Two-point modulator for high frequency (HF) transceiver, e.g. in mobile radio, with phase control loop (PLL) operable at different reference frequencies, with digital signal processor provides modulation signal

摘要

Modulator PLL (1) contains phase comparator (2) with two inputs, one coupled to reference frequency (23). Its output is linked to VCO (5), whose output goes to phase comparator (2) input via adjustable frequency divider (7). To reference frequency input is coupled to digital signal processor (10) via frequency generating block (8).Processor output is coupled to output for digital modulation data, which is linked to VCO input and to control input of frequency divider. Digital filter (12) couples processor output to control input of frequency divider and has clock input (11) linked to output of frequency generating block. Independent claims are included for use of two-point modulator.