Silicon Photonics Radio-Over-Fiber Transmitter Using GeSi EAMs for Frequency Up-Conversion

In this letter, we present a silicon photonics radio-over-fiber transmitter with a microwave photonic up-conversion capability. The circuit consists of a pair of parallel GeSi intensity modulators (EAMs) in an MZI structure. We show that the up-converter/transmitter can up-convert 64-QAM data on a 1.5-GHz IF to any output carrier frequency in the 7–26 GHz range. This interval is only limited by the measurement equipment, as we demonstrate that the EAM has a 3-dB bandwidth exceeding 65 GHz. Furthermore, the linearity of the up-converter/transmitter is characterized and a spurious free dynamic range larger than $82~\text {dB}\cdot \text {Hz}^{2/3}$ is demonstrated. Using this system, we transmit up to 1.3-Gb/s 64-QAM data over 2-km SMF with a received 5.4% rms EVM.