and a directional signal from said directional signal selector and provide an output which is the quotient of the directional signal divided by the probe signal.

12. A system for obtaining accurate directional information with regard to the relative position of a pulsed radar source comprising a directional antenna, a probe antenna, a mixer associated with each of said antennas, a local oscillator adapted to apply a local oscillator signal to both of said mixers, a blanking circuit associated with the mixer in said probe antenna circuit, an i-f amplifier for balancing associated with the mixer in said directional antenna channel, an i-f delay line associated with said balancing amplifier, a main i-f amplifier adapted to combine the directional signal from said i-f delay line and the probe signal from said blanking circuit, a detector associated with said main i-f amplifier, a video amplifier associatEd with said detector, a discriminating gate circuit associated with said video amplifier and adapted to receive the combined signals therefrom and apply a voltage gate to said blanking circuit, a pulse generator adapted to receive the gate from said discriminating gate circuit and provide a pulse output, a probe signal selector adapted to receive the combined signals from said video amplifier and the pulse output from said pulse generator and pass the desired portion of the probe signal only, a delay circuit associated with said pulse generator, a directional signal selector adapted to receive said combined signal and said delayed pulse and pass only the desired portion of the directional signal, an automatic gain control circuit adapted to receive the probe signal and apply a gain control to said main i-f amplifier inversely proportional to the probe signal, a division circuit adapted to receive the probe signal from said probe signal selector and the directional signal from said directional signal selector and provide an output which is the quotient of the directional signal divided by the probe signal, a balancing circuit adapted to receive the noise-free directional signal from said dividing circuit and apply a slow-acting feedback to said i-f amplifier for balancing, a commutator circuit adapted to receive the noise-free directional information from said division circuit and directional reference information from said directional antenna, and directional output circuits adapted to utilize the output from said commutator.