Optical Transmitter for Inter-satellite Communications

For many communication applications the demand for more bandwidth is a never ending problem. Military system applications often can exceed commercial demands by an order of magnitude or more as SIGINT and IMINT data collection and transmission are keys to our National Security. Fiber optic systems using optical carriers have been demonstrated up to 160Gbps and RF modulation at over 100GHz has been demonstrated as well. In communication applications where the system must maximize dynamic range, the use of modulators with low modulator drive voltage can provide many benefits. Typical optical transmitters currently employed consist of a discrete DFB laser module followed by a discrete LiNbO3 Mach-Zehnder modulator. This configuration is often too bulky for applications where size, weight, and power trade-offs are of primary concern. What is needed for these applications are high speed optical transmitters that are compact monolithically integrated chips. Archcom’s proposal is to monolithically integrate its state of the art InP-based DFB laser technology with its InP-based multiple quantum well p-i-n 50GHz modulator technology. The monolithically integrated chip will achieve bandwidths in excess of 50GHz, modulator drive voltages less than 2V for extinction ratios of 10dB, and output optical powers of 30mW.