Multi-beam communication system and method

• US 7,706,787 B2
• Filed: 03/21/2007
• Issued: 04/27/2010
• Est. Priority Date: 03/21/2007
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Com DEV International Limited (Honeywell International Inc.)
• Inventors: Jones, Trevor, Malarky, Alastair
• Primary Examiner(s): Gesesse, Tilahun
• Application Number:
  US11/689,249
• Publication Number:
  US 20080233865A1
• Time in Patent Office: 1,133 Days
• Field of Search: 455/429, 455/427, 455/12.1, 455/13.3, 455/447
• US Class Current: 455/429
• CPC Class Codes: H04B 7/18515 Transmission equipment in satellites or space-based relays

Abstract

A method of flexibly allocating capacity in a satellite coverage area, comprising establishing a frequency reuse pattern of at least two interleaved sets of cells, assigning a polarization to each set of cells, such that adjacent sets of cells alternate in orthogonal polarization, flexibly assigning satellite transmit power to at least one cell, flexibly assigning frequency and bandwidth to at least one cell, and moving frequencies, bandwidths, and satellite transmit power among the cells within each set, independently of the other sets, ensuring that at all times no two adjacent cells within a given set share a common frequency.

Claims

1. A method for accommodating changes in capacity requirements in the service area of at least one satellite comprising:

subdividing the service area into at least two interleaved sets of cells;

assigning one of two orthogonal polarizations to each set of cells, such that adjacent cells from different sets alternate in polarization;

providing for flexible allocation of satellite transmit power to one or more cells in at least a first set of cells;

providing for flexible allocation of bandwidth and frequency to one or more cells in, at least, the first set of cells, and providing that no two adjacent cells within the sets of cells share a common frequency at any given time; and

,

reallocating satellite transmit power, bandwidth and frequency among the cells of at least the first set of cells, independently of the satellite transmit power, bandwidth and frequencies of the cells in other sets of cells, in response to changes in capacity requirements in the service area.

2. The method of claim 1, further comprising reallocating satellite transmit power with frequency among the cells of, at least, the first set of cells such that the power flux densities of proximal cells having the same frequency and polarization are substantially uniform.

3. The method of claim 1, wherein each cell within the first set of cells is adjacent to a maximum of two other cells from the first set of cells.

4. The method of claim 1, wherein a plurality of satellite beams servicing the at least two interleaved sets of cells are projected from one of, a single satellite, and at least two different collocated satellites.

5. A method for accommodating changes in capacity requirements in a service area covered by at least two orbital slots, the method comprising:

subdividing the service area into at least two interleaved sets of cells;

providing for at least two sets of beams from a first satellite in a first orbital slot to service at least two of the interleaved sets of cells;

assigning a polarization to each set of beams from the at least one satellite in the first orbital slot, such that the sets of beams servicing the interleaved sets of cells from the first orbital slot alternate in polarization;

providing for at least one set of beams from a second satellite in a second orbital slot to service at least one of the at least two interleaved sets of cells;

assigning a polarization to each set of beams from the second satellite such that the sets of beams servicing interleaved sets of cells from the second orbital slot alternate in polarization, and such that, for a set of cells serviced by two sets of beams from the first and second orbital slots, the two sets of beams are of orthogonal polarization;

providing for flexible allocation of satellite transmit power to at least one cell;

providing for flexible allocation of bandwidth and frequency to at least one cell, and providing that no two beams from a common orbital slot servicing two adjacent cells within a set of cells share a common frequency at any given time; and

,

reallocating satellite transmit power, bandwidth and frequency among the cells of at least one set of cells serviced from the first orbital slot, independently of the satellite transmit power, bandwidth and frequencies of the cells in other sets of cells serviced from the first orbital slot, and independently of the satellite transmit power, bandwidth and frequencies of the cells in all sets of cells serviced from the second orbital slot, in response to changes in capacity requirements in the service area.

6. A method for accommodating changes in capacity requirements in a service area covered by at least two orbital slots, the method comprising:

subdividing the service area into at least two interleaved sets of cells;

providing for at least two sets of beams from a first satellite in a first orbital slot to service at least two of the interleaved sets of cells;

assigning a polarization to each set of beams from the at least one satellite in the first orbital slot, such that the sets of beams servicing the interleaved sets of cells from the first orbital slot alternate in polarization;

providing for at least one set of beams from a second satellite in a second orbital slot to service at least one of the at least two interleaved sets of cells;

assigning a polarization to each set of beams from the second satellite such that the sets of beams servicing interleaved sets of cells from the second orbital slot alternate in polarization, and such that, for a set of cells serviced by two sets of beams from the first and second orbital slots, the two sets of beams have the same polarization;

providing for flexible allocation of satellite transmit power to at least one cell;

providing for flexible allocation of bandwidth and frequency to at least one cell, and providing that no two beams from a common orbital slot servicing two adjacent cells within a set of cells share a common frequency at any given time; and

,

reallocating satellite transmit power, bandwidth and frequency among the cells of at least one set of cells serviced from the first orbital slot, independently of the satellite transmit power, bandwidth and frequencies of the cells in other sets of cells serviced from the first orbital slot, and independently of the satellite transmit power, bandwidth and frequencies of the cells in all sets of cells serviced from the second orbital slot, in response to changes in capacity requirements in the service area.

