Indoors wireless infrared communications based on spread-space holographic CDMA

We study an application of optical holographic CDMA for free-space (wireless) optical (infrared) indoor communications. First, we describe the principles of the spread-space holographic CDMA indicating the structure of the encoder and decoder and describe mathematically the receiver's processing module which is comprised of a Fourier transform lens and a holographic matched-filter. Then, we study the performance of an indoors infrared communication link using spot-diffused configuration. Free-space optical holographic CDMA processing gain (PG) can in principle be as high as 10/sup 6/-10/sup 9/ and each user can have different modulating signals (analog or digital), or different information rate with any signal shape. This high PG, can be interpreted as the high capacity of the system to support large number of users with very small bit error rate.