Patent ID: 6763055
Filing Date: 2004-07-13
Classification: H04B

Abstract:
A frequency hopping transmitter for use in a wireless data telemetry system and being adapted to generate a modulated signal having a modulation index, comprising:a memory unit adapted to store voltage controlled oscillator transfer function characterization data for a selected voltage controlled oscillator; a microprocessor unit connected to said memory unit and generating a binary transmit data signal and a first binary attenuator actuation signal, said first attenuator actuation signal being generated in response to said voltage controlled oscillator transfer function characterization data; a phase locked loop circuit including a reference oscillator, a phase detector connected to said reference oscillator, and a summing junction responsive to said phase detector and having a modulator input, said phase locked loop circuit also including a selected voltage controlled oscillator, said selected voltage controlled oscillator being responsive to said summing junction; a programmable attenuation circuit responsive to said microprocessor unit binary transmit data signal and having a first control input for generating an attenuated binary transmit data signal in response to receiving said first attenuator actuation signal on said first control input; said phase locked loop summing junction modulator input being responsive to said programmable attenuation circuit attenuated binary transmit data signal to selectively adjust the modulation index of the transmitter.