METHOD AND APPARATUS FOR FINDING THE DIRECTION OF SIGNALS

• US 3,710,332 A
• Filed: 04/21/1966
• Issued: 01/09/1973
• Est. Priority Date: 04/21/1966
• Status: Expired due to Term

• Current Assignee: Alfred Schief, Horst Tischner, Hugo Baur
• Original Assignee: Alfred Schief, Horst Tischner, Hugo Baur
• Inventors: Tischner, Horst, Schief, Alfred, Baur, Hugo
• Primary Examiner(s): Borchelt, Benjamin A.
• Assistant Examiner(s): Berger, Richard E.
• Application Number:
  US04/545,801
• Time in Patent Office: 2,455 Days
• Field of Search: 343/100.7,113,119
• US Class Current: 342/378
• CPC Class Codes: G01S 3/14 Systems for determining direction or deviation from predetermined direction aerial arrangements for changing or varying the orientation or the shape of the directional pattern H01Q3/00; combinations of different interacting aerial units for giving a desired directional characteristic H01Q21/29; aerials or aerial systems providing at least two radiation patterns H01Q25/00

Abstract

Two directional receivers and a non-directional receiver produce voltages when receiving a main signal and interfering signal. The voltages are cross-correlated so that the resultant voltages are functions of the angle between the direction of the main signal and a reference line, and can be evaluated to determine the direction of the main signal.

Claims

1. A method for determining the direction of the signals of a signal source in the presence of interfering signals, comprising the steps of receiving the signals of the signal source and the interference signals by receivers having different directional characteristics and producing voltages;

cross-correlating the voltages produced by said receivers to produce voltages which are functions of the angle between said direction and a reference line defined by said directional receivers; and

evaluating said functions to find said angle and said direction of the signals of said signal source.

2. The method according to claim 1 including receiving said signals by directional and non-directional receivers;

and cross-correlating the voltage produced by a directional receiver with the voltage produced by a nondirectional receiver to produce said composite voltages.

3. The method according to claim 2 including receiving the signals by two directional receivers set at an angle of 90* and by one non-directional receiver.

4. The method according to claim 2 including sequentially storing each of said composite voltages at time intervals;

and sequentially picking up the stored composite voltages at time intervals.

5. The method according to claim 3 and including suppressing components of said composite voltages produced by said interfering signals;

and wherein said evaluating includes supplying the two resultant composite voltages to the plates of an oscillograph so that said oscillograph indicates said angle between said direction and said reference line.

6. The method according to claim 3 including the steps of storing each of said composite voltages;

picking up said stored voltages; and

wherein said evaluating includes supplying said composite voltages to the plates of an oscillograph so that the same indicates said angle between said direction and said reference line.

7. An apparatus for determining the direction of signals of a signal source in the presence of interfering signals, comprising, in combination, a plurality of receivers including two directional receivers set at an angle to each other;

correlator means connected with at least one pair of said receivers for correlating voltages received from the same so as to produce composite voltages which are different functions of the angle between said direction and a reference line defIned by said directional receivers; and

evaluating means connected with said correlator means for receiving said composite voltages and controlled by the same to indicate said last-mentioned angle and said direction.

8. The apparatus according to claim 7, wherein said plurality of receivers also includes a non-directional receiver;

and wherein said correlator means include a pair of correlators respectively connected with one and the other of said directional receivers, and with said non-directional receiver.

9. The apparatus according to claim 7, wherein said evaluating means include storage means connected with said correlator means for receiving said correlated voltages, and indicator means controlled by said composite voltages to indicate said last-mentioned angle and said direction.

10. The apparatus according to claim 7, wherein said plurality of receivers also includes a non-directional receiver;

wherein said correlator means include a pair of correlators respectively connected with one and the other of said directional receivers, and with said non-directional receiver;

wherein said directional receivers are set at an angle of 90* to each other; and

wherein said evaluating means include storage means for said composite voltages, and an oscillograph controlled by said composite voltages to indicate said last-mentioned angle and said direction.

11. The apparatus according to claim 10 and including means for suppressing in said oscillograph components of said composite voltages produced by said interfering signals.

12. The apparatus according to claim 7, wherein said plurality of receivers includes also a non-directional receiver;

wherein said correlator means are also connected with said non-directional receiver and include multiplication and integration devices, and delay means; and

including storage means for storing said composite voltages; and

wherein said evaluating means are connected with said correlator means and controlled by the stored composite voltages.

13. The apparatus according to claim 12, wherein said delay means are connected with said directional and non-directional receivers.

14. The apparatus according to claim 12, wherein said delay means include a sequential register.

15. The method according to claim 1 including receiving said signals by directional and non-directional receivers;

cross-correlating the voltage produced by a directional receiver with the voltage produced by a non-directional receiver to produce said composite voltages; and

computing, simultaneously with cross-correlating said voltages, the cross-correlation functions for different delay times.

16. The method according to claim 1 including receiving said signals by directional and non-directional receivers;

cross-correlating the voltage produced by a directional receiver with the voltage produced by a non-directional receiver to produce said composite voltages; and

computing, simultaneously with cross-correlating said voltages, the cross-correlation functions for a delay time of zero.

17. The method according to claim 1 including interpolating periodical components of said voltages.

18. The method according to claim 1 including coding of the voltage values before and after correlating said voltages.

19. The method according to claim 1 including expressing voltage values as digits for the purpose of calculations.

20. The method according to claim 1 including storing said composite voltages and evaluating the stored voltages.

21. The method according to claim 1, including the step of positioning said receivers for receiving said signals without differences in the time of travel of the same.

22. An apparatus according to claim 7, wherein said receivers of said plurality of receivers are located adjacent each other for receiving said signals without differences in the time of travel.