Abstract:
A method of transmitting electronic signals for use with a wireless network arrangement comprising assimilating and storing data relating to successful communication routes within the network arrangement and the transmission and receiving of electronic signals between the minimum number of devices in wireless network arrangement to improve efficiency of data communication and to reduce the power consumption of the network.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent document is a national phase application filed pursuant 35 U.S.C. §371 of PCT International Application No. PCT/EP2012/056180, filed on Apr. 4, 2012, which claims priority to earlier filed British Application No. GB 1113136.4, filed on Jul. 29, 2011. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to a method for improving performance and reducing power consumption of a wireless network system and more specifically relates to a method for improving performance and reducing power consumption of a constantly supervised battery powered wireless mesh network system. 
     2. Background of the Related Art 
     Wireless mesh networks are known for their useful application in communicating information over a wide area, using a network of multiple nodes (devices) that are capable of sending and receiving data. 
     Generally, information is transmitted from a start point to an end point, both of which may be either a control panel or a device within the mesh network. In known mesh network arrangements, information may be passed via a number of devices between said start and end points, thus requiring that all devices within the mesh remain in an active state so that they are ready to send and receive messages upon demand. 
     It will be appreciated that the requirement to remain in a constantly active state is not only inefficient, but also consumes significant power. In particular, the power demands often mean that a battery powered mesh network arrangement is unfeasible, as the limitations of the battery life of each device would prevent such as mesh network from being constantly supervised (i.e. each component being in an active state). 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to improve the performance of a wireless mesh network arrangement so as to reduce power consumption of said network. 
     It is a further object of the present invention to reduce power consumption of a mesh network arrangement to the extent that a battery powered constantly supervised mesh network arrangement is viable. 
     Thus and in accordance with a first aspect of the present invention there is provided a method of transmitting electronic signals for use with a wireless network arrangement comprising assimilating and storing data indicating successful communication routes between devices and the transmission and receiving of electronic signals between the minimum number of devices in a wireless network arrangement, in accordance with the most efficient route as determined by previously successful communications. 
     Thus and in accordance with a second aspect of the present invention, there is provided a device operating in accordance with the features of the first aspect of the present invention, capable of; assimilating and storing data indicating successful communication routes between devices and the transmission and receiving of electronic signals between the minimum number of devices in a wireless network arrangement, in accordance with the most efficient route as determined by previously successful communications. 
     Preferably, the method for improving performance and reducing power consumption of a wireless mesh network arrangement, hereinafter referred to as “the method”, is capable of being incorporated into an existing mesh network hardware arrangement, without the need for replacing hardware. 
     The method may also be capable of being incorporated into inter-operable system architecture including wireless and hardwired systems. 
     Most preferably, said method may provide an improved communication route between devices which may ultimately result in devices communicating via the minimum number of wireless connections necessary. For example, it may be possible for a communication route to be established using non-adjacent devices to avoid the need for every potential device along the route to participate in data communication, thus enabling devices to be “missed out” to establish a communication route using the minimum number of network devices necessary. 
     It will be appreciated that this improves the performance and reduces the power consumption of the wireless network arrangement by increasing the efficiency of data transfer. 
     Said improved communication route may be established using information including but not limited to signal strength, previously successful routes and device location data. 
     Most preferably, power consumed by mesh network systems incorporating said method, will be sufficiently low as to allow the system to be battery operated if required or desired. 
     To achieve a reduced level of power consumption, said method may include the possibility for each device to be in an active state for periodic intervals of time, rather than being in a continuously active state, thus reducing power requirements of the mesh network system. 
     To further reduce power consumption, said method may also allow devices not participating in information transmission to remain in an inactive state, thus reducing power requirements and, in battery operated systems; prolonging battery life of the devices. 
     Preferably, the method will allow for modifications to the mesh network arrangement, such as for example as a result of external factors including but not limited to environmental changes or changes in signal strength, to allow the mesh network arrangement to continually adapt to maintain optimal performance. 
     The method may apply a “zone” structure to the mesh network arrangement to divide said mesh network into respective areas to assist in the transmission of information across said mesh network using the minimum number of intermediate devices. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will now be described further by way of example only and with reference to the accompanying drawings in which; 
         FIG. 1  shows a flow chart illustrating the method steps and; 
         FIG. 2  shows the “funnelling” principle illustrating the route of transmission of information from the devices to the Expander (control panel). 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to  FIG. 1  there is shown a flow chart illustrating the steps involved in the method of improving the performance and reducing the power consumption of a wireless mesh network. 
     A mesh network device is initially powered up by inserting a battery into said device. The device is then incorporated into a mesh network arrangement. In accordance with the first step of the method, the device is now in an active state and enters a “learning” phase during which it transmits an electronic message  2  to the Expander (mesh network control panel)  10  and waits for a reply from said Expander  10 . 