7. A method of using a flexible frequency reuse pattern to accommodate changing capacity requirements in a satellite service area wherein the method comprises:

establishing a flexible frequency reuse pattern comprising at least two interleaved sets of co-polarized cells, wherein no two adjacent cells of a single set may share a common frequency, and wherein the polarization of each set of cells is orthogonal to the polarization of the adjacent interleaved sets of cells;

providing for flexible allocation of bandwidth and frequency to at least one cell, and providing that no two beams from a common orbital slot servicing two adjacent cells within a set of cells share a common frequency at any given time; and

reallocating satellite transmit power, bandwidth and frequency among the cells of at least one set, independently of the satellite transmit power, bandwidth and frequencies of other sets, in response to changes in capacity requirements in the service area.

8. The method of claim 7, wherein the frequency reuse pattern is projected from one of, a single satellite, at least two different collocated satellites and at least two different satellites occupying at least two different orbital slots.

9. A transmitting system for transmitting to at least a part of a set of cells within a frequency reuse pattern for a multi-beam satellite communications system, comprising:

a flexible filtering stage, having an uplink input, and a plurality of outputs for transmitting signals from the flexible filtering stage, wherein the flexible filtering stage is configured to flexibly allocate frequencies and bandwidths among the outputs;

a flexible amplification stage coupled to the outputs of the flexible filtering stage for variably amplifying the signals provided at each of the plurality of outputs; and

,

a plurality of co-polarized polarizing antenna feeds coupled to the flexible amplification stage for transmitting the amplified signals as beams to a co-polarized set of cells,

wherein the transmitting system allocates and reallocates frequencies, bandwidths, and satellite transmit power levels among the cells of the set of cells in response to capacity requirements on the ground.

10. The transmitting system of claim 9, wherein the flexible filtering stage is configured such that any two adjacent outputs never have the same frequency at a given time, such that of any two adjacent spot beams transmitted by that transmitting system never have the same frequency at a given time.

11. The transmitting system of claim 10, wherein at least one of the flexible amplification stages comprises one of Traveling Wave Tube Amplifiers and Solid State Power Amplifiers.

12. The transmitting system of claim 10, wherein the flexible filtering stage is configured to alter the frequency and bandwidth of any given spot beam transmitted from a polarizing antenna feed while the satellite is in orbit.

13. The transmitting system of claim 12, wherein the flexible amplification stage is configured to alter the satellite transmit power of any given spot beam transmitted from a polarizing antenna feed while the satellite is in orbit in order to maintain constant power flux density within the beam.

14. A multi-beam communications system comprising a plurality of the transmitting systems of claim 13.

15. A multi-beam communications system of claim 14, wherein the co-polarized polarizing antenna feeds in each transmitting system are polarized in one of two orthogonal polarizations.

16. The multi-beam communications system of claim 15, wherein the multi-beam communications system is configured to transmit interleaved co-polarized sets of cells, where adjacent sets of cells alternate in orthogonal polarization, and wherein two adjacent cells within a given set of cells never share a common frequency at a given time.

17. The multi-beam communications system of claim 16, wherein each of the transmitting systems is configured to allocate and reallocate at least one of frequencies, bandwidths, and satellite transmit power levels among the cells in the set of cells transmitted by the polarizing antenna feeds of that transmitting system, in response to capacity requirements on the ground.

18. The multi-beam communications system of claim 17, wherein the system is configured such that each of the transmitting systems allocates frequencies and bandwidths among the outputs of that transmitting system independently of the other transmitting systems in the multi-beam communications system.

19. The multi-beam communications system of claim 18, wherein the transmitting systems are supported by one satellite.

20. The multi-beam communications system of claim 18, wherein the allocations and reallocations of at least one of frequencies, bandwidth and satellite transmit power occurs when the satellite is in orbit.

21. The multi-beam communications system of claim 17, wherein the transmitting systems are located on more than one collocated satellite.

22. The multi-beam communications system of claim 20, wherein the allocations and reallocations of at least one of frequencies, bandwidth and satellite transmit power occurs when the satellite is in orbit.

23. The multi-beam communications system of claim 21, wherein the addition of an additional collocated satellite increases the capacity of at least one set of cells by facilitating concentration of frequencies among the cells.

24. The multi-beam communications system of claim 21, wherein the addition of an additional collocated satellite increases the number of cells.