Digital Radio over Fibre for Future Broadband Wireless Access Network Solution

Digital systems are more flexible and environment-process-tolerant than analogue systems. They are more reliable and robust against cross-talk, interference and channel noises, and are capable of covering higher dynamic range than analogue systems. Wideband electronic analogue to digital conversion (ADC) systems have critical problems encountered in high-frequency broadband communication systems that the recent electronic ADCs (EADC) have experienced those such as uncertainty of sampling time. In this paper, an 80Gigasample/s all photonic sampling and quantization ADC and photonic digital to analogue conversion system with six effective number of bits (ENOB) is designed. By using this Photonic ADC (PADC), a digital radio over fibre link for wireless radio frequency (RF) signal transportation over 50 km single mode fibre has been designed whose performance is investigated in this paper.