DIRECTION FINDING RECEIVER

• US 3,626,416 A
• Filed: 04/29/1970
• Issued: 12/07/1971
• Est. Priority Date: 04/29/1970
• Status: Expired due to Term

• Current Assignee: ITT Corporation (ITT, Inc.)
• Original Assignee: Gerald Rabow
• Inventors: Rabow, Gerald
• Primary Examiner(s): Farley, Richard A.
• Assistant Examiner(s): Berger, Richard E.
• Application Number:
  US05/032,952
• Time in Patent Office: 587 Days
• Field of Search: 343/113,113PT 325/361,307
• US Class Current: 342/419
• CPC Class Codes: G01S 3/46 using antennas spaced apart and measuring phase or time difference between signals therefrom, i.e. path-difference systems

Abstract

An antenna having an omnidirectional or a predetermined directional pattern and an earphone are disposed adjacent each of the ears of a human. The antennas are interconnected by a binaural receiver to convert the radio frequency signal received by both the antennas into a pair of audiofrequency signals and preserve in the pair of audiofrequency signals the phase relationship between the received radio frequency signals. This will enable the human'"'"''"'"'s sense of direction, as provided by the characteristics of the human ears, to locate the direction of the radiofrequency signal.

Claims

1. A portable direction finding receiver utilizing the ears of a human and the human'"'"''"'"'s resultant sense of direction to locate the direction of a radio frequency signal source comprising:

a pair of antennas each having a predetermined pattern and disposed adjacent a different one of said ears of said human in communication with said source;

a binaural receiver coupled to said pair of antennas to convert said radio frequency signals received by each of said antennas to a pair of audiofrequency signals and preserve in said audiofrequency signals the phase relationship between said received radio frequency signals; and

a pair of earphones each disposed in a listening relationship with a different one of said ears of said human coupled to said receiver to enable said human to respond to said pair of audiofrequency signals and locatE the direction of said source.

2. A direction-finding receiver according to claim 1, wherein the audio wavelength in air of said pair of audiofrequency signals is equal to the radio frequency wavelength in air of said radio frequency signal.

3. A direction-finding receiver according to claim 1, wherein each of said pair of antennas has an omnidirectional pattern.

4. A direction-finding receiver according to claim 1, wherein each of said pair of antennas has a directional pattern approximating the directional pattern of the associated one of said ears.

5. A direction-finding receiver according to claim 1, wherein said binaural receiver includes a first signal channel including a first mixer means coupled to one of said pair of antennas, a second signal channel including a second mixer means coupled to the other of said pair of antennas, and oscillator means coupled to both said first and second mixer means to provide one of said pair of audiofrequency signals in said first signal channel and the other of said pair of audiofrequency signals in said second signal channel.

6. A direction -finding receiver according to claim 5, wherein the frequency of the output signal of said oscillator means has a value below the value of the frequency of said radio frequency signal.

7. A direction-finding receiver according to claim 6, wherein the value of the frequency of the output signal of said oscillator means is selected relative to the value of frequency of said radio frequency signal to provide a value of frequency for said pair of audiofrequency signals so that the audio wavelength in air of said pair of audiofrequency signals is equal to the radiofrequency wavelength in air of said radio frequency signal.

8. A direction-finding receiver according to claim 5, wherein said binaural receiver further includes an automatic frequency control means to stabilize the value of the frequency of the output signal of said oscillator means.

9. A direction-finding receiver according to claim 8, wherein the value of the stabilized frequency of the output signal of said oscillator means is selected relative to the value of frequency of said radio frequency signal to provide a value of frequency for said pair of audiofrequency signals so that the audio wavelength in air of said pair of audiofrequency signals is equal to the radio frequency wavelength in air of said radio frequency signal.

10. A direction-finding receiver according to claim 5, wherein at least one of said first and second signal channels includes a variable delay means to equalize the inherent circuit delays in each of said first and second signal channels.