High bandwidth communication network and method

• US 5,612,948 A
• Filed: 11/18/1994
• Issued: 03/18/1997
• Est. Priority Date: 11/18/1994
• Status: Expired due to Term

• Current Assignee: General Dynamics C4 Systems Incorporated (General Dynamics Corporation)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Leahy, Peter J., Fette, Bruce A., Harrison, David M.
• Primary Examiner(s): MARCELO, MELVIN C
• Application Number:
  US08/342,317
• Time in Patent Office: 851 Days
• Field of Search: 370/13.1, 370/14, 370/17, 370/18, 370/50, 370/75, 370/76, 370/79, 370/84, 370/95.1, 370/95.3, 370/16, 375/202, 375/267, 375/347, 455/8, 455/9, 455/11.1, 455/33.1, 455/33.4
• US Class Current: 370/252
• CPC Class Codes: H04B 7/155 Ground-based stations H04B7/204 takes precedence
• CPC Class Codes: H04B 7/2646 for broadband transmission
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0017 where the mode-switching is based on Quality of Service requirement
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 2001/0097 Relays
• CPC Class Codes: H04W 16/26 Cell enhancers or enhancement, e.g. for tunnels, building shadow
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user

Abstract

A cellular communication network (10) and method operates at frequencies above 2 GHz and achieves widespread coverage within a cell (14) by adapting routing channels, symbol rates, and FEC coding processes (78) to current RF broadcast conditions. A portion of subscriber nodes (16) act as repeaters for a base node (12). If subscriber nodes (16) cannot directly communicate with the base node (12), their communications may be indirectly routed to the base node (12) through one or more repeating subscriber nodes (16'"'"'). If current conditions do not support a high data rate, then lower data rates are supported by selection of FEC coding processes (78). If increasingly inclusive FEC coding does not achieve a data rate supportable by current conditions, slower symbol rates may be used. Communications at slower symbol rates may utilize narrower frequency bands thus keeping wider frequency bands available for higher speed usage.

Claims

1. A method of operating a high bandwidth communication network, said method comprising the steps of:

directly receiving, at a subscriber node, signals transmitted from a base node;

identifying a communications service to be provided;

identifying a minimum data rate necessary to support said communications service;

determining whether to directly communicate between said base node and said subscriber node or to indirectly communicate between said base node and said subscriber node through a repeater subscriber node, selecting direct communication between said base node and said subscriber node when said data rate is supportable through direct communication with said base node; and

engaging in communications over said network, said communications occurring through a communication channel selected in response to said determining step.

2. A method as claimed in claim 1 wherein said determining step further comprises the steps of:

determining, in response to said signals, a symbol rate supportable by communications with said base node; and

selecting direct communication between said base node and said subscriber node when said data rate is possible with said symbol rate supportable through direct communication with said base node.

3. A method as claimed in claim 2 wherein:

said method additionally comprises the step of configuring said base node and said subscriber node to communicate at any one of two or more symbol rates; and

said engaging step engages in communications occurring at a symbol rate selected in response to said symbol rate determining step.

4. A method as claimed in claim 3 wherein:

said base node and said subscriber node are configured to engage in communications in either of a first frequency band or a second frequency band, wherein the first frequency band accommodates a higher symbol rate than the second frequency band; and

said engaging step transmits radio frequency (RF) signals and comprises the step of selecting one of said first frequency band or said second frequency band in response to said symbol rate determining step.

5. A method as claimed in claim 1 wherein:

said method additionally comprises the step of configuring said nodes to communicate using any one of two or more forward error correction (FEC) coding processes;

said method additionally comprises the step of selecting one of said FEC coding processes to use in encoding and decoding said communications; and

said engaging step comprises the step of applying said selected one of said FEC coding processes to data communicated over said network.

6. A method as claimed in claim 1 wherein said engaging step comprises the step of transmitting radio frequency (RF) signals.

7. A method as claimed in claim 6 wherein said RF signals exhibit a frequency greater than 2 GHz.

8. A method as claimed in claim 6 wherein:

said RF signals are in either of a relatively wider frequency band that accommodates a relatively higher symbol rate or a relatively narrower frequency band that accommodates a relatively lower symbol rate; and

said engaging step comprises the step of selecting one of said relatively wider and relatively narrower frequency bands in response to said determining step.

