IMPROVEMENTS TO BODY AREA NETWORKS

• US 20120106397A1
• Filed: 02/02/2010
• Published: 05/03/2012
• Est. Priority Date: 03/04/2009
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Abedi, Saied
• Granted Patent: US 9,072,114 B2
• Time in Patent Office: Days
• US Class Current: 370/255
• CPC Class Codes: H04L 12/28 characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks] wireless communication networks H04W ; arrangements for dividing the transmission path H04W40/00
• CPC Class Codes: H04W 72/56 based on priority criteria
• CPC Class Codes: H04W 74/08 Non-scheduled access, e.g. ALOHA hybrid access H04W74/02
• CPC Class Codes: H04W 74/0875 with assigned priorities based access
• CPC Class Codes: H04W 76/10 Connection setup
• CPC Class Codes: H04W 76/50 for emergency connections
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A method of performing communications of network devices (11E, 13) in a wireless sensor system formed of respective networks served by a first coordinator (10NB) for non beacon-mode communication and a second coordinator (10B) for beacon-mode communication, the network devices associated with at least one entity to be monitored and the method comprising: initially, placing all the network devices (11E, 13) in a first network served by the first coordinator (10NB); monitoring one or more parameter of the or each entity by sensors of the associated network devices (11E); transmitting sensor data from the network devices in the first network to the first coordinator (10NB); detecting starting or ending of an emergency state with respect to a said entity by using the monitored parameters; in response to detection of starting of the emergency state with respect to a said entity, handing over the associated network devices (11E) to the second network; transmitting sensor data from the network devices in the second network to the second coordinator (10B); and in response to detection of ending of the emergency state with respect to a said entity, handing over the associated network devices to the first network. The method may be applied, for example, to monitoring of patients in a hospital using MBANs operating in accordance with IEEE 802.15.6.

Claims

1. A wireless sensor system comprising a plurality of network devices, a first coordinator arranged to perform non-beacon-mode communication with a first subset of the network devices, and a second coordinator arranged to perform beacon-mode communication with a second subset of the devices, the system having means for determining which of the network devices to include in the first or second subsets in dependence upon whether an emergency state exists with respect to the devices.

3. The wireless sensor system according to claim 1 for monitoring one or more entities using the network devices, wherein said emergency state is an emergency affecting the entity monitored by the network devices.

4. The wireless sensor system according to claim 3 wherein the network devices are each assigned to one of a plurality of groups each for monitoring a respective entity and said emergency state is an emergency affecting the entity monitored by the group, the devices of a group being included in or handed over between said first and second subsets as a unit.

5. The wireless sensor system according to claim 3 wherein the existence or non-existence of said emergency state is determined based on a critical level of one or more parameters sensed by sensors of the network devices.

6. The wireless sensor system according to claim 3 wherein the first and second coordinators are arranged to start from an initial state in which all network devices are included in the first subset, to hand over one or more network devices from the first to the second subset in response to starting of the emergency state, and to hand over one or more network devices from the second to the first subset in response to ending of the emergency state.

2. A wireless sensor system comprising a plurality of network devices, a first coordinator arranged to perform non-beacon-mode communication with a first subset of the network devices, and a second coordinator arranged to perform beacon-mode communication with a second subset of the devices, the system having means for handing over one or more devices between the first subset and the second subset in dependence upon whether an emergency state exists with respect to the devices.

7. A coordinator in a wireless sensor system having a plurality of network devices including sensors for monitoring at least one entity, said system configured with respective networks for simultaneous beacon-mode and non beacon-mode communication of said network devices, wherein said coordinator is arranged for non beacon-mode communication with at least a subset of said network devices and is responsive to a determination of the existence of an emergency state with respect to at least one of the network devices of said subset to hand over said subset to another coordinator for beacon-mode communication.

8. A coordinator in a wireless sensor system having a plurality of network devices including sensors for monitoring at least one entity, said system configured with respective networks for simultaneous beacon-mode and non beacon-mode communication of said network devices, wherein said coordinator is arranged for beacon-mode communication with at least a subset of said network devices and is responsive to a change in an emergency state of said subset to hand over said subset to another coordinator.

9. The coordinator according to claim 8 wherein said subset of network devices are associated with an entity in an emergency state and the coordinator is further responsive to a determination of said subset being outside an allowable range of the coordinator and/or a determination that a signal quality of said subset is below a predetermined threshold to hand over said subset to another coordinator which is preferably a beacon-mode coordinator.

12. The network device according to claim 9 wherein the device is responsive to a determination that said emergency state exists to select mode (ii), and to a determination that said emergency state no longer exists to select mode (i).

10. A network device for use in a wireless sensor system for monitoring at least one entity, and adapted to perform communication by selecting between:

(i) non beacon-mode communication with a first coordinator; and

(ii) beacon-mode communication with a second coordinator;

wherein said mode (i) or (ii) is selected dynamically during operation of the system in dependence on whether an emergency state exists with respect to said entity.

11. The network device according to claim 10 wherein the network device is one of a plurality of network devices assigned to monitoring the same entity and the emergency state is determined in accordance with the level of a parameter sensed by said network device or by any of the network devices assigned to the same entity.

13. The system according to claim 3, a coordinator according to claim 7, or a network device according to claim 10, wherein each entity is a living body.

14. The system, coordinator, or network device according to claim 13 applied to monitoring one or more medical parameters of the living body.

15. A method of performing communications of network devices in a wireless sensor system formed of respective networks served by a first coordinator for non beacon-mode communication and a second coordinator for beacon-mode communication, the network devices associated with at least one entity to be monitored and the method comprising steps of:

placing all the network devices in a first network served by the first coordinator;

monitoring one or more parameter of the or each entity by sensors of the associated network devices;

transmitting sensor data from the network devices in the first network to the first coordinator;

detecting starting or ending of an emergency state with respect to a said entity by using the monitored parameters;

in response to detection of starting of the emergency state with respect to a said entity, handing over the associated network devices to the second network;

transmitting sensor data from the network devices in the second network to the second coordinator; and

in response to detection of ending of the emergency state with respect to a said entity, handing over the associated network devices to the first network.