Patent US3855533A successfully refreshed from Google Patents.
US3855533A
Expired / Lapsed
US
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System including a transmitter and a receiver for the transmission of binary signals located in periodical clock intervals
Assignee: US Philips Corp
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Filing: 1973-06-01
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Granted: 1974-12-17
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Expires: 1993-06-01
Abstract
Abstract A system for carrier synchronization in a multi-phase transmission system of synchronous pulse signals in which the multi-phase modulator at the transmitter end and the multi-phase demodulator at the receiver end are provided with orthogonal modulators. In order to recover the carrier at the recover end in the correct phase position under all circumstances while avoiding phase uncertainties, a clock interval is reserved for the transmission of a synchronizing signal which is transmitted at the transmitter end through a first channel of the orthogonal modulator while simultaneously the second channel of the orthogonal modulator is interrupted. For the local carrier recovery the receiver comprises a phase stabilization channel connected to the output of the modulator in the receiver channel corresponding to the second transmission channel, which stabilization channel incorporates a blocking circuit which for the purpose of phase stabilization is released by a switching signal at the synchronizing intervals originating from a synchronizing interval selector which for the purpose of selecting the synchronizing intervals of lower signal level is fed by the received phasemodulated oscillations.
Inventors
- 👤 A Schueli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:27
CPC Classifications
H; H04; H04L; H04L5/00; H04L5/02; H04L5/12
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
395 words
A system of the type including a transmitter and a receiver for the transmission of binary pulse signals located in periodic intervals by means of phase modulation, comprising at the transmitter end a phase modulator provided with at least two parallel-arranged channels on an input side thereof, each channel incorporating a modulator, a combination device, and with a common carrier oscillator which feeds the two modulators with carrier oscillations which are mutually shifted 90* in phase, the outputs of the two modulators being combined in the combination device for transmission through a transmission path, while the receiver includes a phase demodulator which is provided with at least two parallel-arranged channels connected on the input side to the transmission path and each incorporating a modulator, and with an arrangement for local carrier recovery which is stabilized on the transmitter carrier oscillations for demodulation of the transmitted binary pulse signals and which feeds the two modulators with carrier oscillations which are mutually shiftEd 90* in phase, the pulse signals derived from each of the outputs of the two modulators being applied through a pulse regenerator to a user, the improvement wherein a synchronizing interval having a duration of at least one clock interval is reserved for phase stabilization in the rhythm of a periodic cycle period corresponding to an integral number of clock intervals, a synchronizing signal generator being connected at a transmitter end to the modulator in the first of the two transmission channels, said generator comprising means for applying a predetermined pulse signal as a synchronizing signal to the input of the modulator incorporated in said channel during the synchronizing intervals, the second of the two channels incorporating an interruptor switch means connected to said synchronizing signal generator for interrupting the second transmission channel at the instants of the synchronizing intervals, while in the receiver the arrangement for local carrier recovery comprises blocking arrangement means for selectively phase reversing the received carrier signal, a synchronizing interval selection means for selecting the synchronizing intervals of a lower signal level, a phase stabilization channel means for connecting the output of the modulator in the receiver channel corresponding to the second transmission channel to the blocking arrangment which for the purpose of phase stabilization is released by a switching signal at synchronizing intervals originating from the synchronizing interval selector means which is fed by the received phasemodulated oscillations.
Claim 2
Independent Claim
395 words
A system of the type including a transmitter and a receiver for the transmission of binary pulse signals located in periodic intervals by means of phase modulation, comprising at the transmitter end a phase modulator provided with at least two parallel-arranged channels on an input side thereof, each channel incorporating a modulator, a combination device, and with a common carrier oscillator which feeds the two modulators with carrier oscillations which are mutually shifted 90* in phase, the outputs of the two modulators being combined in the combination device for transmission through a transmission path, while the receiver includes a phase demodulator which is provided with at least two parallel-arranged channels connected on the input side to the transmission path and each incorporating a modulator, and with an arrangement for local carrier recovery which is stabilized on the transmitter carrier oscillations for demodulation of the transmitted binary pulse signals and which feeds the two modulators with carrier oscillations which are mutually shiftEd 90* in phase, the pulse signals derived from each of the outputs of the two modulators being applied through a pulse regenerator to a user, the improvement wherein a synchronizing interval having a duration of at least one clock interval is reserved for phase stabilization in the rhythm of a periodic cycle period corresponding to an integral number of clock intervals, a synchronizing signal generator being connected at a transmitter end to the modulator in the first of the two transmission channels, said generator comprising means for applying a predetermined pulse signal as a synchronizing signal to the input of the modulator incorporated in said channel during the synchronizing intervals, the second of the two channels incorporating an interruptor switch means connected to said synchronizing signal generator for interrupting the second transmission channel at the instants of the synchronizing intervals, while in the receiver the arrangement for local carrier recovery comprises blocking arrangement means for selectively phase reversing the received carrier signal, a synchronizing interval selection means for selecting the synchronizing intervals of a lower signal level, a phase stabilization channel means for connecting the output of the modulator in the receiver channel corresponding to the second transmission channel to the blocking arrangment which for the purpose of phase stabilization is released by a switching signal at synchronizing intervals originating from the synchronizing interval selector means which is fed by the received phasemodulated oscillations.
