Millimeter-wave multi-carrier generation for WDM-ROF system without ultra-high-speed modulator

We propose a novel method of multi-carriers generation for wavelength-division-multiplexed millimeter-wave-band radio-on-fiber system, and define carrier-to-carrier rate (CCR) to evaluate the scheme performance. Firstly, we experimentally generated a super-continuum source (SCS) with 20-dB width of more than 260 nm around 1550 nm by coupling a femto-second pulses lauched by the semiconductor mode-locked laser into two passages of 5-m-long high nonlinear photonic crystal fibers (PCFs) with opposite dispersion value. Secondly, we used a sampled fiber Bragg grating (SFBG) to filter spectrum, and the results showed that spectrum was sliced into 20 channels with -0.3-0.3 dB Peak fluctuation. Moreover, each two adjacent channels can be filtered out as one of radio-frequency carriers, and the amplitude differences of two sub-carriers in wavelength-division-multiplexed millimeter-wave-band radio-on-fiber system are tiny to ensure optimal CCR.