A reconfigurable wavetable-based event-driven multiphase RF modulator

A reconfigurable multiphase (MP) modulator is presented that avoids continuous generation and distribution of MP clocks by reconstructing switching waveforms from a memory-stored wavetable using an event-driven pulse generator. Reconfiguration is achieved by updating the wavetable, enabling changes in phase count (e.g., 8–16 phases) and duty cycle to tune spectral performance without modifying the pulse-generator core. A waveform-level proof-of-concept transmitter chain with a commercially available RF amplifier is demonstrated at carrier frequencies of 0.9, 2.4, 3.7, and 6 GHz. Orthogonal frequency-division multiplexing signals with bandwidths up to 500 MHz 500\,MHz 500 M H z are used. In 8-phase, 50 percent sign 50% 50 % duty cycle operation, the measured out-of-band and in-band linearity achieves minus 48.3 dBc -48.3\,dBc − 48.3 d B c adjacent-channel leakage ratio (ACLR) with 1.56 percent sign 1.56% 1.56 % error vector magnitude (EVM). Scaling from 8 to 16 phases via wavetable updates increases delivered output power by up to 1.61 dB 1.61\,dB 1.61 d B while maintaining comparable ACLR and EVM. In 6-phase, 33 percent sign 33% 33 % duty cycle operation, the measured second- and third-harmonic rejection is approximately 42 dBc 42\,dBc <m