The high-power high-bandwidth photodetector is required at the base station in the Radio over Fiber（ROF）system.This paper presents a power combining circuit research on PI type photoelectric detector array.The probe is embedded in an inductor connected with artificial transmission lines.In order to obtain high power and large bandwidth signal

each group of unit structure of PI type circuit of photoelectric detector are connected with inductors based on the structure of array structure together to constitute the required structure.In order to achieve the best match

the first and final stage synthetic circuit branches are cascaded with two photodiode to reduce the equivalent capacity of synthetic circuit.Simulation results show that this arrangement can effectively combine multiple RF photocurrents while keeping the large bandwidth.Comparing with traveling wave detector array at the same level

the combining performance of PI type photoelectric detector array is better.