SNR of 3-stage fiber delay lines based on SOAs in microwave photonics link

Signal to noise ratio (SNR) of multi-stage optical fiber delay lines based on semiconductor optical amplifiers (SOAs) is demonstrated with experiments by carrying 8 GHz microwave sinusoidal signal. We conclude that, higher input power of microwave source and the higher gain of SOAs will improve the performance of SNR. What's more, it is shown that more stages of optical fiber delay lines based on SOAs decrease the SNR.