A Performance Enhanced 1-Bit Bandpass Sturdy-Multi-Stage Noise Shaping Delta-Sigma Modulator for Radio-Over-Fiber Transmission Systems

This is the authors' abstract. We don't add key points for this paper.

For delta-sigma modulator (DSM), multi-stage noise shaping (MASH) and sturdy MASH (SMASH) have been introduced for wireless communications. In this work, a modified SMASH delta-sigma modulator is proposed, which significantly improves the performance compared with the existing SMASH and MASH, such as the modulator's stability and suppression of quantization noise. The proposed modified SMASH is simulated and experimentally demonstrated, and its performance is compared to the existing SMASH and MASH modulator. For a 100-MHz (20 MHz) bandwidth 64 quadrature amplitude modulation (64-QAM) orthogonal frequency division multiplexing (OFDM) signal for simulation (experiments), it is found that the proposed modified SMASH leads to about 3-dB error vector magnitude (EVM) improvement compared with the existing SMASH and MASH for radio over fiber of up to 20 km.