SATELLITE COMMUNICATIONS APPARATUS AND METHODS USING ASYMMETRICAL FORWARD AND RETURN LINK FREQUENCY REUSE

• US 20100041396A1
• Filed: 10/13/2009
• Published: 02/18/2010
• Est. Priority Date: 07/29/2005
• Status: Active Grant

• Current Assignee: ATC Technology Corporation (FedEx Corporation)
• Original Assignee: ATC Technology Corporation (FedEx Corporation)
• Inventors: KARABINIS, PETER D.
• Granted Patent: US 7,917,135 B2
• Time in Patent Office: Days
• US Class Current: 455/427
• CPC Class Codes: H04B 7/18539 Arrangements for managing radio, resources, i.e. for establishing or releasing a connection

Abstract

Communications are conducted between a space-based component of the wireless communications system and radioterminals using a plurality of forward link cells and a plurality of return link cells, the return link cells having a greater number of cells per frequency reuse cluster than the forward link cells. At least some of the forward and return link cells may use at least some frequencies of a terrestrial wireless communications system having an adjacent and/or overlapping coverage area. Forward links of the at least some of the forward and return link cells may have a greater link bandwidth than return links of the at least some of the forward and return link cells.

Claims

1. A method of operating a wireless communications system, the method comprising:

transmitting information using a plurality of forward link cells each one of which is associated with a service region, wherein the plurality of forward link cells comprises a plurality of forward frequency reuse clusters, each one of which comprises at least one forward link cell of the plurality of forward link cells, and each one of which uses a set of forward link frequencies such that a set of forward link frequencies that is used by a first forward frequency reuse cluster over a first forward service region is also used by a second forward frequency reuse cluster over a second forward service region that does not substantially overlap with the first forward service region; and

receiving information using a plurality of return link cells each one of which is associated with a service region, wherein the plurality of return link cells comprises a plurality of return frequency reuse clusters, each one of which comprises at least one return link cell of the plurality of return link cells, and each one of which uses a set of return link frequencies such that a set of return link frequencies that is used by a first return frequency reuse cluster over a first return service region is also used by a second return frequency reuse cluster to provide communications over a second return service region that does not substantially overlap with the first return service region;

wherein each one of the plurality of return frequency reuse clusters comprises a number of return link cells that is greater than a number of forward link cells that is included in each one of the plurality of forward frequency reuse clusters.

2. The method of claim 1, wherein the transmitting comprises transmitting information over a bandwidth that is greater than a bandwidth that is associated with the receiving.

3. The method of claim 1, wherein the transmitting and receiving comprise transmitting and receiving information using a frequency division duplex protocol.

4. The method of claim 1, wherein the transmitting and/or receiving comprise transmitting and receiving information using a time division duplex, orthogonal frequency division multiplexed and/or orthogonal frequency division multiple access protocol.

5. The method of claim 1, wherein the transmitting and receiving are associated with a first wireless communications system and wherein at least some of the plurality of forward and/or return link cells use at least some frequencies that are associated with and/or are also used by a second wireless communications system.

6. The method of claim 1, wherein the transmitting and/or receiving comprise transmitting and receiving information using a time division multiplexed (TDM) air interface protocol, a time division multiple access (TDMA) air interface protocol, a code division multiplexed (CDM) air interface protocol, a code division multiple access (CDMA) air interface protocol, an orthogonal frequency division multiplexed (OFDM) air interface protocol, and/or an orthogonal frequency division multiple access (OFDMA) air interface protocol.

7. The method of claim 1, wherein multiple cells of the plurality of return link cells overlap a single cell of the plurality of forward link cells.

8. The method of claim 7, wherein the plurality of forward link cells comprises a forward frequency reuse cluster size that comprises one cell and wherein the plurality of return link cells comprises a return frequency reuse cluster size that comprises more than one cell.

9. The method of claim 8, wherein respective return frequency reuse clusters of the plurality of return link cells are substantially spatially coextensive with respective forward link cells of the plurality of forward link cells.

