Patent US3766477A successfully refreshed from Google Patents.
US3766477A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spread spectrum, linear fm communications system
Assignee: Unisys Corp
•
Filing: 1971-12-20
•
Granted: 1973-10-16
•
Expires: 1991-12-20
Abstract
Abstract A pulse compression system comprising a transmitter which provides a maximum number of output signals from a class of linear waveforms in which the number that may be used is a function of the desired cross-talk performance which depends on the signal time-bandwidth product and the FM slope differences between the signals. The transmitter includes a plurality of linear FM generators and associated modulation oscillators to provide the number of different signals desired. A receiver responsive to the number of different transmitted signals includes a corresponding number of mixers and local oscillators coupled to pulse compression filter means having optimum response characteristics matched to the number of signals that are transmitted thereby enabling a significant increase in the number of signals which may be transmitted and received by the disclosed communications system.
Inventors
- 👤 C Cook
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:53
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/69; H04L; H04L27/00; H04L27/10; H04L27/103
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
122 words
A pulse compression communications system including a transmitter and a receiver; said transmitter comprising, a source of triggering pulses, a source of a plurality of frequency swept carrier oscillations providing a plurality of non-synchronous signals within a limited time-frequency region each signal having a different time versus frequency slope characteristic which satisfies a specific cross-talk requirement between signals having adjacent values of time-bandwidth product, means for transmitting said plurality of non-synchronous frequency swept carrier signals; said receiver comprising, means for receiving said transmitted plurality of nonsynchronous frequency swept carrier signals, and pulse compression filter means including a processor for providing a plurality of output pulses; each output pulse corresponding to a selected one of said plurality of transmitted non-synchronous frequency swept signals.
Claim 2
Dependent Claim
122 words
A pulse compression communications system including a transmitter and a receiver; said transmitter comprising, a source of triggering pulses, a source of a plurality of frequency swept carrier oscillations providing a plurality of non-synchronous signals within a limited time-frequency region each signal having a different time versus frequency slope characteristic which satisfies a specific cross-talk requirement between signals having adjacent values of time-bandwidth product, means for transmitting said plurality of non-synchronous frequency swept carrier signals; said receiver comprising, means for receiving said transmitted plurality of nonsynchronous frequency swept carrier signals, and pulse compression filter means including a processor for providing a plurality of output pulses; each output pulse corresponding to a selected one of said plurality of transmitted non-synchronous frequency swept signals.
Claim 3
Dependent Claim
35 words
A pulse compression communications system as described in claim 1 in which said source of a plurality of frequency swept carrier oscillations includes means for providing signals having the same pulse duration and different bandwidths.
Claim 4
Dependent Claim
35 words
A pulse compression communications system as described in claim 1 in which said source of a plurality of frequency swept carrier signals includes means for providing signals having the same bandwidth and different pulse durations.
Claim 5
Dependent Claim
49 words
A pulse compression communications system as described in claim 1 in which said source of a plurality of frequency swept carrier oscillations includes means for providing a plurality of synchronous signals, and said processor for providing a plurality of output pulses includes a processor for providing synchronizing pulse signals.
Claim 6
Dependent Claim
57 words
A pulse compression communications system as described in claim 4 in which said means for providing synchronous signals includes a source of frequency swept carrier oscillations for providing a low energy frequency modulated preamble signal as the synchronizing signal and said processor for providing synchronizing signals includes means which provides a low energy synchronizing preamble pulse signal.
Claim 7
Dependent Claim
169 words
A pulse compression communications system including a transmitter and a receiver; said transmitter comprising, a source of triggering pulses, a plurality of sources of frequency swept carrier oscillations providing a plurality of synchronous signals within a limited time-frequencY region each signal having a different time versus frequency slope characteristic which satisfies a specific cross-talk requirement between signals having adjacent values of time-bandwidth product, a plurality of sinusoidal modulating signals, a plurality of means for angle modulating said frequency swept carrier oscillations with said sinusoidal modulating signals, each of said means coupled to a corresponding one of said plurality of sources of frequency swept carrier oscillation and a corresponding one of said sources of sinusoidal modulating signals, means for simultaneously transmitting said angle modulated carrier oscillations; said receiver comprising means for receiving the transmitted carrier oscillations, and pulse compression filter means including a plurality of processors for providing a plurality of output pulse groups; each output pulse group corresponding to a selected one of said plurality of angle modulated signals.
Claim 8
Dependent Claim
169 words
A pulse compression communications system including a transmitter and a receiver; said transmitter comprising, a source of triggering pulses, a plurality of sources of frequency swept carrier oscillations providing a plurality of synchronous signals within a limited time-frequencY region each signal having a different time versus frequency slope characteristic which satisfies a specific cross-talk requirement between signals having adjacent values of time-bandwidth product, a plurality of sinusoidal modulating signals, a plurality of means for angle modulating said frequency swept carrier oscillations with said sinusoidal modulating signals, each of said means coupled to a corresponding one of said plurality of sources of frequency swept carrier oscillation and a corresponding one of said sources of sinusoidal modulating signals, means for simultaneously transmitting said angle modulated carrier oscillations; said receiver comprising means for receiving the transmitted carrier oscillations, and pulse compression filter means including a plurality of processors for providing a plurality of output pulse groups; each output pulse group corresponding to a selected one of said plurality of angle modulated signals.
Claim 9
Dependent Claim
26 words
A pulse compression communications system as described in claim 6 in which said receiver further includes delay means for interlacing said plurality of output pulse groups.
Claim 10
Dependent Claim
114 words
A pulse communications system as described in claim 6 which further includes a plurality of second sources of frequency swept carrier oscillations in which the sense of the carrier frequency sweep of said second sources is opposite to the sense of the carrier frequency sweep of said first sources of frequency swept carrier oscillations; said receiver further includes means for inverting the frequency sweep sense of both received carrier oscillations, and second pulse compression means including a plurality of second processors for providing a plurality of output pulse groups, the receiver carrier oscillations being applied to the first pulse compression means and the sense-inverted carrier oscillations being applied said second pulse compression filter means.
Claim 11
Dependent Claim
50 words
A pulse compression communications system as described in claim 1 in which said source of a plurality of frequency swept carrier oscillations includes first means for providing signals having the same pulse duration and different bandwidths and second means for providing signals having the same bandwidth and different pulse durations.
Claim 12
Dependent Claim
36 words
A pulse compression communications system as described in claim 1 in which said source of a plurality of frequency swept carrier oscillations includes means for providing signals having the same center frequency with different frequency bandwidths.
Claim 13
Dependent Claim
36 words
A pulse compression communications system as described in claim 1 in which said source of a plurality of frequency swept carrier oscillations includes means for providing signals having different center frequencies and the same frequency bandwidths.
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) | 1976-10-15 | 1977-04-16 | 1977-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-15 | 1981-04-16 | 1981-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-15 | 1985-04-16 | 1985-10-16 | $7700.00 | Window Closed / Lapsed |