synthesizer of frequencies a fractional division, a small phase jitter and use of this synthesizer

摘要

The invention relates to a synthesizer a fractional division, a small phase jitter. / p & & p & such a synthesizer comprises a controlled oscillator 11 supplying a signal of frequency f; a phase comparator receiving a reference signal supplied by an oscillator and a divider 6 and receiving a signal of frequency fsrv supplied by a variable order divider to 8; a phase accumulator 7 adding a constant increment k, at the frequency of the reference signal; a device 10 for converting the analog, 1984, -, and for correcting the value supplied by the phase accumulator 7, an adder 15 receiving a current supplied by the phase comparator 9 and a current supplied by the device 10 for the conversion, 1984, - analog correction; means 14, 13, 12, 29 for to integrate and filter a current supplied by the adder 15 and to control the slaved oscillator 11. The synthesizer according to the invention comprises a device 10 for the conversion, 1984, - analog correction, comprising a plurality of delay devices, each receiving a fraction of the binary word c supplied by the output of the phase accumulator 7, and supplying a logic signal of time proportional to the value of this fraction of the binary word c and proportional to the period 1fs; a plurality of current sources, each providing a national corresponding respectively to the maximum value of one of the fractions of the binary word c; a plurality analog switches, respectively connecting the sources has an adder and since ordered respectively by the devices of the time delay. / p & & p & application, in particular, to 29.