US3716859A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Time multiplexer for high prf pulse doppler radar
Assignee: Individual
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Filing: 1970-10-27
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Granted: 1973-02-13
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Expires: 1990-10-27
Abstract
Abstract A digital time multiplexer for use in combination with a high PRF range gated pulse doppler radar which eliminates the need for a doppler filter bank for each range gated receiver in the system. The outputs of n range gated receivers are respectively sampled at the Nyquist rate or faster, converted into a digital signal, and fed into a memory unit on a time shared basis. The data is then sequentially read out of the storage on a per receiver basis into a single doppler filter bank for spectral analysis of the doppler band.
Inventors
- 👤 W Jones
- 👤 R Hendrix
- 👤 W Webb
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:08
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/02; G01S13/50; G01S13/58; G01S13/64
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
239 words
A digital time multiplexer for converting a plurality of pulse doppler radar receiver output CW signals which appear simultaneously in a pulse doppler radar system into a corresponding plurality of sequential signals for analysis by a single doppler filter bank, comprising, in combination: a synchronizer circuit providing outputs comprising time related control signals; circuits means coupled to and operated by said synchronizer for selectively sampling all of said plurality of CW signals; a plurality of signal output lines coupled from said circuit means; first signal converter means coupled to each of said plurality of signal output lines generating a digital representation of the respective CW signal appearing on said plurality of output lines; a digital memory coupled to and operated by said synchronizer and adapted to temporarily store said digital representations in a predetermined order; a multiplexer circuit coupled between said first signal converter means and said memory and operated by said synchronizer for selectively coupling said digital representations into said memory on a time shared basis, said synchronizer then effecting a predetermined sequential read-out of said digital representations; second signal converter means coupled to said memory for reconverting said digital representations in sequential timed relationship into reconstructed representations of said receiver output CW signals; and means coupling said second signal converter means to said doppler filter bank wherein said reconstructed output CW signals appearing in sequential timed relation are fed thereto for spectral analysis of the doppler band.
Claim 2
Dependent Claim
239 words
A digital time multiplexer for converting a plurality of pulse doppler radar receiver output CW signals which appear simultaneously in a pulse doppler radar system into a corresponding plurality of sequential signals for analysis by a single doppler filter bank, comprising, in combination: a synchronizer circuit providing outputs comprising time related control signals; circuits means coupled to and operated by said synchronizer for selectively sampling all of said plurality of CW signals; a plurality of signal output lines coupled from said circuit means; first signal converter means coupled to each of said plurality of signal output lines generating a digital representation of the respective CW signal appearing on said plurality of output lines; a digital memory coupled to and operated by said synchronizer and adapted to temporarily store said digital representations in a predetermined order; a multiplexer circuit coupled between said first signal converter means and said memory and operated by said synchronizer for selectively coupling said digital representations into said memory on a time shared basis, said synchronizer then effecting a predetermined sequential read-out of said digital representations; second signal converter means coupled to said memory for reconverting said digital representations in sequential timed relationship into reconstructed representations of said receiver output CW signals; and means coupling said second signal converter means to said doppler filter bank wherein said reconstructed output CW signals appearing in sequential timed relation are fed thereto for spectral analysis of the doppler band.
Claim 3
Dependent Claim
239 words
A digital time multiplexer for converting a plurality of pulse doppler radar receiver output CW signals which appear simultaneously in a pulse doppler radar system into a corresponding plurality of sequential signals for analysis by a single doppler filter bank, comprising, in combination: a synchronizer circuit providing outputs comprising time related control signals; circuits means coupled to and operated by said synchronizer for selectively sampling all of said plurality of CW signals; a plurality of signal output lines coupled from said circuit means; first signal converter means coupled to each of said plurality of signal output lines generating a digital representation of the respective CW signal appearing on said plurality of output lines; a digital memory coupled to and operated by said synchronizer and adapted to temporarily store said digital representations in a predetermined order; a multiplexer circuit coupled between said first signal converter means and said memory and operated by said synchronizer for selectively coupling said digital representations into said memory on a time shared basis, said synchronizer then effecting a predetermined sequential read-out of said digital representations; second signal converter means coupled to said memory for reconverting said digital representations in sequential timed relationship into reconstructed representations of said receiver output CW signals; and means coupling said second signal converter means to said doppler filter bank wherein said reconstructed output CW signals appearing in sequential timed relation are fed thereto for spectral analysis of the doppler band.
