Patent ID: 6097765
Filing Date: 2000-08-01
Classification: H03K,H04L

Abstract:
An apparatus for performing digital fractional modulation comprising:a first unit generating a fractionally modulated carrier signal having a frequency; anda second unit receiving said carrier signal and multiplying the frequency of said fractionally modulated carrier signal upward to generate a high frequency signal for satellite transmission, wherein the first unit comprises:a microprocessor generating tune and modulation information;a synthesizer receiving said tune and modulation information from said microprocessor and generating the fractionally modulated carrier signal;a digital to analog converter converting said fractionally modulated carrier signal to an analog carrier signal;a mixer receiving a first oscillator signal from a first oscillator and a second oscillator signal from a second oscillator and combining said first and second oscillator signals to produce a third signal with a frequency substantially equal to the frequency of said analog carrier signal;a phase detection circuit locking the phase of said first oscillator signal to the phase of said analog carrier signal; anda cable demultiplexor receiving said first oscillator signal and distributing said first oscillator signal to the second unit.