10. The method of claim 1, wherein the wireless communications system comprises a space-based component and wherein the transmitting and the receiving are associated with the space-based component.

11. The method of claim 5, wherein the first wireless communications system comprises a space-based component wherein the transmitting and the receiving are associated with the space-based component and wherein the second wireless communications system comprises a terrestrial wireless communications system,

12. A wireless communications system comprising:

a transmitter that is configured to communicate with radioterminals using a plurality of forward link cells each one of which is associated with a service region of the transmitter, wherein the plurality of forward link cells comprises a plurality of forward frequency reuse clusters, each one of which comprises at least one forward link cell of the plurality of forward link cells, and each one of which uses a set of forward link frequencies such that a set of forward link frequencies that is used by a first forward frequency reuse cluster to provide communications from the transmitter to radioterminals over a first forward service region of the transmitter is also used by a second forward frequency reuse cluster to provide communications from the transmitter to radioterminals over a second forward service region of the transmitter that does not substantially overlap with the first forward service region of the transmitter; and

a receiver that is configured to communicate with radioterminals using a plurality of return link cells each one of which is associated with a service region of the receiver, wherein the plurality of return link cells comprises a plurality of return frequency reuse clusters, each one of which comprises at least one return link cell of the plurality of return link cells, and each one of which uses a set of return link frequencies such that a set of return link frequencies that is used by a first return frequency reuse cluster to provide communications from radioterminals to the receiver over a first return service region of the receiver is also used by a second return frequency reuse cluster to provide communications from radioterminals to the receiver over a second return service region of the receiver that does not substantially overlap with the first return service region of the receiver;

wherein each one of the plurality of return frequency reuse clusters comprises a number of return link cells that is greater than a number of forward link cells that is included in each one of the plurality of forward frequency reuse clusters.

13. The system of claim 12, wherein a forward link of the forward link cells comprises a bandwidth that is greater than a bandwidth of a return link of the return link cells.

14. The system of claim 12, wherein a forward link of the forward link cells and a return link of the return link cells are based upon a frequency division duplex protocol.

15. The system of claim 12, wherein a forward link of the forward link cells and/or a return link of the return link cells is/are based upon a time division duplex, orthogonal frequency division multiplexed and/or orthogonal frequency division multiple access protocol.

16. The system of claim 12, wherein the transmitter and the receiver are associated with a first wireless communications system and wherein at least some of the plurality of forward and/or return link cells use at least some frequencies that are associated with and/or are also used by a second wireless communications system.

17. The system of claim 12, wherein the transmitter and/or the receiver is/are configured to communicate with radioterminals using a time division multiplexed (TDM) air interface protocol, a time division multiple access (TDMA) air interface protocol, a code division multiplexed (CDM) air interface protocol, a code division multiple access (CDMA) air interface protocol, an orthogonal frequency division multiplexed (OFDM) air interface protocol, and/or an orthogonal frequency division multiple access (OFDMA) air interface protocol.

18. The system of claim 12, wherein the wireless communications system comprises a space-based component and wherein the space-based component comprises the transmitter and the receiver.

19. The system of claim 16, wherein the first wireless communications system comprises a space-based component wherein the transmitter and the receiver are associated with the space-based component and wherein the second wireless communications system comprises a terrestrial wireless communications system.

20. A radioterminal configured to communicate with the system of claim 12.

21. The system of claim 12, wherein multiple cells of the plurality of return link cells overlap a single cell of the plurality of forward link cells.

22. The system of claim 21, wherein the plurality of forward link cells comprises a forward frequency reuse cluster size that comprises one cell and wherein the plurality of return link cells comprises a return frequency reuse cluster size that comprises more than one cell.

23. The system of claim 22, wherein respective return frequency reuse clusters of the plurality of return link cells are substantially spatially coextensive with respective forward link cells of the plurality of forward link cells.