LOW PHASE NOISE RF SIGNAL GENERATING SYSTEM AND METHOD FOR CALIBRATING PHASE NOISE MEASUREMENT SYSTEMS USING SAME

摘要

Very low phase noise radio frequency (RF) source having multiple discrete frequency outputs used, for example, to calibrate phase noise measurement systems, and that includes a main oscillator (12), a multiplier chain (14) receiving an output signal therefrom and includes a multiplier that multiplies the signal frequency by an integer multiplication factor, and a frequency mixer (16). The multiplier chain (14) provides an output signal to an LO input of the frequency mixer (16). A first, multi-pole switch (18) is coupled to a plurality of additional oscillators (20_n) and an IF input of the frequency mixer (16) and generates an output signal derived from a signal from at least one additional oscillator (20_n), and a control unit (38) selects additional oscillators (20_n) and a frequency thereof to enable variation of a range and number of output frequencies at an RF output of the frequency mixer (16).