US4143376A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for sampling tacan signal envelope
Assignee: International Telephone and Telegraph Corp
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Filing: 1977-10-11
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Granted: 1979-03-06
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Expires: 1997-10-11
Abstract
Abstract This invention relates to a method for supplying samples of the received signal envelope in airborne Tacan equipment to the airborne bearing circuitry. During the DME search phase, the airborne DME equipment searches for only those replies which have been received in response to the airborne equipment's own interrogations. After locking onto its own replies, said replies form the samples of the received signal envelope which are applied to a phase locked oscillator, the output of which is coupled to the bearing circuitry both before and after phase shifting. As a result, the airborne receiver duty cycle for Tacan functions is greatly reduced.
Inventors
- 👤 Maurice L. J. Jezo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:06
CPC Classifications
G; G01; G01S; G01S1/00; G01S1/02; G01S1/08; G01S1/44; G01S1/46; G01S13/00; G01S13/74; G01S13/76; G01S13/78; G01S13/785; G01S13/787
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
119 words
An improved method for providing input signal information to the bearing circuits of Tacan airborne equipment of the type which generates interrogation signals which are received by a ground beacon, which in turn transmits to the airborne equipment reply signals in response to the interrogation signals, and wherein samples of the received signal envelope trigger a phase locked oscillator in the airborne equipment, the output of said phase locked oscillator being applied to the airborne bearing circuitry both before and after phase shifting, wherein the improvement comprises: detecting those reply signals which were generated by said beacon in response to interrogation by said airborne equipment; and applying said detected reply signals as said samples to said phase locked oscillator.
Claim 2
Dependent Claim
119 words
An improved method for providing input signal information to the bearing circuits of Tacan airborne equipment of the type which generates interrogation signals which are received by a ground beacon, which in turn transmits to the airborne equipment reply signals in response to the interrogation signals, and wherein samples of the received signal envelope trigger a phase locked oscillator in the airborne equipment, the output of said phase locked oscillator being applied to the airborne bearing circuitry both before and after phase shifting, wherein the improvement comprises: detecting those reply signals which were generated by said beacon in response to interrogation by said airborne equipment; and applying said detected reply signals as said samples to said phase locked oscillator.
Claim 3
Dependent Claim
30 words
A method according to claim 1 wherein said detecting includes generating a gate signal at preselected times during which reply signals responsive to the airborne equipment's own interrogations are expected.
Claim 4
Dependent Claim
27 words
A method according to claim 2 wherein said detecting further includes applying the received reply signals to a gate and enabling said gate during said preselected times.
References Cited (Backward Citations)
US3167759A
Cited
US3836864A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-05 | 1982-09-04 | 1983-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-05 | 1986-09-04 | 1987-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-05 | 1990-09-04 | 1991-03-06 | $7700.00 | Window Closed / Lapsed |