Automatic channel switching for jamming avoidance in burst-mode packet data wireless communication networks

• US 6,327,245 B1
• Filed: 12/19/1996
• Issued: 12/04/2001
• Est. Priority Date: 06/30/1995
• Status: Expired due to Term

• Current Assignee: Philips Electronics North America Corporation (Koninklijke Philips N.V.)
• Original Assignee: Philips Electronics North America Corporation (Koninklijke Philips N.V.)
• Inventors: Satyanarayana, Shrinagesh, Melnik, George, Guida, Frank
• Primary Examiner(s): Olms, Douglas
• Assistant Examiner(s): NGUYEN, BRIAN D
• Application Number:
  US08/770,032
• Time in Patent Office: 1,811 Days
• Field of Search: 370/229, 370/230, 370/231, 370/232, 370/235, 370/236, 370/252, 370/253, 370/310, 370/328, 370/329, 370/332, 370/344, 455/78, 455/83, 455/1, 455/63, 375/202
• US Class Current: 370/229
• CPC Class Codes: H04K 3/226 Selection of non-jammed channel for communication spectrum sharing arrangements H04W16/14; selection of wireless resources by user or terminal H04W72/02
• 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 45/48 Routing tree calculation
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 36/06 Reselecting a communication resource in the serving access point
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

In a multinode, wireless packet-hopping network, all nodes operate on a same frequency, by waiting for each other. If the frequency is subject to excessive out-of-network jamming, the building computer transmits a “time-bomb”, i.e. an instruction for all nodes to change to a different frequency at a fixed time.

Claims

1. A node for use in a wireless multinode network, the node comprising:

a wireless transceiver arranged to transmit signals to and receive signals from other nodes in the network, with all nodes transmitting and receiving on a same frequency at any given time; and

a processor coupled to the transceiver which is arranged to;

detect a jammed status of the node;

provide a jammed status report to be transmitted to at least one other node or base station in the multinode network; and

process a received broadcast command, received from another node or base station in the multinode network, responsive to the jammed status report, to change the same frequency to a new same frequency for all nodes, after a fixed period of time,

wherein the jammed status may be low, medium, or high and wherein the processor causes the transceiver to transmit the jammed status report when the jammed status is medium or low but delays transmission of the jammed status report when the jammed status is high.

2. A node for use in a wireless multinode network, the node comprising:

a wireless transceiver arranged to transmit signals to and receive signals from other nodes in the network, with all nodes transmitting and receiving on a same frequency at any given time; and

a processor coupled to the transceiver which is arranged to;

detect a jammed status of the node;

provide a jammed status report to be transmitted to at least one other node or base station in the multinode network; and

process a received broadcast command, received from another node or base station in the multinode network, responsive to the jammed status report, to change the same frequency to a new same frequency for all nodes, after a fixed period of time,

wherein

the jammed status report is provided only if the duration of the jamming exceeds a threshold;

the threshold is calculated as a statistical significance of an amount of time jammed when compared with a predetermined time interval.

3. The node of claim 2 wherein the statistical significance is a percentage.

4. A network comprising a central computer and a plurality of nodes arranged to operate on a packet hopping basis, each of the central computer and the nodes being arranged to communicate wirelessly with one or more other of the central computer and the nodes, and the central computer and the nodes all being arranged to transmit and receive on a same single frequency as each other at any given time, wherein

each node comprises a respective processor arranged to

detect a jammed status of that node;

provide a jammed status report to another node or to the central computer; and

process a broadcast command, received from another node or from the centralcomputer, to change to a second frequency after a fixed period of time;

the central computer is arranged to process the jammed status report and originate the broadcast command at least once in response to the jammed status report; and

at least one of the nodes is arranged to create the jammed status report if a period of time jammed exceeds a threshold.

5. A network comprising a central computer and a plurality of nodes arranged to operate on a packet hopping basis, each of the central computer and the nodes being arranged to communicate wirelessly with one or more other of the central computer and the nodes, and the central computer and the nodes all being arranged to transmit and receive on a same single frequency as each other at any given time, wherein

each node comprises a respective processor arranged to

detect a jammed status of that node;

provide a jammed status report to another node or to the central computer; and

process a broadcast command, received from another node or from the central computer, to change to a second frequency after a fixed period of time;

the central computer is arranged to process the jammed status report and originate the broadcast command at least once in response to the jammed status report; and

at least one of the nodes is arranged to create the jammed status report after a statistical calculation indicating a significance of an amount of time jammed when compared with a predetermined time interval.

6. A network comprising a central computer and a plurality of nodes arranged to operate on a packet hopping basis, each of the central computer and the nodes being arranged to communicate wirelessly with one or more other of the central computer and the nodes, and the central computer and the nodes all being arranged to transmit and receive on a same single frequency as each other at any given time, wherein

each node comprises a respective processor arranged to

detect a jammed status of that node;

provide a jammed status report to another node or to the central computer; and

process a broadcast command, received from another node or from the central computer, to change to a second frequency after a fixed period of time;

the central computer is arranged to process the jammed status report and originate the broadcast command at least once in response to the jammed status report; and

the central computer is arranged to test, after originating the broadcast command, for acknowledge signals and to abort the broadcast command in the absence of the acknowledge signals.

7. A network comprising:

a) a central node comprising

i) a transceiver arranged to transmit and receive at a present frequency and having a transmission range;

ii) a processor arranged to perform the following operations;

A) detect a jammed status report from another node;

B) provide an order for transmission to other nodes to change the present frequency to a new frequency after a fixed period of time;

b) a plurality of additional respective nodes, each respective node comprising

i) a respective transceiver having the transmission range, each respective transceiver arranged to transmit and receive at the present frequency;

ii) a respective processor for

A) detecting a jammed status of the respective node;

B) providing the jammed status report to be transmitted to at least one other of the plurality of nodes or the central node; and

C) responding to the order, received via the transceiver, by causing retransmission of the order to at least one node and by causing the respective transceiver to transmit and receive at the new frequency;

the plurality of additional nodes comprising at least first and second sets of such nodes, the first set being within the transmission range of the central node, and the second set being outside the transmission range of the central node and reachable from the central computer by packet hopping from the first set, a duration of the fixed period of time being sufficient to exceed an expected packet hopping time from the central node to all nodes within the network.

8. The network of claim 7, wherein the jammed status is a jammed status of the respective node.

9. The network of claim 7, wherein each of the additional respective nodes further comprises means for executing some functionality other than data reception and transmission.

10. The network of claim 9, wherein the functionality is lighting control.

11. A network comprising a central computer and a plurality of nodes arranged to operate on a packet hopping basis, each of the central computer and the nodes being arranged to communicate wirelessly with one or more other of the central computer and the nodes, and the central computer and the nodes all being arranged to transmit and receive on a same single frequency as each other at any given time, wherein

each node comprises a respective processor aged to

detect a jammed status of that node;

provide a jammed status report to another node or to the central computer; and

process a broadcast command received from another node or from the central computer, to change to a second frequency after a fixed period of time;

the central computer is arranged to process the jammed status report and originate the broadcast command at least once in response to the jammed status report; and

the central computer is further arranged to perform the following operations;

originating the broadcast command at least one second time;

checking for responses from all nodes in the network; and

if all nodes have not responded, aborting the broadcast command.

12. The network of claim 11, wherein the central computer is further arranged to perform the following operation:

after aborting the broadcast command, issuing a new broadcast command.