9. A method of operating a high bandwidth communication network, said method comprising the steps of:

transmitting a probe message from a base node to a repeater subscriber node;

deciding, at said repeater subscriber node in response to said probe message, whether to repeat said probe message or to refrain from repeating said probe message;

configuring said repeater subscriber node to either repeat said probe message or to refrain from repeating said probe message;

determining whether to directly communicate between said base node and a subscriber node or to indirectly communicate between said base node and said subscriber node through said repeater subscriber node; and

engaging in communications over said network, said communications occurring through a communication channel selected in response to said determining step.

10. A method as claimed in claim 9 wherein said deciding step decides to refrain from repeating said probe message when said probe message has previously been repeated a predetermined number of times.

11. A method as claimed in claim 9 additionally comprising the steps of:

evaluating signal quality at said repeater subscriber node; and

transmitting a connectivity message from said repeater subscriber node to said base node, said connectivity message identifying said repeater subscriber node to said base node and characterizing said signal quality.

12. A method of operating a high bandwidth communication network, said method comprising the steps of:

configuring a node which communicates over said network to communicate at any one of two or more symbol rates and with any one of two or more forward error correction (FEC) coding processes;

identifying a communications service to be provided;

identifying a minimum data rate necessary to support said communications service over said network;

determining, in response to said data rate identifying step whether to engage in direct communication between said node and a second node or to indirectly communicate between said node and said second node through a third node; and

engaging in communications over said network through a communication channel selected in response to said determining step, said communications occurring at a symbol rate selected in response to said data rate identifying step and with an FEC coding process selected in response to said data rate identifying step.

13. A method as claimed in claim 12 wherein said determining step comprises the steps of:

receiving, at said node, signals transmitted from said second and third nodes;

determining, in response to said signals, a symbol rate supportable by said direct communication between said node and said second node; and

selecting said direct communication between said node and said second node when said symbol rate is supportable through direct communication with said second node.

14. A method of operating a high bandwidth communication network, said method comprising the steps of:

configuring a node which communicates over said network to communicate at any one of two or more symbol rates and with any one of two or more forward error correction (FEC) coding processes;

identifying a communications service to be provided;

identifying a minimum data rate necessary to support said communications service over said network;

transmitting a probe message from a second node to a third node;

deciding, at said third node in response to said probe message, whether to repeat said probe message or to refrain from repeating said probe message;

configuring said third node to either repeat said probe message or to refrain from repeating said probe message;

determining whether to engage in direct communication between said node and said second node or to indirectly communicate between said node and said second node through said third node; and

engaging in communications over said network through a communication channel selected in response to said determining step, said communication occurring at a symbol rate selected in response to said data rate identifying step and with an FEC coding process selected in response to said data rate identifying step.

15. A wireless communication network subscriber node for use in a network having a high likelihood of successful communications within a coverage area, said node comprising:

a symbol rate controller configured to allow said node to communicate at any one of two or more symbol rates;

a forward error correction (FEC) controller configured to apply any one of two or more FEC coding processes data being communicated;

a symbol rate predictor configured to predict a symbol rate which may be supported by communications between said subscriber node and a base node; and

a data rate controller, coupled to said symbol rate predictor, symbol rate controller, and FEC controller, said data rate controller being configured to define a data rate at which to engage in communications over said network based on information received from said symbol rate predictor and said data rate controller.

16. A subscriber node as claimed in claim 15 wherein said communications are conveyed by radio frequency (RF) signals exhibiting frequencies greater than 2 GHz.

17. A subscriber node as claimed in claim 15 additionally comprising a radio coupled to said symbol rate controller and configured to engage in communications in either of a first frequency band or a second frequency band, wherein the first frequency band accommodates a higher symbol rate than the second frequency band;

and

said symbol rate controller is configured to select one of said relatively wider and relatively narrower frequency bands in response to said data rate controller.

18. A subscriber node as claimed in claim 15 additionally comprising a channel controller coupled to said data rate controller, said channel controller being configured to determine whether to engage in direct communication between said subscriber node and said base node or to indirectly communicate between said subscriber node and said base node through a repeater subscriber node.

19. A subscriber node as claimed in claim 18 wherein:

said subscriber node additionally comprises a radio coupled to said symbol rate predictor and configured to receive signals transmitted from said base and repeater subscriber nodes;

said symbol rate predictor is configured to predict symbol rates supportable by said direct communication between said subscriber node and said base node; and

said channel controller is configured to select direct communication between said subscriber node and said base node when said data rate is compatible with said symbol rate predicted for direct communication with said base node.