Abstract

Wavelength-division multiplexing (WDM) technologies make it possible to transmit large quantities of information and provide greater flexibility and freedom in a system design.¹ In such systems, multi/ demultiplexers (MUX/DEMUXs) are key devices. Several types of MUX/DEMUXs, such as Mach-Zehnder interferometer (MZ) etc. have been developed. However, since their spectral response is intrinsically sinusoidal, pass and stop band widths are relatively narrow. Therefore, the wider pass and stop band widths are required for practical uses. A cascaded-three-MZs is proposed as one of the candidates to solve this problem.² This scheme is useful for expanding only one spectral band width, but not both spectral band widths. We present a newly designed cascaded-three-MZs to expand both wavelength band widths for the first time.

© 1995 IEEE