Receiver having a local oscillator first synchronized to a reference frequency and then to a received signal
First Claim
Patent Images
1. A receiver array for reception and for demodulation of a useful signal with a given carrier frequency, in particular of the radio signal from a time signal transmitter, comprising:
- a signal path structured in accordance with the reception principle of synchronous demodulation;
a controllable oscillator array for generating first and second heterodyne signals, with said first heterodyne signal being fed to a first mixer in said signal path for synchronous demodulation of the useful signal, and with said second heterodyne signal being phase-shifted by π
/2 relative to said first heterodyne signal;
a first control circuit having a stable reference source and a phase detector of a wide reception range for detecting a phase difference between the output signal of said reference source and said first heterodyne signal and generating a first control signal for said oscillator array corresponding to the difference;
a second control circuit for generating a second control signal for said oscillator array for phase synchronization of said first heterodyne signal with the useful signal, said second control circuit comprising a second mixer which is supplied with said useful signal and said second heterodyne signal, and which produces said second control signal at its output; and
;
a switching means for applying said first control signal to the control signal input of said oscillator array during a presynchronization phase, and for applying said second control signal to the control signal input of said oscillator array during a subsequent demodulation phase.
5 Assignments
0 Petitions
Accused Products
Abstract
A receiver array in accordance with the reception principle of synchronous demodulation, in which a controllable oscillator array is pre-synchronized to a set value for the oscillator frequency by a digital first control circuit having a reference frequency source during a pre-synchronization phase, and a heterodyne signal derived from the oscillator frequency is then synchronized with phase locking to the received useful signal by switching the oscillator control input to an analog second control circuit.
-
Citations
19 Claims
-
1. A receiver array for reception and for demodulation of a useful signal with a given carrier frequency, in particular of the radio signal from a time signal transmitter, comprising:
-
a signal path structured in accordance with the reception principle of synchronous demodulation; a controllable oscillator array for generating first and second heterodyne signals, with said first heterodyne signal being fed to a first mixer in said signal path for synchronous demodulation of the useful signal, and with said second heterodyne signal being phase-shifted by π
/2 relative to said first heterodyne signal;a first control circuit having a stable reference source and a phase detector of a wide reception range for detecting a phase difference between the output signal of said reference source and said first heterodyne signal and generating a first control signal for said oscillator array corresponding to the difference; a second control circuit for generating a second control signal for said oscillator array for phase synchronization of said first heterodyne signal with the useful signal, said second control circuit comprising a second mixer which is supplied with said useful signal and said second heterodyne signal, and which produces said second control signal at its output; and
;a switching means for applying said first control signal to the control signal input of said oscillator array during a presynchronization phase, and for applying said second control signal to the control signal input of said oscillator array during a subsequent demodulation phase. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. A receiver for reception and for demodulation of a useful signal with a given carrier frequency, in particular of the radio signal from a time signal transmitter, comprising:
-
a signal path structured in accordanc with the reception principle of synchronous demodulation path including a first mixer for the synchronous demodulation of a useful signal and a frequency selective means including a controllable filter located in front of said first mixer for frequency selection; a controllable oscillator array for generating a first heterodyne signal which is fed to said first mixer for synchronous demodulation of the useful signal in said first mixer; a first control circuit having a stable reference source and a phase detector of a wide reception range for receiving the signal from said reference source and an output signal from said oscillator array and for generating a first control signal for said oscillator array; a second control circuit for generating a second control signal for said oscillator array for phase synchronization of said first heterodyne signal with the useful signal; a switching means for applying said first control signal to the control signal input of said oscillator array during a presynchronization phase, and for applying said second control signal to the control signal input of said oscillator array during a subsequent demodulation phase; and means, connected to said control signal input, for deriving a control signal for said controllable filter from said first and second control signals. - View Dependent Claims (18)
-
-
19. A receiver for reception and for demodulation of a useful signal with a given carrier frequency, in particular of the radio signal from a time signal transmitter, comprising;
-
a signal path structured in accordance with the reception principle of synchronous demodulation; a controllable oscillator array generating a first heterodyne signal for synchronous demodulation of the useful signal in a first mixer disposed in said signal path; a first control circuit having a stable reference source and a phase detector of a wide reception range for comparing the phase of the output signal from said reference source and an output signal of said oscillator array and for generating a first control signal for said oscillator array; a second control circuit for generating a second control signal for said oscillator array for phase synchronization of said first heterodyne signal with the useful signal; a switching means for applying said first control signal to the control input of said oscillator array during a presynchronization phase, and for applying said second control signal to the control signal input of said oscillator array during a subsequent demodulation phase; and control means for switching off those circuit components required exclusively for said presynchronization phase during said demodulation phase, for monitoring at least one of said first control signal, said second control signal and the useful signal, and for switching said switching means from a position corresponding to said demodulation phase back to a position corresponding to said presynchronization phase when the assessment of the monitored signals indicates that reception is not correct.
-
Specification