MONOLITHIC BALANCED P-I-N/HBT PHOTORECEIVER FOR COHERENT OPTICAL HETERODYNE COMMUNICATIONS

Two InGaAs p-i-n photodetectors connected in a balanced configuration have been monolithically integrated, for the first time, with a transimpedance preamplifer made from InP-InGaAs heterojunction bipolar transistors (HBT's) to realize a balanced OEIC receiver. The receiver, with a bandwidth of 3 GHz and a common mode rejection of 25 dB, has a sensitivity of -49 dBm at a bit error rate of 10(-9) under NRZ FSK reception at 200 Mb/s. This is the highest sensitivity reported so far for any monolithically integrated photoreceiver.