Patent ID: 6370204
Filing Date: 2002-04-09
Classification: H03K,H04L

Abstract:
An apparatus for performing digital fractional modulation comprising:a first unit generating a fractionally modulated carrier signal having a frequency; and a second unit receiving said fractionally modulated carrier signal and multiplying the frequency of said fractionally modulated carrier signal upward to generate a high frequency signal for satellite transmission, wherein the second unit comprises: a phase locked loop circuit comprising an oscillator and a phase detector, the phase locked loop circuit receiving said fractionally modulated carrier signal and multiplying said fractionally modulated carrier signal by a first predetermined factor to produce a higher frequency signal whereby the phase of said higher frequency signal tracks the phase of the fractionally modulated carrier signal; a multiplier multiplying the higher frequency signal by a second predetermined factor to produce a minimum shift key (MSK) modulated signal; a power amplifier amplifier the MSK modulated signal; and a transducer having a transmitter component, said transmitter component receiving the amplified signal and sending said amplified signal to a feed horn for ultimate transmission to the satellite.