Tham khảo tài liệu 'wdm optical interfaces for future fiber radio systems phần 5', kỹ thuật - công nghệ, kĩ thuật viễn thông phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Chapter 3 WDM Optical Interface for Simplified Antenna Base Stations a b c Fig. Optical spectra of the proposed WDM optical interface while modelled by VPI simulator using three WI-DWDM channels a the input signal at port IN b the downlink signal at port DL Drop c the recovered optical carrier at Ầ-Re-Use port and d the uplink optical mm-wave signal to be added to the interface generated by reusing the recovered optical carrier. d signal at DL Drop port and the uplink signal at ADD port generated by reusing the recovered optical carrier were also quantified which are shown in Fig. . The error-free at a BER of 10-9 data recovery and the recovered optical spectra verified 105 Chapter 3 WDM Optical Interface for Simplified Antenna Base Stations a b Fig. Simulation BER curves that quantify the degradation of the signals due to traversing the proposed interface a the recovered downlink signal at DL Drop port and b the uplink signal generated by reusing the recovered optical carrier at ADD port. the functionality of the proposed interface which was later demonstrated in experiment as described in Section Effects of the Performance of O E Devices The overall receiver sensitivity of the experimentally demonstrated system incorporating the proposed interface irrespective of direction of communication is less than or equal to dBm at a BER of 10-9 which is very poor and needs to be improved through further investigation. The performance of the optoelectronic and electrooptic devices such as DE-MZMs and the PD play a very important role in limiting the overall performance of the link. The DE-MZMs used in the experiment exhibit a CSR from 22 to 28 dB. Also the PD used in the experiment had a responsitivity of less than . If the performance of O E devices can be improved either by replacing it with better performing devices or by applying some external 106 Chapter 3 WDM Optical Interface for Simplified Antenna Base Stations performance enhancing .
