Experimental optical CDMA system based on spectral amplitude encoding of noncoherent broadband sources

The aim of this work is a proof-of-concept demonstration of an optical CDMA system based on spectral amplitude encoding of incoherent broadband sources. A Light Emitting Diode is employed as a source in a multi-mode fiber-optics system, and simple pseudorandom sequences such as m-sequences are used for optical encoding. We propose a multi-pass configuration with a Littrow grating arrangement for the optical encoder and decoder. Since this is a power-limited system, the multi-pass arrangement allows us to greatly reduce the number of lossy optical components and to increase compactness and power throughput. A differential receiver with a simplified design is employed. Measurement results are presented and discussed.