US3798648A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High resolution airborne signal processing system
Assignee: Individual
•
Filing: 1972-06-27
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Granted: 1974-03-19
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Expires: 1992-06-27
Abstract
Abstract A two-antenna reception system with fixed-position antennas to receive linearly frequency-modulated signals or linearly position-modulated antennas to receive fixed-frequency signals. The difference frequency generated from the antenna signals represents the angle of arrival with respect to the system baseline. Two such systems with nonparallel baselines yield angular information in space.
Inventors
- 👤 U Lammers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:07
CPC Classifications
G; G01; G01S; G01S3/00; G01S3/02; G01S3/14; G01S3/46; G01S3/465; G01S3/52
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
95 words
A multiple antenna direction finding system comprising: a first and second antenna moving with a known velocity relative to each other for receiving fixed frequency signals from a target; a signal mixing means connected to each antenna for obtaining a difference frequency signal from the output of the first and second antenna; frequency analyzing means for identifying a particular frequency from a spectrum of possible frequencies at the mixer output; means to convert the identified frequency information into angular information; and a calibrated means for displaying one-dimensional directional information operatively connected to the converter means.
Claim 2
Dependent Claim
95 words
A multiple antenna direction finding system comprising: a first and second antenna moving with a known velocity relative to each other for receiving fixed frequency signals from a target; a signal mixing means connected to each antenna for obtaining a difference frequency signal from the output of the first and second antenna; frequency analyzing means for identifying a particular frequency from a spectrum of possible frequencies at the mixer output; means to convert the identified frequency information into angular information; and a calibrated means for displaying one-dimensional directional information operatively connected to the converter means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-18 | 1977-09-17 | 1978-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-18 | 1981-09-17 | 1982-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-18 | 1985-09-17 | 1986-03-19 | $7700.00 | Window Closed / Lapsed |