Arbitrary Microwave Waveform Generation Based on Optical Domain Modulation

Arbitrary microwave waveforms have become increasingly crucial for diverse applications, including high-capacity wireless communication, advanced radar systems, electronic countermeasures, and precision instrumentation. Generating arbitrary microwave waveforms with precise and flexible control over amplitude, phase, and frequency is critical to meet these applications’ stringent performance demands. In contrast to conventional electronic waveform generators, photonic generation methods overcome inherent limitations, offering substantial benefits like ultrabroad bandwidth, high-frequency operation, resistance to electromagnetic interference, and superior reconfigurability. This article reviews recent developments in photonic generation of arbitrary microwave waveforms, focusing on several prominent optical-domain techniques, including frequency-to-time mapping (FTTM), direct space-to-time mapping (DST), temporal pulse shaping (TPS), optical heterodyne technology, optical frequency combs (OFCs), optical injection, electro-optic modulation, and optoelectronic oscillation (OEO). We systematically analyzed the key characteristics, advantages, and application potential of these techniques, emphasizing recent research achievements and innovations. Moreover, photonic integration technology represents a pivotal step toward the practical arbitrary microwave waveforms generation. Integrated photonic microwave chips significantly reduce system size, weight, and power consumption, while enhancing stability and scalability. Such integrated systems are particularly promising for compact and portable arbitrary microwave waveforms generation in applications like on-chip radar, miniaturized communication modules, and flexible radio frequency (RF) testing platforms.