Chirped-pulse-based broadband RF channelization implemented by a mode-locked laser and dispersion.

Based on chirped pulses, a wideband radio frequency (RF) channelized receiver that can easily support hundreds of channels is proposed. The mixing chirped pulses and its own delayed copy produces an equivalent RF local oscillation (LO). The LO frequency can be changed by simply setting the delay between the two paths. Channelized receiving of broadband RF signals can be realized by parallel delay line arrays. Meanwhile, the use of in-phase/quadrature demodulation avoids the extra optical or electrical filtering as well as image interference. A receiver with channel spacing of 100 MHz, covering the spectrum from DC to 18.4 GHz is experimentally demonstrated. The performances, including signal-to-noise ratio, frequency response, spurious-free dynamic range, and image rejection, are analyzed.