The extensive experimental researches on AOTF in WDM system

With rapidly increasing demand for communication channels, wavelength division multiplexing (WDM) system are being deployed to expand the capacity. WDM systems require devices for the manipulation of multi-wavelength channels. Among these devices, the integrated acousto-optic tunable filter (AOTF) is rapidly gaining importance in the field of WDM communication systems because it has the combined features of rapid switching time, broad tuning range and parallel processing capability. The technology of hybrid unidirectional and focused transducer was adopted for the design of the AOTF. The AOTF consisted of a single-mode optical waveguide placed along the SAW propagation direction. Extensive researches areas, which were in optical add-drop multiplexers (OADM), gain equalization and optical switches, have been done.