Frequency code multiple access, a new physical layer for optical metropolitan area networks

The optical physical layer design of optical communication networks is most commonly based on intensity modulation and direct detection. This thesis proposes a multilevel frequency shift keyed optical system as an alternative. The features of this optical link design enable a multiple access scheme to be employed on a subwavelength granularity, the scheme is denoted Frequency Code Multiple Access (FCMA). Each channel of the multiplexed signal is separated out at the receiver using a parallel architecture of harmonically related Mach-Zehnder optical filters. The demultiplexing is effected passively in the optical domain.;Some network architectures are suggested in this work where the unique features of FCMA can be exploited. The majority of this dissertation concentrates on the construction of the enabling network components and the performance of a prototype single wavelength FCMA system.;The performance matrix suggests that FCMA is limited to applications with transmitted symbol rates ranging from 622 Mega-symbols per second to 2488 Mega-symbols per second (two common SONET line rates). Transmission is limited to distances ranging from tens of kilometers to a couple hundred kilometers which suggests a metropolitan area network application. The number of channels that can be multiplexed is limited by the linewidth of the transmission light source.