Photonic wavelength-division and time-division hybrid switching networks for large line-capacity broadband switching systems

It is shown that the multiplexity of hybrid switching networks, which is given by the product of wavelength-division multiplexity and time-division multiplexity, is sufficient to allow fabrication of large-line-capacity broadband switching systems. It is suggested that the achievement of eight wavelength-division multiplexity and eight time-division multiplexity for 150-Mb/s signals is a reasonable short-range, objective considering current semiconductor optical device technology. It is shown that a proposed 4096-line four-state junctor network for a 150-Mb/s channel has inherent advantages, providing more compact hardware and fewer optical fiber connections than conventional electronic/photonic broadband switching networks