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We develop the photonic approaches to manipulate microwave signals for applications such as wireless access networks, radar and warfare systems. Three system architectures are presented for the photonic manipulation of phase, frequency and modulation of microwave signals, respectively. We propose and experimentally demonstrate a simple and flexible photonic approach to implement single sideband modulation (SSB) modulation based on optical spectral filtering. The high order birefringent filter is realized through the cascaded Solc and Lyot Sagnac loops. The periodical response of the filter spectrum allows both the carrier wavelength and optical carrier to sideband ration (OCSR) to be tunable. SSB modulation over a frequency range from 5 to 40 GHz and tunable OCSR ranging from -9.174 to 34.408 dB are obtained. A frequency-multiplied and phase-shifted microwave signal is simultaneously realized by using birefringence effects in the high nonlinear fiber. The microwave signal at doubled- or quadrupled-frequency with a full 2π phase shift is obtained over a frequency range from 10 GHz to 30 GHz. We also experimentally demonstrate a novel approach to implement light controlled microwave frequency multiplication and single sideband (SSB) modulation simultaneously. By properly choosing operational parameters of the orthogonal polarized pump light to stimulate the nonlinear birefringent effect in highly nonlinear fiber, the frequency octupled microwave signal with the frequency up to 144 GHz can be generated. The SSB modulation with simultaneous suppression of the −1st and the +2nd order sidebands suppressed is also observed, and the SSB modulation from 10 to 40 GHz with OCSR ranging from −8.7 to 26.7 dB is experimentally demonstrated. The proposed techniques are vital to overcome the electronic bottlenecks, which will satisfy the worldwide demand for higher data rate and broadband transmission.
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