     The purpose of this learning phase is to allow the device to locate its position within the mesh network arrangement. During this learning phase, message transmission occurs over a longer time period than post-learning phase, with a typical message duration lasting over 0.5 second. 
     If the device receives a message back from the Expander  10 , said device is located within Zone  1  and accordingly recognises and stores this location information. The device is then designated as a Zone  1  device within the mesh network arrangement. 
     If the device does not receive a message back from the Expander  10 , then said device establishes that it is not a Zone  1  device. In this instance, the device then attempts to communicate with adjacent devices by sending out a further message  3 , to said adjacent devices and then awaits a reply. 
     If the device receives a reply from an adjacent device, then the device is located within Zone  2  and accordingly recognises and stores this location information. The device is then designated as a Zone  2  device within the mesh network arrangement. 
     Once a device has established itself as a Zone  2  device, this guarantees that all other Zone  2  devices or anything further away than Zone  2  will disregard the Zone  2  message and return to an inactive state, thus reducing power consumption. 
     If the device does not receive a message back from any adjacent devices, then said device establishes that it is not a Zone  2  device. In this instance, the device then attempts to communicate with further devices by sending out a message  4 , to further adjacent devices and then awaits a reply. 
     If the device receives a reply from a further adjacent device, then the device is located within Zone  3  and accordingly recognises and stores this location information. The device is then designated as a Zone  3  device within the mesh network arrangement. 
     This process can be continued to allow devices to be located further away from the Expander, thus increasing the range of the mesh network arrangement. 
     Once a new device has established itself within a particular zone, this ensures that other devices within the same zone and other devices that are located further away from the Expander  10 , automatically disregard the message being sent to the new device and return to an inactive state, thus reducing power consumption. 
     The method above effectively results in information being funneled from the devices back in towards the Expander  10 , rather than being transmitted laterally across the mesh network arrangement and also ensures that only relevant devices are participating in the information channeling. The effect of this is that only the minimum number of wireless connections is required to transmit information between the devices and the Expander  10 . This again, reduces power consumption of the devices within the mesh network. 
     Referring now to  FIG. 2  there is shown an illustration of the “funnelling” principle showing the route of transmission of information from the devices to the Expander (control panel)  10 . 
     The mesh network is arranged in a virtual “zone” configuration in which are located individual devices, capable of sending and receiving messages from adjacent devices. The zone boundaries are not specifically restricted to a finite distance but are determined by the strength of the wireless signal. 
     Devices automatically configure their location in accordance with the steps of the method outlined with reference to  FIG. 1 . The outermost device  31  in the mesh network then transmits information to the Expander  10  via intermediate devices  21 ,  11  in a funnelling-type manner, as illustrated in  FIG. 2 . This funnelling effect uses the minimum number of wireless communications necessary to transmit information between the device and the Expander  10 , as information is channelled rather than being transmitted laterally across the mesh network. 
     As well as storing information about their specific location, devices within the mesh network are also able to compile, store and transmit routing information. Said routing information details the last successful route by which information was communicated between said device and said Expander  10 . When said routing information is transmitted from the device to the Expander  10 , the Expander  10  receives this information and transmits a response via the same pathway. Similarly, when devices attempt to transmit information, they will also use the last successful route as the first pathway of choice to reach the Expander  10 . 
     This method of transmission of information reduces power consumption and increases efficiency of the mesh network arrangement by only utilising the minimum number of devices required to transmit information across the required distance. This effectively means that the mesh network is working in a similar manner to a point to point network, with the flexibility and back-up of the mesh network operational principle if the pre-established route is unsuccessful. 
     For example, if a Zone  3  device  31  attempts and fails to transmit a message to a Zone  2  device  21 , the Zone  3  device  31  can attempt to transmit a message back to the Expander  10  via an alternative pathway, such as for example via an alternative Zone  2  device  22 . Device  22  may then transmit the message to the Expander  10  via the alternative Zone  1  device  12 . This demonstrates the flexibility and “self-healing” principle of the mesh network arrangement. 
     Similarly, alternative network devices, such as  23  may be “missed out” of a communication route if there is a more efficient route that employs fewer devices to successfully communicate data between the Expander  10  and a target device. The message is therefore capable of being transmitted by non-adjacent devices, thus “jumping over” other devices within the network arrangement, to create a communication route between the Expander  10  and target device using the minimum number of devices necessary to complete the route. This is achieved as devices are capable of selectively responding to messages in accordance with previously successful communications and also in response to changes in the network arrangement such as communication failures. 
     The new routing information is stored, subject to a satisfactory signal strength being obtained using the new route. 
     By storing previously successful routing information, the method applied to the mesh network arrangement allows devices to synchronise more effectively when switching between active and de-activated states, with synchronisation improving over time. This feature of the method creates a correction factor which can be applied to the mesh network arrangement to further improve its efficiency. 
     It is of course to be understood that the invention is not intended to be restricted to the details of embodiments described above which are described by way of example only.