System and method for offsetting channel spectrum to reduce interference between two communication networks

• US 20040203393A1
• Filed: 03/13/2002
• Published: 10/14/2004
• Est. Priority Date: 03/13/2002
• Status: Abandoned Application

• Current Assignee: Hughes Electronics Corporation (Rtx Corporation)
• Original Assignee: Hughes Electronics Corporation (Rtx Corporation)
• Inventors: Chen, Xiang
• Application Number:
  US10/096,600
• Publication Number:
  US 20040203393A1
• Time in Patent Office: Days
• US Class Current: 455/63.1
• CPC Class Codes: H04B 7/18536 Shadowing compensation therefor, e.g. by using an additional terrestrial relay
• CPC Class Codes: H04B 7/18563 Arrangements for interconnecting multiple systems data switching networks H04L12/00

Abstract

A system and method for operating two components of a communication system within the same spectrum is provided. A first component is associated with a first set of channels and a second component is associated with a second set of channels. The center frequencies of the first set of channels are offset from the center frequencies of the second set of channels and rolloff filtering is employed in order to minimize interference between channels in the first component and overlapping channels in the second component.

Claims

1. A system for communicating over two networks using the same spectrum comprising:

a first network adapted to utilize a spectrum of frequencies, said spectrum divided into a first plurality of channels; and

a second network adapted to utilize said spectrum of frequencies, said spectrum divided into a second plurality of channels, wherein said first plurality of channels are offset from said second plurality of channels.

2. The system of claim 1, wherein said first network further comprises a first transmitter comprising a channel filter.

3. The system of claim 2, wherein said channel filter comprises a raised cosine rolloff filter.

4. The system of claim 1, wherein said first plurality of channels are of equal bandwidth.

5. The system of claim 4, wherein said second plurality of channels are of equal bandwidth.

6. The system of claim 5, wherein said offset is equal to one half of the channel bandwidth.

7. The system of claim 1, wherein said first network includes a satellite network.

8. The system of claim 1, wherein said second network includes a terrestrial network.

9. A method of operating two communications networks comprising the steps of:

associating a spectrum of frequencies to a first network,

dividing said spectrum into a first plurality of channels,

associating said spectrum of frequencies to a second network, and

dividing said spectrum into a second plurality of channels, said second plurality of channels being offset from said first plurality of channels.

10. The method of claim 9, further comprising the step of transmitting a signal on a first one of said first plurality of channels.

11. The method of claim 10, further comprising the step of filtering said signal prior to said transmitting step.

12. The method of claim 11, wherein said filtering step utilizes raised cosine rolloff filtering.

13. The method of claim 9, wherein said first plurality of channels are of equal bandwidth.

14. The method of claim 13, wherein said second plurality of channels are of equal bandwidth.

15. The method of claim 14, wherein said offset is equal to one half of said channel bandwidth.

16. The method of claim 9, wherein said first network includes a satellite network.

17. The method of claim 9, wherein said second network includes a terrestrial network.

18. A computer readable medium of instructions adapted to control two communication networks comprising:

a first set of instructions adapted to control a first network to divide a spectrum of frequencies into a first plurality of channels,

a second set of instructions adapted to control said first network to transmit a first signal on a first one of said first plurality of channels,

a third set of instructions adapted to control a second network to divide said spectrum of frequencies into a second plurality of channels, said second plurality of channels being offset from said first plurality of channels, and

a fourth set of instructions adapted to control said second network to transmit a second signal on a first one of said second plurality of channels.

19. The computer readable medium of instructions as in claim 18, further comprising a fifth set of instructions adapted to control said first network to filter said first signal prior to transmitting said first signal.

20. The computer readable medium of instructions as in claim 19, wherein said filter is a raised cosine rolloff filter.

21. The computer readable medium of instructions as in claim 18, wherein said first plurality of channels are of equal bandwidth.

22. The computer readable medium of instructions as in claim 21, wherein said second plurality of channels are of equal bandwidth.

23. The computer readable medium of instructions as in claim 22, wherein said offset is equal to one half of said channel bandwidth.

24. The computer readable medium of instructions as in claim 18, wherein said first network includes a satellite network.

25. The computer readable medium of instructions as in claim 18, wherein said second network includes a terrestrial network.