Optical fibre CDMA for access and optical networks

A new design technique for circuits capable of encoding and decoding 40 GChip/s CDMA signals is proposed. We report the concept and circuit design of two novel structures, based on the distributed amplifier/filter topology, to operate at speeds close to the cut-off frequency of the transistors employed. The main application is for generation and detection of signals in optical CDMA systems. Theoretical analysis and potential implementation using an MMIC-HEMT foundry process are presented, with predicted results based on full MMIC simulation.