GB1368926A - Radio direction-finding apparatus - Google Patents
Radio direction-finding apparatusInfo
- Publication number
- GB1368926A GB1368926A GB1830573A GB1830573A GB1368926A GB 1368926 A GB1368926 A GB 1368926A GB 1830573 A GB1830573 A GB 1830573A GB 1830573 A GB1830573 A GB 1830573A GB 1368926 A GB1368926 A GB 1368926A
- Authority
- GB
- United Kingdom
- Prior art keywords
- signal
- receiver
- phase
- gate
- aerial
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S3/00—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
- G01S3/02—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using radio waves
- G01S3/14—Systems for determining direction or deviation from predetermined direction
- G01S3/46—Systems for determining direction or deviation from predetermined direction using antennas spaced apart and measuring phase or time difference between signals therefrom, i.e. path-difference systems
- G01S3/48—Systems for determining direction or deviation from predetermined direction using antennas spaced apart and measuring phase or time difference between signals therefrom, i.e. path-difference systems the waves arriving at the antennas being continuous or intermittent and the phase difference of signals derived therefrom being measured
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Variable-Direction Aerials And Aerial Arrays (AREA)
Abstract
1368926 Radio direction-finding THOMSONCSF 16 April 1973 [17 April 1972] 18305/73 Heading H4D Direction finding apparatus comprises first and second spaced aerials, an f.m. receiver, a switching arrangement, including a switch coupled to the receiver input, and control means having an output coupled to this switch, for alternately coupling said receiver to the aerials, so that at the receiver input the signal from one aerial is gradually substituted by the signal from the other, a device being provided to measure the phase shift between the receiver output component having the same frequency as the aerial switching frequency. A diode switch 3, controlled by oscillator 5 alternately connects aerials A, B to f.m. receiver 4, the change over from A to B being gradual. In Fig. 3 (not shown) the resulting input to receiver 4 is illustrated as waveform b giving the phase of the receiver input signal with respect to the signal from aerial A (the dotted waveforms correspond to the situation when the incoming radio waves are of opposite sense). As the aerials are spaced their signals are out of phase, the phase difference being dependent upon the incoming direction of the radio waves X, Y (Fig. 1, not shown). The gradual change-over from aerial A to B produces a signal of gradually changing phase to be applied to the receiver discriminator. The discriminator produces an output signal U (Fig. 3) of magnitude corresponding to the phase difference. The signal is applied to a low pass filter 6 giving the fundamental of the output signal which is amplified in logarithmic amplifier 7. The signal e (Fig. 3, not shown) is passed to a synchronous detector 8 which gives the phase of the signal with respect to the switching waveform from oscillator 5. The phase difference (Œ#/2) gives the sense of the incoming waves. The information relating to phase difference and magnitude of the signal from the receiver is then passed to an indicating instrument 9 giving the magnitude and sense of the angle of incidence of the incoming waves. The information is passed to indicator 9 via a gate 21. Bandpass filters 19, 20 detect correct operation of oscillator 5 and noise levels respectively. If the output of filter 19 is sufficiently high and that of filter 20 is sufficiently low, gate 21 allows application of the information to indicator 9. A trigger circuit 10 having a threshold removes any small erratic fluctuations corresponding to when the angle of wave incidence is 0. Circuit 10 produces signals of positive, 0 or negative value depending on whether the waves arrive from the right, on the central axis or from the left of the antennas. Circuits 11, 12, 13 generating the Morse code for letter U, a continuous signal or Morse code for D respectively are correspondingly activated so that OR gate 14 activates AND gate 17 accordingly. An audio oscillator 15, via an adjustable attenuator 16, supplies a signal, modulated by gate 17 the headphone 18 thus indicating the sense of direction of the incoming waves to an operator. In addition, attenuator 16 is controlled by the signal amplitude from circuit 21 so that the volume of the signals in headphone 18 indicates the magnitude of the incidence angle.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR7213440A FR2180449B1 (en) | 1972-04-17 | 1972-04-17 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1368926A true GB1368926A (en) | 1974-10-02 |
Family
ID=9096982
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB1830573A Expired GB1368926A (en) | 1972-04-17 | 1973-04-16 | Radio direction-finding apparatus |
Country Status (4)
Country | Link |
---|---|
DE (1) | DE2319241A1 (en) |
FR (1) | FR2180449B1 (en) |
GB (1) | GB1368926A (en) |
IT (1) | IT980226B (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109375155A (en) * | 2018-11-28 | 2019-02-22 | 成都中星世通电子科技有限公司 | A kind of radio signal monitoring and direction-finding method and processor based on sense of hearing mapping |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2433075A1 (en) * | 1978-08-08 | 1980-03-07 | Herstad Oystein | Offshore oil rig helicopter landing platform - has grill structure resting by distancing frame on base with fire-fighting foam-producing piping in gap (NO 18.09.78) |
FR2617981B1 (en) * | 1987-07-07 | 1989-06-09 | Thomson Csf | METHOD AND DEVICE FOR PROTECTING AGAINST INTERFERENCE IN A RADIO STATION COMPRISING SEVERAL SWITCHABLE ANTENNAS AND THEIR USE IN THE PRODUCTION OF RADIOGONIOMETERS |
-
1972
- 1972-04-17 FR FR7213440A patent/FR2180449B1/fr not_active Expired
-
1973
- 1973-04-16 DE DE19732319241 patent/DE2319241A1/en active Pending
- 1973-04-16 IT IT4946673A patent/IT980226B/en active
- 1973-04-16 GB GB1830573A patent/GB1368926A/en not_active Expired
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109375155A (en) * | 2018-11-28 | 2019-02-22 | 成都中星世通电子科技有限公司 | A kind of radio signal monitoring and direction-finding method and processor based on sense of hearing mapping |
Also Published As
Publication number | Publication date |
---|---|
IT980226B (en) | 1974-09-30 |
FR2180449A1 (en) | 1973-11-30 |
FR2180449B1 (en) | 1976-10-29 |
DE2319241A1 (en) | 1973-10-25 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed | ||
PLNP | Patent lapsed through nonpayment of renewal fees |