Radio frequency local area network

• US 5,295,154 A
• Filed: 05/03/1993
• Issued: 03/15/1994
• Est. Priority Date: 10/01/1991
• Status: Expired due to Term

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: Norand Corporation (Baker Hughes Company)
• Inventors: Meier, Robert C., Luse, Ronald E., Sojka, Marvin L.
• Primary Examiner(s): Cain, David C.
• Application Number:
  US08/056,827
• Time in Patent Office: 316 Days
• Field of Search: 375/1, 370/60, 370/85.6, 370/94.1, 370/95.1, 370/77, 370/93, 379/221, 379/209, 340/825
• US Class Current: 370/351
• CPC Class Codes: G06F 1/1626 with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: G06F 15/0225 User interface arrangements, e.g. keyboard, display; Interfaces to other computer systems
• CPC Class Codes: G06K 7/1098 the scanning arrangement having a modular construction
• CPC Class Codes: H01Q 1/007 specially adapted for indoor communication
• CPC Class Codes: H01Q 1/241 used in mobile communications, e.g. GSM H01Q1/247, H01Q1/248 take precedence
• CPC Class Codes: H01Q 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001
• CPC Class Codes: H04L 12/12 Arrangements for remote connection or disconnection of substations or of equipment thereof
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/44 Distributed routing
• CPC Class Codes: H04L 45/48 Routing tree calculation
• CPC Class Codes: H04L 45/488 using root node determination
• CPC Class Codes: H04L 69/14 Multichannel or multilink protocols
• CPC Class Codes: H04L 69/32 Architecture of open systems interconnection [OSI] 7-layer type protocol stacks, e.g. the interfaces between the data link level and the physical level
• CPC Class Codes: H04L 69/324 in the data link layer [OSI layer 2], e.g. HDLC
• CPC Class Codes: H04L 69/325 in the network layer [OSI layer 3], e.g. X.25 H04L69/16 takes precedence
• CPC Class Codes: H04L 69/326 in the transport layer [OSI layer 4] H04L69/16 takes precedence
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04W 40/00 Communication routing or communication path finding
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 40/08 : based on transmission power
• CPC Class Codes: H04W 40/24 : Connectivity information management, e.g. connectivity discovery or connectivity update
• CPC Class Codes: H04W 40/34 : Modification of an existing route
• CPC Class Codes: H04W 84/04 : Large scale networks; Deep hierarchical networks
• CPC Class Codes: H04W 84/12 : WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/04 : adapted for relaying to or from another terminal or user
• CPC Class Codes: H04W 88/08 : Access point devices
• CPC Class Codes: H04W 88/14 : Backbone network devices
• CPC Class Codes: H04W 88/16 : Gateway arrangements
• CPC Class Codes: H04W 92/20 : between access points
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

An apparatus and a method for routing data in a radio data communication system having one or more host computers, one or more intermediate base stations, and one or more RF terminals organizes the intermediate base stations into an optimal spanning-tree network to control the routing of data to and from the RF terminals and the host computer efficiently and dynamically. Communication between the host computer and the RF terminals is achieved by using the network of intermediate base stations to transmit the data.

Claims

1. In a multi-hop data communication system having a host computer node, a plurality of bridging nodes, and a plurality of mobile transceiver nodes, all communicative with a gateway root node, a local area network comprising:

said plurality of bridging nodes organized to control the flow of data along communication pathways between said bridging nodes and said gateway root node by periodically broadcasting messages indicating the logical distance to said gateway root node so that said bridging nodes may communicatively attach to nodes logically closest to said gateway root node.

2. The local area network of claim 1 wherein:

said local area network is capable of routing information between said host computer node, said bridging nodes, said mobile transceiver nodes, and said gateway root node using RF signals.

3. The local area network of claim 1 wherein:

said communication pathways are created and maintained by said bridging nodes using a HELLO protocol.

4. The local area network of claim 2 wherein:

said RF signals incorporate spread spectrum technology.

5. A method of routing information in a multi-hop data communication system having a host computer node, a plurality of bridging nodes, and a plurality of mobile transceiver nodes, all communicative with a gateway, comprising the following steps:

organizing said data communication system with said gateway at the root;

periodically broadcasting messages from said gateway;

attaching those of said bridging nodes which receive the messages to said gateway;

periodically broadcasting messages from said bridging nodes that indicate a logical distance to said gateway; and

attaching by said bridging nodes to other of said plurality of bridging nodes that provide the minimum logical distance to said gateway.

6. The method of claim 5 wherein:

said step of organizing said data communication system is achieved by said bridging nodes attaching to others of said bridging nodes logically closest to the gateway without overloading any one of said bridging nodes.

7. The method of claim 6 wherein:

said attached bridging nodes use a backward learning technique to learn the correct path to route data communication between said host computer node and said mobile transceiver nodes.