Loading patent…
AssigneeU.S. Philips Corporation
InventorsTheodoor A. C. M. Claasen, Gerardus C. M. Gielis, Johan M. Schmidt, Harry B. Schoonheijm
Estimating the term…
An FM-receiver with transmitter characterization, having a tuning unit, an IF-amplifier, a demodulation circuit for demodulating a discrete transmitter characterization signal, a clock regeneration circuit, a decoding device for decoding the discrete transmitter characterization signal and a signal processing unit. The clock regeneration circuit regenerates a clock signal the period of which is obtained by dividing the frequency of the stereo pilot signal. Synchronization of the clock signal phase with the phase of the clock signal used in the transmitter is carried out by detecting, using of a periodic window signal, the average phase of the code edges in the discrete transmitter characterization signal and by choosing the phase of the regenerated clock signal to be equal thereto.
A clock regeneration circuit for an FM-receiver with transmitter characterization having a tuning unit connected to an aerial input and to which there are connected one after the other, an IF-amplifier, an FM-detector, a demodulation circuit for demodulating a discrete transmitter characterization signal, a decoding device for decoding the discrete transmitter characterization signal and a signal processing unit, also comprising a pilot regeneration circuit connected to the FM-detector for regenerating a stereo pilot signal, characterized in that the clock regeneration circuit comprises a phase search circuit having a cyclic counting device coupled to the pilot regeneration circuit for dividing at least a portion of the transmitter characterization signal into discrete phase steps determined by the periods of the pilot signal and also having a coincidence circuit connected to the cyclic counting device and to the demodulator for allotting phase steps to at least a portion of the pulse edges in the transmitter characterization signal, a storage circuit for storing the information about the phase steps and a phase selection circuit connected to the storage circuit for selecting the phase step in which, statistically, the greatest number of pulse edges occur in the transmitter characterization signal, the clock regeneration circuit also comprising a divider which has a setting input coupled to the phase selection circuit, a signal input to the pilot regeneration circuit and a signal output to an output of the clock regeneration circuit.
Dependencies are inferred from the claim text.