High precision method and device for the dynamic measurement of the effective linearity of a linear frequency modulation

摘要

A method and device for the high precision measurement of the instantaneous frequency of the linear frequency modulation of a signal. The linearly frequency-modulated signal is sent to a phase discriminator with delay line (1) which beats the modulated signal with an identical but delayed signal. The resultant beat signal is digitised by a digital coding circuit (4), and then vectorially demodulated by a vector demodulation circuit (5). A device (6) extracts the phase of the beat signal due to the non-linearity from the signals emerging from the vector demodulation (5). A device (7) then uses the phase of the beat signal to reconstruct the instantaneous modulation frequency. Application particularly to continuous wave radar systems with linear frequency modulation. IMAGE