Claim 4
Dependent Claim
239 words
A digital time multiplexer for converting a plurality of pulse doppler radar receiver output CW signals which appear simultaneously in a pulse doppler radar system into a corresponding plurality of sequential signals for analysis by a single doppler filter bank, comprising, in combination: a synchronizer circuit providing outputs comprising time related control signals; circuits means coupled to and operated by said synchronizer for selectively sampling all of said plurality of CW signals; a plurality of signal output lines coupled from said circuit means; first signal converter means coupled to each of said plurality of signal output lines generating a digital representation of the respective CW signal appearing on said plurality of output lines; a digital memory coupled to and operated by said synchronizer and adapted to temporarily store said digital representations in a predetermined order; a multiplexer circuit coupled between said first signal converter means and said memory and operated by said synchronizer for selectively coupling said digital representations into said memory on a time shared basis, said synchronizer then effecting a predetermined sequential read-out of said digital representations; second signal converter means coupled to said memory for reconverting said digital representations in sequential timed relationship into reconstructed representations of said receiver output CW signals; and means coupling said second signal converter means to said doppler filter bank wherein said reconstructed output CW signals appearing in sequential timed relation are fed thereto for spectral analysis of the doppler band.
Claim 5
Dependent Claim
17 words
The invention as defined by claim 1 wherein said first signal converter means comprises analog-to-digital converter means.
Claim 6
Dependent Claim
17 words
The invention as defined by claim 2 wherein said second signal converter means comprises digital-to-analog converter means.
Claim 7
Dependent Claim
60 words
The invention as defined by claim 3 wherein said digital memory comprises a first and a second memory unit, and wherein one memory unit is operable to have digital data read into it during one time interval and the other memory unit is operable to read out data during said time interval of data stored during a previous time interval.
Claim 8
Dependent Claim
30 words
The invention as defined by claim 4 wherein said second signal conversion means comprises a first and a second digital-to-analog converter respectively coupled to said first and second memory unit.
Claim 9
Dependent Claim
90 words
The iNvention as defined by claim 5 and wherein said means coupling said first and second digital-to-analog converters to said doppler filter bank includes switch means coupled between the respective outputs of said first and second digital-to-analog converter and said doppler filter bank, said switch means being operated by a control signal applied from said synchronizer circuit for coupling reconstructed representations of said CW signals from said first and second digital-to-analog converters to said doppler filter bank during the respective read-out time interval of said first and second memory unit.
Claim 10
Dependent Claim
24 words
The invention as defined by claim 6 and additionally including filter and amplifier means coupled between said switch means and said doppler filter bank.
Claim 11
Dependent Claim
66 words
The invention as defined by claim 1 wherein said first signal converter means comprises m analog-to-digital converters for n radar receiver channels, where m is determined by the sampling rate of said circuit means and the maximum operating speed of said analog-to-digital converters and n is determined by the minimum PRF of said pulse doppler radar system and the pulse width of the radiated radar signals.
Claim 12
Dependent Claim
23 words
The invention as defined by claim 8 wherein said pulsed doppler radar system additionally includes means for transmitting a plurality of PRFs sequentially.
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) | 1976-02-13 | 1976-08-14 | 1977-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-13 | 1980-08-14 | 1981-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-13 | 1984-08-14 | 1985-02-13 | $7700.00 | Window Closed / Lapsed |