Method and system for generating time-frequency representation of a continuous signal

An analog system for generating a time-frequency representation of a continuous aperiodic input signal, the system comprising:

• a pulse source operable to generate a periodic train of pulses, the periodic train of pulses having a repetition period corresponding to a repetition frequency, the repetition frequency being below a bandwidth of the input signal, each pulse of the periodic train of pulses having a pulse temporal width, and the pulse temporal width being below the repetition period;
• a temporal sampling unit operable to sample the input signal using the periodic train of pulses to generate a delayed temporally sampled signal, the delayed temporally sampled signal comprising a plurality of sampled copies of the input signal, each sampled copy being spaced in function of the repetition frequency of the periodic train of pulses;
• a frequency-dependent time delay unit operable to generate, based on the plurality of sampled copies of the input signal and the repetition period, a temporally sampled delayed signal comprising a plurality of delayed sampled copies of the input signal, a spectral representation of a given delayed sampled copy being delayed in function of the repetition frequency;
• and
• a temporal evaluation unit operable to evaluate the delayed temporally sampled signal over consecutive time slots to obtain, for each consecutive time slot, a respective output signal, the respective output signal being in the time-frequency domain.