Subsystems, systems and interfaces for flexible bandwidth allocation in optical CDMA networks

Much progress has been made in the field of optical networks. Much of this has been based on the technology of wavelength division multiplexing. Concurrently, there has been enormous progress in the area of optical signal processing. There is significant potential in using some of the latter advances to push optics beyond its current use for simple data transport. Code division multiple access (CDMA) has been a dominant technology in the wireless domain. With rapid progress in photonic integration techniques and the resulting hope of obtaining cost-effective solutions for complex signal processing functionalities, it is worthwhile to consider the feasibility of CDMA technology in optics.; This thesis will attempt to bring together different issues in the design of optical CDMA (OCDMA) networks. It focuses on an incoherent OCDMA approach known as wavelength-hopping time-spreading which utilizes developed 2D coding techniques in wavelength and time domains. Constraints on the scalability of the 2D code matrix are derived. In addition, the capability of wavelength-hopping time-spreading to provision differentiated service by variation of the number of coded wavelengths, is explored analytically.; Subsystems needed for practical implementations include multi-wavelength laser sources, filter and timeslot tuning technologies. This thesis describes various contributions to subsystems including (a) the first demonstration of wavelength-hopping time-spreading encoding using a novel holographic Bragg grating technology which combines the merits of other filter technologies, (b) development and demonstration of various timeslot tuning technologies with rapid reconfigurability, (c) demonstration of all-optical thresholding technologies for reducing the impact of other users signals and (d) a novel receiver for enhanced performance in the presence of interference from other users.; The thesis also combines several of these subsystems to form experimental testbeds which show the feasibility of the technology. Novel experiments are also described for interfacing different types of optical networks for next-generation hybrid optical networks. Various application scenarios are presented where optical CDMA and in particular, wavelength-hopping time-spreading offers distinct advantages over other techniques.