Method and system for controlling phase of a signal

A system for amplifying a phase shift, the system comprising:

• a transmitter for transmitting output signal, and a receiver for receiving an input signal in response to said transmitted signal;
• a reference signal generator for generating a reference signal;
• a modulation circuit, configured for varying a modulation of at least one of the signals such that a ratio between modulation amplitudes of the input signal and the reference signal is at least 0.9 and at most 1.1, and a phase difference between the reference signal and the input signal is from about 0.9π to about 1.1π;
• a signal combiner configured for summing the signals, following said variation;
• and
• a bandpass filter for filtering said output signal to form a filtered output signal, wherein a bandwidth of said bandpass filter is selected such that XG<0.1, wherein X is a noise fluctuation average of said filtered output signal, and G is an expected amplification factor of a phase shift between said input signal and said reference signal.