US4423505A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cued adaptive canceller
Assignee: Lockheed Martin Tactical Systems Inc
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Filing: 1981-11-23
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Granted: 1983-12-27
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Expires: 2001-11-23
Abstract
Abstract An adaptive canceller construction for cancelling signals received by a radio receiver operating in close proximity to a transmitter having means for extending the usefulness of the device over a wide band of frequencies. The canceller is provided with a memory which will remember the adopted parameter from one time in a given band to the next, so that as a jammer frequency jumps back and forth among several narrow frequency bands, the canceller will jump among a corresponding set of remembered parameters.
Inventors
- 👤 John H. Greig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:14
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/38; H04B1/40; H04B1/50; H04B1/52; H04B1/525; H04K; H04K3/00; H04K3/20; H04K3/28; H04K3/40; H04K3/42; H04K3/45
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
131 words
A cued adaptive canceller for use in conjunction with a radio receiver and a radio transmittor simultaneously operated in close proximity for cancelling reception of transmitted signals comprising: a cancelling loop including a connection to said transmittor to input sample transmitted signals, a phase control an amplitude control and a subtractor; said subtractor connected to an input to said receiver, and a cross correlator having an input of received signals; first and second filters interconnecting the output of said cross correlator and said phase control and said amplitude control, respectively; a parameter multiplexer connected in parallel with each of said filters, and a plurality of capacitors each selectively interconnected in parallel with a respective filter by operation of one of said multiplexers; and control means for governing operation of said multiplexers.
Claim 2
Dependent Claim
131 words
A cued adaptive canceller for use in conjunction with a radio receiver and a radio transmittor simultaneously operated in close proximity for cancelling reception of transmitted signals comprising: a cancelling loop including a connection to said transmittor to input sample transmitted signals, a phase control an amplitude control and a subtractor; said subtractor connected to an input to said receiver, and a cross correlator having an input of received signals; first and second filters interconnecting the output of said cross correlator and said phase control and said amplitude control, respectively; a parameter multiplexer connected in parallel with each of said filters, and a plurality of capacitors each selectively interconnected in parallel with a respective filter by operation of one of said multiplexers; and control means for governing operation of said multiplexers.
Claim 3
Dependent Claim
62 words
A cued adaptive canceller in accordance with claim 1, in combination with a transmitter having selectively interconnectable plural signal sources of varying frequencies, and control means for interconnecting selected ones of said plural signal sources to said transmitter; said first mentioned control means assigning specific frequencies of said plural signal sources to specific individual condensors connected by said first and second multiplexers.
Claim 4
Dependent Claim
64 words
A cued adaptive canceller in accordance with claim 1, further characterized in said first and second filters being of digital type, said canceller further comprising a microprocessor, said canceller filters being implemented in the microprocessor, the filter parameters being stored in computer memory; wherein the output of said cross correlator is digitized and the phase and amplitude of a sample signal is digitally controlled.
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) | 1986-12-26 | 1987-06-27 | 1987-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-26 | 1991-06-27 | 1991-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-26 | 1995-06-27 | 1995-12-27 | $7700.00 | Window Closed / Lapsed |