Expandable multicast optical switch
A scalable multicast M×N optical switch (MCS) includes a non-scalable MCS having a plurality of (L+1)×1 selector switches east coupled at one of its L entrance ports to egress ports of the non-scalable MCS, the remaining L−1 entrance ports being coupled to an L*N upgrade ports, where M and N are integers ≧2, and L is an integer ≧1. This allows the scalable MCS to be cascaded in a daisy-chain fashion, providing scalability from the M common ports to L*M common ports. In another embodiment, the selector switches are integrated into the MCS, providing scalability of common MCS ports.
1. An expandable M×N multicast optical switch comprising:
M common ports, N add/drop ports, and L*N upgrade ports, wherein M and N are integers ≧2, and L is an integer ≧1;
a non-expandable M×N blocking multicast optical switch comprising M ingress ports each coupled to a unique one of the M common ports, and N egress ports; and
N (L+1)×1 optical splitters/combiners each comprising L+1 entrance ports and one exit port, wherein each one of the N (L+1)×1 optical splitters/combiners has one of the entrance ports coupled to a unique one of the N egress ports, and the exit port coupled to a unique one of the N add/drop ports;
wherein each one of the remaining L entrance ports of the N (L+1)×1 optical splitters/combiners is coupled to a unique one of the L*N upgrade ports.
2. A 2M×N optical switch comprising:
the expandable M×N multicast optical switch of claim 1 , wherein L=1; and
an additional multicast M×N optical switch comprising M common ports and N add/drop ports, wherein each of the N add/drop ports of the additional multicast M×N optical switch is coupled to a unique one of the N upgrade ports.
3. A 3M×N optical switch comprising:
the expandable M×N multicast optical switch of claim 1 , wherein L=2; and
first and second additional multicast M×N optical switches each comprising M common ports and N add/drop ports, wherein each of the N add/drop ports of the first and second additional multicast M×N optical switches is coupled to a unique one of the L*N upgrade ports.
4. An optical switch comprising two expandable M×N multicast optical switches of claim 1 ,
wherein N of the L*N upgrade ports of one of the two expandable M×N multicast optical switches are coupled one-to-one to N of the L*N upgrade ports of the other of the two expandable M×N multicast optical switches, thus providing a loopback capability between the N add/drop ports of the two expandable M×N multicast optical switches.
5. An optical module comprising the expandable M×N multicast optical switch of claim 1 and N coherent receivers each coupled to a unique one of the N add/drop ports.
6. An expandable M×N multicast optical switch comprising:
M common ports, N add/drop ports, and 2N upgrade ports, wherein M and N are integers ≧2;
N (M+L)×1 selector optical switches each comprising M+L entrance ports, and an exit port coupled to a unique one of the N add/drop ports;
an optical splitter coupled to the M common ports, for coupling each of the M common ports to a unique entrance port of each one of the N (M+L)×1 selector optical switches;
wherein each of the remaining L entrance ports of each of the N (M+L)×1 selector optical switches is coupled to a unique one of the L*N upgrade ports; and
first and second additional multicast M×N optical switches each comprising M common ports and N add/drop ports, wherein each of the N add/drop ports of the first and second additional multicast M×N optical switches is coupled to a unique one of the L*N upgrade ports.
7. The expandable M×N multicast optical switch of claim 6 , wherein each selector optical switch is selected from the group consisting of a LCOS optical switch, a MEMS optical switch, and a PLC optical switch.
8. The expandable M×N multicast optical switch of claim 6 , wherein the optical splitter comprises a diffractive optical element.
9. An optical module comprising the expandable M×N multicast optical switch of claim 6 and N coherent receivers each coupled to a unique one of the N add/drop ports.
10. A reconfigurable optical add/drop multiplexor comprising:
first and second expandable M×N multicast optical switches, each comprising:
M common ports, N add/drop ports, and L*N upgrade ports, wherein M and N are integers ≧2, and L is an integer ≧1;
a non-expandable M×N multicast optical switch comprising M ingress ports each coupled to a unique one of the M common ports, and N egress ports; and
N (L+1)×1 optical couplers each comprising L+1 entrance ports and one exit port, wherein each one of the optical couplers has one of the entrance ports coupled to a unique one of the N egress ports, and the exit port coupled to a unique one of the N add/drop ports;
wherein each one of the remaining L entrance ports of the N (L+1)×1 optical couplers is coupled to a unique one of the L*N upgrade ports; and
first and second 1×(M+1) input wavelength-selective optical switches, and first and second (M+1)×1 output wavelength-selective optical switches;
wherein one of the M+1 output ports of the first input wavelength-selective optical switch is coupled to one of the M+1 input ports of the first output wavelength-selective optical switch, and one of the M+1 output ports of the second input wavelength-selective optical switch is coupled to one of the M+1 input ports of the second output wavelength-selective optical switch;
wherein a first one of the remaining M output ports of the first and second input wavelength-selective optical switches is coupled to first and second of the M common ports of the first expandable M×N multicast optical switch, respectively; and
wherein a first one of the remaining M output ports of the first and second output wavelength-selective optical switches is coupled to first and second of the M common ports of the second expandable M×N multicast optical switch, respectively.
