Pulse frequency division multiplexing is a new way to increase the capacity of a local fiber-optic communications network

A method of pulse frequency division multiplexing (PFDM) to increase the capacity of a local fiber-optic communications system (hundreds of simultaneous users with a throughput of tens or potentially even hundreds of gigabits per second) is proposed. Pulse frequency (repetition rate of laser pulses or modulation rate) can, in theory, be used to identify signals from individual customers. The main advantage of the proposed technique is that the particular pulse frequency could be better controlled electrically than the particular optical frequency of semiconductor lasers. It is asynchronous, which is another advantage over time division multiplexing systems. Further development of the key components, such as optical AND gates, optical threshold devices, adjustable optical delay lines, stabilized and very short pulse laser sources, and pulse compression elements, is important for the practical realization of the proposed method