4. Conclusion
In this paper, the multiple-optical-source-based microwave photonic filter is integrated into a
subcarrier multiplexed RoF system to perform as a demultiplexer. The peaks of the filter’s frequency
response can be used to get the desired subcarrier, and valleys of the filter can be utilized to
suppress undesirable subcarrier frequency. Since the multiple-optical-source-based microwave
photonic filter has periodic transmission peaks and non-periodic valleys, the filter’s parameters,
such as the time delay and the relative amplitude between different taps, need to be carefully
designed to demultiplex the subcarrier in this multiplexed RoF system. The system performance by
using a microwave photonic filter with two optical sources as a demultiplexer has been measured in
our experiment and verified that the microwave photonic filter integrated in the RoF system works
well as the demultiplexer. To our best knowledge, it is the first time that a microwave photonic filter
has been implemented in an RoF system as a demultiplexer and that the system performance has
been evaluated. Due to its cost-effectiveness and flexibility, this approach will have good
application potentials in the next-generation subcarrier multiplexed RoF systems.