11. The reconfigurable optical add/drop multiplexor of claim 10 , further comprising N coherent optical receivers each coupled to a unique one of the N add/drop ports of the first expandable M×N multicast optical switch.
12. The reconfigurable optical add/drop multiplexor of claim 10 , further comprising:
third and fourth expandable M×N multicast optical switches, wherein each add/drop port of the third and fourth expandable M×N multicast optical switches is coupled to a unique one of the upgrade ports of the first and second expandable M×N multicast optical switches, respectively;
third and fourth 1×(M+1) input wavelength-selective optical switches, and third and fourth (M+1)×1 output wavelength-selective optical switches;
wherein one of the M+1 output ports of the third input wavelength-selective optical switch is coupled to one of the M+1 input ports of the third output wavelength-selective optical switch, and one of the M+1 output ports of the fourth input wavelength-selective optical switch is coupled to one of the M+1 input ports of the fourth output wavelength-selective optical switch;
wherein a first one of the remaining M output ports of the third and fourth input wavelength-selective optical switches is coupled to first and second of the M common ports, respectively, of the third expandable M×N multicast optical switch; and
wherein a first one of the remaining M output ports of the third and fourth output wavelength-selective optical switches is coupled to first and second of the M common ports, respectively, of the fourth expandable M×N multicast optical switch.
13. A reconfigurable optical add/drop multiplexor comprising:
first and second expandable M×N multicast optical switches, each comprising:
M common ports, N add/drop ports, and L*N upgrade ports, wherein M and N are integers ≧2, and L is an integer ≧1;
N (M+L)×1 selector optical switches each comprising M+L entrance ports, and an exit port coupled to a unique one of the N add/drop ports; and
an optical splitter coupled to the M common ports, for coupling each of the M common ports to a unique entrance port of each one of the N (M+L)×1 selector optical switches;
wherein each of the remaining L entrance ports of each of the N (M+L)×1 selector optical switches is coupled to a unique one of the L*N upgrade ports; and
first and second 1×(M+1) input wavelength-selective optical switches, and first and second (M+1)×1 output wavelength-selective optical switches;
wherein one of the M+1 output ports of the first input wavelength-selective optical switch is coupled to one of the M+1 input ports of the first output wavelength-selective optical switch, and one of the M+1 output ports of the second input wavelength-selective optical switch is coupled to one of the M+1 input ports of the second output wavelength-selective optical switch;
wherein a first one of the remaining M output ports of the first and second input wavelength-selective optical switches is coupled to first and second of the M common ports of the first expandable M×N multicast optical switch, respectively; and
wherein a first one of the remaining M output ports of the first and second output wavelength-selective optical switches is coupled to first and second of the M common ports of the second expandable M×N multicast optical switch, respectively.
14. The reconfigurable optical add/drop multiplexor of claim 13 , further comprising N coherent optical receivers each coupled to a unique one of the N add/drop ports of the first expandable M×N multicast optical switch.
15. The reconfigurable optical add/drop multiplexor of claim 13 , further comprising:
third and fourth expandable M×N multicast optical switches, and wherein each add/drop port of the third and fourth expandable M×N multicast optical switches is coupled to a unique one of the upgrade ports of the first and second expandable M×N multicast optical switches, respectively;
third and fourth 1×(M+1) input wavelength-selective optical switches, and third and fourth (M+1)×1 output wavelength-selective optical switches;
wherein one of the M+1 output ports of the third input wavelength-selective optical switch is coupled to one of the M+1 input ports of the third output wavelength-selective optical switch, and one of the M+1 output ports of the fourth input wavelength-selective optical switch is coupled to one of the M+1 input ports of the fourth output wavelength-selective optical switch;
wherein a first one of the remaining M output ports of the third and fourth input wavelength-selective optical switches is coupled to first and second of the M common ports, respectively, of the third expandable M×N multicast optical switch; and
wherein a first one of the remaining M output ports of the third and fourth output wavelength-selective optical switches is coupled to first and second of the M common ports, respectively, of the fourth expandable M×N multicast optical switch.