Integrated frequency selective circuit and demodulator including phase locked loop
Abstract
Abstract AN INTEGRATED FREQUENCY SELECTIVE CIRCUIT PARTICULARLY USED FOR DEMODULATING AN FM SIGNAL WHICH INCLUDES A PHASE LOCKED LOOP HAVING A PHASE COMPARATOR COUPLED TO A LOW PASS FILTER AND AMPLIFIER WITH IN TURN HAS AN OUTPUT VOLTAGE WHICH IS THE DESIRED DEMODULATED INPUT SIGNAL AND IS COUPLED TO A VOLTAGE CONTROLLED OSCILLATOR. THE FREQUENCY OUTPUT OF THE OSCILLATOR PROVIDES THE OTHER INPUT TO THE PHASE COMPARATOR TO COMPLETE THE LOOP. WITH THE USE OF THE PHASE LOCKED LOOP, TOLERANCE VARIATIONS GREATER THAN 10% IN INTEGRAL CIRCUIT ELEMENTS CAN EASILY BE TOLERATED. BACK TO BACK DIODES MAY BE INCORPORATED IN THE CIRCUITS TO PROVIDE LIMITING ACTION FOR IMPROVED INTERFERENCE REJECTION.
Inventors
- 👤 Hans R Camenzind
- 👤 Alan B Grebene
Bibliographic Details
Claims Analysis
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