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US4008378A
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Multi-radix digital communications system with time-frequency and phase-shift multiplexing
Assignee: NS ELECTRONICS
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Filing: 1975-03-17
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Granted: 1977-02-15
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Expires: 1995-03-17
Abstract
Abstract A communication or data transmission system having one or more transmitters placing input signals in digital pulse form if they are not already in such form, storing and time stretching of such pulses, conversion of the pulses into time-frequency matrix addresses and phase shifting each of a set of RF carriers within given time slots to one of a predetermined number of phase angles during each time frame for transmittal to maximize the number of bits of information that can be transmitted in a given bandwidth and minimizing transmission errors. Receivers connected to the transmitters by a transmission medium, such as a telephone cable, reverse the processing of the transmitters.
Inventors
- 👤 W. Franklin Nance
- 👤 Robert L. Shacklett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:34
CPC Classifications
H; H04; H04J; H04J4/00; H04B; H04B14/00; H04B14/02; H04B14/06; H04B14/066; H04L; H04L27/00; H04L27/10; H04L5/00; H04L5/22; H04L5/26
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
149 words
A frequency-time division multiplexing communication system comprising: a transmitter adapted to receive input signals for transmission and including means establishing successive time frames within each of which the inputs are sampled numerous times to produce binary pulse trains for each frame and phase shift means operated by said binary pulse trains to phase shift predetermined carrier signals at predetermined times in each frame in accordance with the information per frame, a transmission medium connected to the output of said transmitter for transmitting said phase-shifted carriers, and a receiver connected to said transmission medium and including means detecting each carrier phase shift and counting the number of phase-shifted cycles of each carrier in each frame to only identify the phase shift information upon counting of a predetermined number of phase-shifted cycles per frame to minimize noise errors, and means reconstructing the input to said transmitter from said phase shift information.
Claim 2
Dependent Claim
149 words
A frequency-time division multiplexing communication system comprising: a transmitter adapted to receive input signals for transmission and including means establishing successive time frames within each of which the inputs are sampled numerous times to produce binary pulse trains for each frame and phase shift means operated by said binary pulse trains to phase shift predetermined carrier signals at predetermined times in each frame in accordance with the information per frame, a transmission medium connected to the output of said transmitter for transmitting said phase-shifted carriers, and a receiver connected to said transmission medium and including means detecting each carrier phase shift and counting the number of phase-shifted cycles of each carrier in each frame to only identify the phase shift information upon counting of a predetermined number of phase-shifted cycles per frame to minimize noise errors, and means reconstructing the input to said transmitter from said phase shift information.
Claim 3
Dependent Claim
65 words
The system of claim 1 wherein the input is an analog waveform further comprised by said transmitter comprising a pair of tank circuits tuned to oscillate at the frequency of a carrier, means alternately energizing said tank circuits with information in said binary pulse train to thus alternately generate phase-shifted carrier signals, and switch means alternately applying said phase-shifted carrier signals to said transmission medium.
Claim 4
Dependent Claim
91 words
The system of claim 1 further defined by said receiver comprising: a phase-locked loop connected to receive signals from said transmission medium and producing from signals thereon the original carrier without phase shift for retransmission, leading and lagging phase detectors including registers and gate circuits for detecting leading and lagging phase-shifted input carriers, counting means connected to said registers and gate circuits for counting the number of phase-shifted carrier cycles, and logic circuits connected to said counting circuits and to a source of timing signals for reconstructing said binary pulse train.
Claim 5
Dependent Claim
21 words
The system of claim 3 further defined by a demodulator receiving said binary pulse train and producing an analog waveform therefrom.
Claim 6
Dependent Claim
86 words
The system of claim 1 further defined by said receiver having input registers connected to a source of timing signals, interface buffer registers connected to said input registers and adapted for connection to a data source producing a train of digital bits, and means applying an early sample clock signal to said buffer registers for clearing same and a late sample clock signal slightly delayed from the early sample clock signal to said input registers to clear same after the buffer register information is stored therein.
Claim 7
Dependent Claim
130 words
A communication system comprising a transmitter including sampling means adapted to receive input signals and to sample such signals a plurality of times in each of successive time frames and producing binary pulse trains for each time frame, and phase-shifting means operated by said binary pulse trains for phase-shifting predetermined carrier signals of different frequency at predetermined times in each frame in accordance with the information of said binary pulse trains; a transmission medium connected to the output of said transmitter for transmitting said phase-shifted carriers; and a receiver connected to said transmission medium and including means for detecting the phase shift of individual cycles of separate carriers and discriminating against noise signals, and means reconstructing the input to said transmitter from said detected carrier phase shifts at predetermined times.
Claim 8
Dependent Claim
130 words
A communication system comprising a transmitter including sampling means adapted to receive input signals and to sample such signals a plurality of times in each of successive time frames and producing binary pulse trains for each time frame, and phase-shifting means operated by said binary pulse trains for phase-shifting predetermined carrier signals of different frequency at predetermined times in each frame in accordance with the information of said binary pulse trains; a transmission medium connected to the output of said transmitter for transmitting said phase-shifted carriers; and a receiver connected to said transmission medium and including means for detecting the phase shift of individual cycles of separate carriers and discriminating against noise signals, and means reconstructing the input to said transmitter from said detected carrier phase shifts at predetermined times.
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) | 1980-02-15 | 1980-08-16 | 1981-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-15 | 1984-08-16 | 1985-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-15 | 1988-08-16 | 1989-02-15 | $7700.00 | Window Closed / Lapsed |