Claim 3
Dependent Claim
147 words
A system as claimed in claim 1 in which each of the two transmission channels is fed by an information pulse source, further comprising an intermediate store wherein each of the transmission channels is connected to a shift register and to the information pulse sources, the shift registers being connected to the transmission channel and the information pulse source and being mutually coupled by means of one of the intermediate stores which in the rhythm of the periodic cycle period writes the contents of the shift register connected to the information pulse source in the shift register connected to the transmission channel the latter shift register having an additional shift register element to which the synchronizing signal generator is coupled, while both the shift register connected to the transmission channel and the shift register connected to the information pulse source is completely shifted during each cycle period.
Claim 4
Dependent Claim
32 words
A system as claimed in claim 2, wherein the synchronizing signal generator is constituted by providing the intermediate store with an additional storage element and by connecting a direct voltage source thereto.
Claim 5
Dependent Claim
38 words
A system as claimed in claim 1, wherein the interruptor switch in the second transmission channel is connected to a switching signal generator which is controlled by the cycle frequency and the clock frequency of the transmitted pulses.
Claim 6
Dependent Claim
67 words
A system as claimed in claim 1, wherein an electronic switch is incorporated between the shift register connected to the first transmission channel and the modulator incorporated in said channel, which switch is controlled by the same switching signal as that of the interruptor switch in the second transmission channel and applies a synchronizing signal through an attenuator to the said modulator in the first transmission channel.
Claim 7
Dependent Claim
40 words
A system as claimed in claim 1, wherein the synchronizing interval selector is constituted by an amplitude detector fed by the received pre-modulated oscillations and followed by a subsequent amplitude filter selecting the synchronizing intervals of a lower signal level.
Claim 8
Dependent Claim
27 words
A system as claimed in claim 6, wherein the amplitude detector in the synchronizing interval selector is constituted by an amplitude detector having a quadratic detection characteristic.
Claim 9
Dependent Claim
80 words
A system as claimed in claim 1, provided with an arrangement for local clock signal recovery, wherein the amplitUde filter is constituted by a phase control loop, the recovered clock signals being applied to a phase control circuit while the selected clock signal intervals are derived from its output which intervals are compared in a phase detector with the output signal from the amplitude detector for generating a phase control signal which controls the phase control circuit through a comparator.
Claim 10
Dependent Claim
80 words
A system as claimed in claim 1, wherein the blocking circuit in the phase stabilization channel of the arrangement for local carrier recovery is constituted by a comparator which is also fed by the output signal from the modulator in the receiver channel corresponding to the second transmission channel for the purpose of controlling a phase control circuit to whose input a locally generated carrier is applied and whose output is connected to the modulators in the two receiver channels.
Claim 11
Dependent Claim
64 words
A system as claimed in claim 1, provided with an arrangement for local clock signal recovery, wherein the switching signal for the blocking arrangement in the phase stabilization channel of the arrangement for local carrier recovery is derived from an AND-gate which is fed by the output signals from the synchronizing interval selector as well as from the arrangement for local clock signal recovery.
Claim 12
Dependent Claim
131 words
An arrangement as claimed in claim 1, wherein the pulse regenerators as well as the users in each of the two receiver channels are connected to a shift register and that said shift registers are mutually coupled by means of an intermediate store which in the rhythm of the switching pulses derived from the synchronizing interval selector write the contents of the shift register connected to the pulse regenerator in the register connected to the user, while the contents of the shift register connected to the pulse regenerator are shifted by the clock signals from an arrangement for local clock signal recovery and the contents of the shift register connected to the user are shifted by clock pulses corresponding to the clock pulses of the information pulses at the transmitter end.
Claim 13
Dependent Claim
62 words
A system as claimed in claim 1, adapted for parallel transmission, wherein the phase-modulated output signals are modulated in a modulator by an envelope signal having sinusoidal transitions of clock frequency, while for the local clock signal recovery at the receiver end a local clock oscillator is incorporated in a phase control loop which oscillator is synchronized by the detected envelope signal.
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) | 1977-12-16 | 1978-06-17 | 1978-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-16 | 1982-06-17 | 1982-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-16 | 1986-06-17 | 1986-12-17 | $7700.00 | Window Closed / Lapsed |