Time and wavelength division switching system

A time and wavelength division multiplexed optical switching system comprising:

• a plurality of inlet highways to each of which a plurality of incoming TDM signals of different optical wavelengths are applied;
• a plurality of first time and wavelength (T.times.W) switches respectively associated with said inlet highways, each of said T.times.W switches comprising a plurality of wavelength selector means for selecting one of the incoming TDM channels which is supplied on a first wavelength from the associated inlet highway in response to a first control signal applied thereto, and a plurality of time-slot switching and wavelength conversion stages associated respectively with said wavelength selector means, each of said stages being capable of deriving from a first time slot of a TDM channel selected by the associated T.times.W switch an output signal of a second time slot carried on a second wavelength in response to a second control signal applied thereto;
• a plurality of branching couplers having inputs connected respectively to the outputs of said first T.times.W switches, said input of each of said branching couplers being branched out to a plurality of outputs thereof;
• a plurality of sets of optical devices having inputs connected respectively to the outputs of said branching couplers for selecting one of said second time slot and said second wavelength;
• a plurality of combining couplers having inputs connected respectively to the outputs of said optical devices, said input of each of said combining couplers being combined to an output of each of the combining couplers;
• a plurality of second time and wavelength (T.times.W) switches connected respectively to the outputs of said combining couplers, each of said second T.times.W switches comprising a plurality of wavelength selector means each being capable of selecting said second wavelength in response to a third control signal applied thereto, and a plurality of time-slot switching and wavelength conversion stages connected respectively to the outputs of said wavelength selector means, each of said stages being capable of selecting said second wavelength in response to a third control signal applied thereto, and a plurality of time-slot switching and wavelength conversion stages connected respectively to the outputs of said wavelength selector means, each of said stages being capable of deriving from said second time slot of the selected second wavelength an output signal of a third time slot carried on a third wavelength in response to a fourth control signal applied thereto;
• and
• a plurality of outlet highways connected respectively to the outputs of said second T.times.W switches.

A time and wavelength division multiplexed optical switching system comprising:

• a source for generating a plurality of time division multiplexed (TDM) channels of different wavelengths;
• coupling means connected to said source for coupling said TDM channels to each of a plurality of outputs thereof;
• a plurality of wavelength selector means connected respectively to the outputs of said coupling means for selecting one of said TDM channels in response to a wavelength selection command signal applied thereto;
• a plurality of optical gate means connected respectively to the outputs of said wavelength selector means for selecting a time slot of said selected TDM channel in response to a time slot selection signal applied thereto;
• and
• a plurality of subscriber terminals respectively associated with said optical gates, each of said terminals having an optoelectrical converter coupled through an optical transmission medium to the output of the associated optical gate.