System and method for enhancing near vertical incidence skywave ("NVIS") communication using space-time coding

• US 20050220207A1
• Filed: 04/02/2004
• Published: 10/06/2005
• Est. Priority Date: 04/02/2004
• Status: Active Grant

• Current Assignee: Rearden, LLC
• Original Assignee: Rearden, LLC
• Inventors: Caimi, Frank M., Perlman, Stephen G., Cotter, Tim S., Cheponis, Mike
• Granted Patent: US 7,885,354 B2
• Time in Patent Office: Days
• US Class Current: 375/267
• CPC Class Codes: H04L 1/0618 Space-time coding

Abstract

A system and method are described in which space-time coding techniques are used to transmit and receive multiple data streams within a near vertical incidence skywave (“NVIS”) communication system. Within the NVIS communication system, multiple independent data streams may be transmitted from a transmitting station at a high radiation angle, approaching or reaching 90 degrees. The data streams are reflected off of the ionosphere of the earth and received by one or more receiving stations. In one embodiment, the space-time coding techniques are multiple-input multiple-output (“MIMO”) signal communication techniques.

Claims

1. A method comprising:

using space-time coding techniques to transmit and/or receive multiple data streams within a near vertical incidence skywave (“

NVIS”

) communication system.

2. The method as in claim 1 wherein the space-time coding techniques comprise multiple-input multiple-output (“

MIMO”

) signal communication techniques.

3. The method as in claim 1 further comprising:

retrieving data from a Web server responsive to a user request to retrieve the data; and

providing the data from the Web server to two or more of the multiple data streams.

4. The method as in claim 3 further comprising:

receiving the data from the Web server at a remote NVIS receiving station; and

distributing the data to one or more remote servers and/or clients.

5. The method as in claim 3 wherein the data from the Web server comprises a Web page with embedded links to other Web servers, the method further comprising:

retrieving data from the other Web servers responsive to detecting the embedded links; and

providing the data from the other Web servers to the two or more of the multiple data streams.

6. A system comprising:

an NVIS station having a space-time coding module to transmit and receive multiple data streams using space-time coding techniques within a near vertical incidence skywave (“

NVIS”

) communication system.

7. The system as in claim 6 wherein the space-time coding techniques comprise multiple-input multiple-output (“

MIMO”

) signal communication techniques.

8. The system as in claim 6 further comprising:

a plurality of directional antennae, each of the directional antennae to transmit one of the multiple data streams towards the ionosphere of the earth.

9. The system as in claim 8 wherein one or more of the directional antennae further receive one or more of the multiple data streams reflected from the ionosphere, the one or more of the multiple data streams having previously been transmitted from another NVIS station.

10. The system as in claim 6 further comprising:

a network link communicatively coupling the NVIS station to the Internet, the NVIS station retrieving data from a Web server over the network link responsive to a user request to retrieve the data; and

providing the data from the Web server to two or more of the multiple data streams.

11. The system as in claim 10 further comprising:

a remote NVIS station to receive the data from the Web server; and

a second communication link over which the second NVIS station distributes the data to one or more remote servers and/or clients.

12. An apparatus comprising:

a signal transmitting pipeline having a space-time encoding module to concurrently transmit a first plurality of data streams within a common frequency band via a respective plurality of directional antennae, the plurality of directional antennae to concurrently transmit the first plurality of data streams towards the ionosphere of the earth; and

a signal receiving pipeline having a space-time decoding module to concurrently receive a second plurality of data streams within the common frequency band via the respective plurality of directional antennae, the plurality of directional antennae to concurrently receive the second plurality of data streams from the ionosphere of the earth.

13. The apparatus as in claim 12 wherein the space-time encoding module comprises:

mapping logic to receive a first series of consecutive data blocks and to map each data block of the first series to a particular antennae of the plurality of directional antennae prior to transmitting.

14. The apparatus as in claim 13 wherein the space-time decoding module further comprises:

demapping logic to receive each of the second plurality of data streams from a different antennae and to reconstruct a second series of consecutive data blocks from the second plurality of data streams.

15. The apparatus as in claim 12 wherein the space-time encoding module comprises a multiple-input multiple-output (“

MIMO”

) encoding module and wherein the space-time decoding module comprises a MIMO decoding module.

16. The apparatus as in claim 14 further comprising:

a modulator to modulate first data from a first data source to generate the first series of consecutive data blocks using a specified modulation technique; and

a demodulator to demodulate the second series of consecutive data blocks to generate second data using a specified demodulation technique.

17. The apparatus as in claim 16 wherein each of the data blocks in the first series and the second series comprise complex modulation symbols generated by the specified modulation technique.

18. The apparatus as in claim 16 further comprising:

an encoder module to encode the first data from the first data source using specified data encoding techniques prior to the modulator modulating the first data; and

a decoder module to decode the second data demodulated by the demodulator using specified data decoding techniques.

19. The apparatus as in claim 18 wherein one of the specified encoding and decoding techniques comprise Viterbi encoding and decoding, respectively.

20. The apparatus as in claim 19 wherein another of the specified encoding and decoding techniques comprise Reed-Solomon encoding and decoding, respectively.