Adaptive Self-Monitoring of Widely-Tunable Universal WDM Transmitter

A widely tunable universal wavelength-division-multiplexed (WDM) transmitter will be a key technology for advanced battlespace platforms requiring the interconnection of a large number of sensors, data processors, and data storage equipment. In such adynamic WDM network, wavelengths are allocated to carry specific signals, adapting continuously to the information traffic conditions and the status of each piece of equipment. Semiconductor laser sources, capable of rapid and accurate programmablewavelength switching or sweeping functionality independent of a fixed frequency grid, address both the communications needs of dynamic WDM networks as well as the optical sensor units themselves and their transparent integration into the network.Requirements of sub-picometer absolute wavelength accuracy and low noise over harsh ambient conditions place stringent demands on transmitter performance that can be guaranteed only with extensive self-monitoring and feedback control within the transmittermodule itself. We propose a complementary suite of self-monitoring technologies for widely tunable transmitters that targets three key areas: laser wavelength, laser noise, and transmitter noise. These self-monitoring techniques allow robust dynamicnetworks to be deployed in which digital signals, analog signals, and optically interrogated analog signals can be transmitted simultaneously to interconnect heterogeneous network elements.