US3121871A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direction finding system
Assignee: Servo Corp of America
•
Filing: 1962-02-27
•
Granted: 1964-02-18
•
Expires: 1982-02-27
Abstract
No abstract record available.
Inventors
- 👤 John M Beukers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:21
CPC Classifications
G; G01; G01S; G01S3/00; G01S3/02; G01S3/14; G01S3/52; G01S3/54
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
150 words
A PROCESS FOR DETERMINING THE BEARING OF A CARRIER WAVE SIGNAL COMPRISING THE STEPS OF: RECEIVING SAID CARRIER WAVE BY AN EFFECTIVELY REVOLVING ANTENNA TO PRODUCE A PHASE MODULATED CARRIER SIGNAL, THE PATH OF REVOLUTION HAVING A DIAMETER OF ONE WAVELENGTH OR MORE, PRODUCING A LOW FREQUENCY COMPARISON SIGNAL IN ACCORDANCE WITH THE PERIOD OF THE REVOLVING ANTENNA, SIMULTANEOUSLY RECEIVING SAID CARRIER SIGNAL AT A STATIONARY REFERENCE STATION TO PRODUCE A REFERENCE SIGNAL, REDUCING THE FREQUENCY OF SAID PHASE MODULATED CARRIER SIGNAL AND SAID REFERENCE SIGNAL BY RESPECTIVE AMOUNTS WHICH DIFFER FROM EACH OTHER BY A FREQUENCY GENERALLY IN THE AUDIO LOW FREQUENCY RANGE, AMPLITUDE LIMITING BOTH SIGNALS AND THEREAFTER MIXING SAID SIGNALS, WHEREBY A LOW FREQUENCY SIGNAL CARRYING THE BEARING INFORMATION IS PRODUCED BY SAID MIXING, FREQUENCY DISCRIMINATING SAID PHASE MODULATED CARRIER WAVE AND COMPARING SUCH SIGNAL WITH SAID COMPARISON SIGNAL TO DETERMINE THE BEARING OF SAID CARRIER SIGNAL.
References Cited (Backward Citations)
US2276565A
Cited
US2860336A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-02-17 | 1967-08-19 | 1968-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-02-17 | 1971-08-19 | 1972-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-02-17 | 1975-08-19 | 1976-02-18 | $7700.00 | Window Closed / Lapsed |