Patent EA-000497-B1 (EA)
Title: Optically cross-linked communication system
IPC: H04B10/272
Filed: 1996-06-07
Abstract: 1. A two-way optical communications switch system useful for a single elevated platform, said optical communication switch system capable of switching a large number of wide bandwidth channels, comprising: an elevated platform for hosting said optical communications switch system; a receive antenna system for receiving a first set of N beams, each of said first set of N beams servicing M customers; an electrical-to-optical modulator for forming a first set of N optical channels from respective ones of said N beams; a frequency resolver for spreading each of said first set of N optical channels in one dimension for creating a first set of NxM optical channel elements; a beam splitter image concatenator for duplicating said first set of NxM optical channel elements to create a substantially identical second set of NxM optical channel elements, said first set of NxM optical channel elements adjacent to said second set of NxM optical channel elements to form a dual virtual array having Nx2M optical channel elements and M diagonals, each of said M diagonals comprising M optical channel elements; a diagonal optical combiner for combining said M optical channel elements for each of said M diagonals into N optical outputs for forming a second set of N beams; and a transmit antenna system for transmitting said second set of N beams, each servicing M customers simultaneously. 2. The system of Claim 1 wherein said frequency resolver includes a Bragg Cell. 3. The system of Claim 2 further comprising a source terminal and a destination terminal, said source terminal routing signals through said optical communication switch system for establishing communication with said destination terminal, said source terminal and said destination terminal including control electronics to route signals through said optical communication switch system. 4. The system of Claim 3 wherein said optical communications switch system useful for routing wide bandwidth signals from the source terminal to the destination terminal. 5. The system of Claim 3 wherein said signals includes a plurality of signals within each subband useful for servicing additional customers. 6. The system of Claim 2 wherein said frequency resolver further comprises: a collimating lens disposed between said Bragg Cell and said beam splitter image concatenator, said collimating lens for collimating said NxM optical channel elements. 7. The system of Claim 2 wherein said beam splitter image concatenator includes, a beam splitter for splitting each of said first set of NxM optical channel elements to form said second set of NxM optical channel elements, and a regular mirror disposed between said beam splitter and said dual virtual array, said regular mirror for reflecting said second set of NxM optical channel elements to create a first N X M virtual array adjacent to a second NxM virtual array, said first NxM virtual array and said second NxM virtual array comprising said dual virtual array. 8. The system of Claim 2 wherein said diagonal optical combiner includes a cylindrical focusing lens disposed between said dual virtual array and said transmit antenna system, said cylindrical focusing lens for combining said M optical channel elements of said M diagonals to form N optical output channels, said diagonal optical combiner further including a multiple beam former for converting said N optical output channels into said second set of N beams. 9. The system of Claim 2 wherein said elevated platform is a satellite. 10. The system of Claim 2 wherein said elevated platform is a ground-based tower. 11. The system of Claim 2 further including a source terminal, a destination terminal, and an intermediate terminal, said source terminal re-coding a signal for routing via said intermediate terminal to said destination terminal in the event a particular channel that is selected in accordance with a predetermined encoding scheme is occupied. 12. The system of Claim 11 wherein said source terminal includes detection circuitry for detecting an occupied channel and re-coding said signals with a predetermined code when said occupied channel is detected, and said intermediate terminal including detection means for detecting said predetermined code and re-routing said signals encoded with said predetermined code. 13. The system of Claim 11 wherein said intermediate terminal is an elevated platform. 14. The system of Claim 1 wherein said wide bandwidth channels are one-way distributed video services selectable by said M customers. 15. The system of Claim 1 wherein said receive antenna system and said transmit antenna system include a set of directional antennas, said antennas employing alternating polarization to enhance isolation. 16. The system of Claim 1 wherein said N beams are further isolated by employing frequency separation between adjacent of said N beams. 17. The system of Claim 1 wherein said beams are further isolated by employing at least a second elevated platform, said elevated platform and said second elevated platform covering over lapping sectors, a source terminal and a destination terminal, the terminals each employing a directional antenna that spatially isolates one of said elevated platform. 18. The system of Claim 1 further comprising: by-pass circuitry for extracting a set of selected ones of intra-beam signals from said first set of N beams, said intra-beam signals routed directly to said second set of N beams for transmission by said transmit antenna system. 19. The system of Claim 1 wherein said receive antenna system serves for receiving N beams alternating ones of said N beams alternate a transmit frequency and a receive frequency for enhancing beam isolation. 20 A two-way communications switch system useful for a single elevated platform, said communication switch system capable of switching a large number of wide bandwidth channels, comprising: a receive antenna system for receiving a first set of N beams, each of said first set of N beams servicing M customers; an elevated platform for hosting said communication switch system; a bank of frequency selective filters for forming a first set of N channels from respective ones of said N beams, each of said first set of N channels having M signals, each of said M signals separated by frequency; a set of summation devices for forming a second set of N channels, each of the channels comprising M signals, each of said M signals from a separate one of said first set of N channels; routing means for routing said M signals from each of said first set of N channels to said summation means; and a transmit antenna system for converting said N channels into said second set of N beams and transmitting said second set of N beams servicing M customers simultaneously. 21 The system of Claim 20 further comprising a source terminal and a destination terminal, said source terminal routing signals through said communication switch system for establishing communication with said destination terminal, said source terminal and said destination terminal including control electronics to route signals through said communication switch system. 22. The system of Claim 21 wherein said optical communications switch system useful for routing wide bandwidth signals from the source terminal to the destination terminal. 23 The system of Claim 21 wherein said receive antenna system and transmit antenna system comprise a set of directional antennas, each of the antennas having beams oriented to service a distinct geographical sector. 24. The system of Claim 21 wherein said signals includes a plurality of signals within each subband useful for servicing additional customers. 25. The system of Claim 21 wherein said source terminal includes detection circuitry for detecting an occupied channel and re-coding said signals with a predetermined code when said occupied channel is detected, and said intermediate terminal including detection means for detecting said predetermined code and re-routing said signals encoded with said predetermined code. 26. The system of Claim 21 wherein said elevated platform is a satellite. 27. The system of Claim 21 wherein said elevated platform is a ground-based tower. 28. The system of Claim 21 wherein said beams are further isolated by employing at least a second elevated platform, said elevated platform and said second elevated platform having over lapping sectors, a source terminal and a destination terminal, the terminals each employing a directional antenna that spatially isolates one of said elevated platform. 29. The system of Claim 20 wherein said beams are further isolated by alternating polarized energy employed in alternating ones of said beams. 30. The system of Claim 20 wherein said beams are further isolated by employing frequency separation between adjacent ones of said beams. 31. The system of Claim 20 wherein said wide bandwidth channels are one-way distributed video services selectable by said M customers. 32. The system of Claim 20 further including a source terminal, a destination terminal, and an intermediate terminal, said source terminal re-coding a signal for routing via said intermediate terminal to said destination terminal in the event a particular channel that is selected in accordance with a predetermined encoding scheme is occupied. 33. The system of Claim 32 wherein said intermediate terminal is an elevated platform. 34. The system of Claim 20 further comprising: by-pass circuitry for extracting a set of selected ones of infra-beam signals from said first set of N beams, said infra-beam signals routed directly to said second set of N beams for transmission by said transmit antenna system. 35. A two-way optical communications switch system useful for a single elevated platform, said optical communication switch system capable of switching a large number of wide bandwidth channels, comprising: an elevated platform for hosting said optical communications switch system; means for receiving a first