ANTENNA SELF-TEST SYSTEMS

• US 3,697,876 A
• Filed: 10/17/1969
• Issued: 10/10/1972
• Est. Priority Date: 10/17/1969
• Status: Expired due to Term

• Current Assignee: Arthur R. Whitty, Louis J. Kachavos, Robert Robbins
• Original Assignee: Arthur R. Whitty, Louis J. Kachavos, Robert Robbins
• Inventors: Robbins, Robert, Whitty, Arthur R., Kachavos, Louis J.
• Primary Examiner(s): Griffin, Robert L.
• Assistant Examiner(s): Weinstein, Kenneth W.
• Application Number:
  US04/867,245
• Time in Patent Office: 1,089 Days
• Field of Search: 325/67,133,363 343/17.7,703
• US Class Current: 342/47
• CPC Class Codes: G01R 29/10 Radiation diagrams of antennas

Abstract

An antenna system is provided, in which a small test probe positioned in the antenna cavity is coupled to a system self-test unit. A signal, designed to exercise the primary functions of the system under evaluation is transmitted between the antenna and the test probe and then conducted to the actual system or the self-test unit for processing. This signal activates the appropriate system which is then evaluated for actual performance.

Claims

1. A system for receiving energy, said system having a first receiver apparatus coupled to an antenna capable of radiating and receiving energy, wherein the improvement comprises:

an antenna test probe capable of radiating and receiving energy, said test probe being positioned in close proximity to said antenna and within the field of radiation of said antenna;

test means adapted to apply a test signal having prearranged information to provide a predictable result to said test probe, said test means comprising a signal generator means arranged to generate a first signal having fixed frequency, a sweep oscillator means arranged to receive said first signal and to generate a second signal which varies in frequency between a third and a fourth frequency, and an oscillator means arranged to generate a fifth signal having a sixth frequency, said oscillator means adapted to receive said second signal and to modulate said fifth signal thereby to generate a seventh signal which varies in frequency between an eighth and ninth frequency, said eight frequency being less and said ninth frequency being greater than the frequency of said fifth signal, and circuit means arranged to couple said seventh signal to said test probe, said first receiver apparatus to receive and process said test signal; and

indication means responsive to the processing of said test signal to provide an indication of the predictable result if said first receiver apparatus is functioning properly.

2. A system for receiving energy, said system having a receiver apparatus coupled to an antenna capable of radiating and receiving energy, wherein the improvement comprises:

an antenna test probe capable of radiating and receiving energy, said test probe being positioned in close proximity to said antenna and within the field of radiation of said antenna;

test means arranged to apply a test signal having predetermined information to provide a predictable result to said test probe, said test means comprises a signal generating means arranged to provide a first signal having a first fixed frequency to a variable phase shift means, said phase shift means arranged to vary the phase of said first signal;

a second signal generating means arranged to generate a second signal having a second fixed frequency which is greater than said first fixed frequency, said second signal generating means arranged to receive said first signal from said phase shifter and modulate said second signal thereby, the phase difference between said first signal and said second signal providing compass directional information, means for combining said second signal with said first signal; and

a third signal generating means capable of producing a third signal having a third frequency greater than said first or second frequency, said third signal generating means arranged to receive said combined signal and modulate said third signal thereby and apply said modulated signal to said test probe, said modulated signal being said test signal, and said receiver apparatus to receive and process said test signal; and

indication means responsive to the processing of said test signal to provide an indication of said predetermined compass directional information if said receiver apparatus is functioning properly.

3. A system for transmitting and receiving energy for measuring the distance between the transmitting source and a fixed reference station, said system having a first transmitter apparatus and first receiver apparatus with said transmitter means arranged to transmit an r-f carrier signal modulated by a first signal having prearranged pulse pattern formation from an antenna to a remote ground station and said receiver means arranged to receive and process said first signal retransmitted from said ground station, said receiver means capable of measuring the time elapsed from the transmission to the reception of said first signal thereby providing an indication of the distance, said first transmitter and first receiver apparatus coupled to an antenna capable of radiating and receiving energy, wherein the improvement comPrises:

an antenna test probe capable of radiating and receiving energy;

said test probe being positioned in close proximity to said antenna and within the field of radiation of said antenna;

test means arranged to receive said r-f carrier modulated signal from said test probe, said test means having means to detect said first signal with said prearranged pulse pattern, said detector means being arranged to couple said first signal to discrimination circuit means, said discrimination circuit means being arranged to couple said first signal if said first signal comprises the prearranged pulse pattern formation to a delay means, said delay means couples said first signal to a signal generating means after a predetermined length of time, said signal means generating means having a frequency equal to the r-f carrier frequency, said signal generating means combining said first signal with said carrier frequency signal, said signal generating means arranged to couple said combined signal to said distance measuring receiver means for processing; and

indication means responsive to the processing of said combined signal to provide an indication of said predetermined delay of said test means if said distance measuring means is functioning properly.

4. A system for transmitting and receiving energy, said system having a first transmitter and a first receiver apparatus coupled to an antenna capable of radiating and receiving energy, wherein the improvement comprises:

an antenna test probe capable of radiating and receiving energy, said test probe being positioned in close proximity to said antenna and within the field of radiation of said antenna;

a test system coupled to said test probe, said test system having means to produce a first signal having a series of pulses, said first signal being coupled to a signal delay means, said delay means being constructed so as to arrange said series of pulses in a predetermined time relationship, signal generator means arranged to produce a second signal having a frequency equal to the r-f carrier frequency of a transponder apparatus, said signal generator means so constructed as to modulate said second signal with said first signal from said delay line, means for coupling said modulated signal to said transponder apparatus for processing;

said transponder apparatus comprising transmitter and receiver means, said receiver means arranged to receive said modulated signal and to generate a response signal having a series of pulses, the time relationship between said pulses being determined by the time relationship between the pulses of said first signal from said delay line, said transponder receiving means arranged to couple said response signal to said transponder transmitting means for transmission from said antenna, said test system arranged to receive said response signal from said test probe, said test system further comprising signal detection means coupled to said antenna test probe, said detection means so constructed as to produce a series of pulses separated by a time relationship equal to the time relationship present in said transponder response signal, and discrimination circuit means arranged to receive said series of pulses, said discrimination means so constructed as to produce an output signal if the predetermined time relationship between the pulses of said response signal is present; and

indication means responsive to the processing of said response signal having a series of pulses if said transponder apparatus is functioning properly.