Configuring and Optimizing a Wireless Mesh Network

• US 20090059814A1
• Filed: 08/29/2008
• Published: 03/05/2009
• Est. Priority Date: 08/31/2007
• Status: Active Grant

• Current Assignee: Fisher-Rosemount Systems Incorporated (Emerson Electric Company)
• Original Assignee: Fisher-Rosemount Systems Incorporated (Emerson Electric Company)
• Inventors: Lucas, John M., Nixon, Mark J.
• Granted Patent: US 9,730,078 B2
• Time in Patent Office: Days
• US Class Current: 370/254
• CPC Class Codes: H04L 41/12 Discovery or management of network topologies
• CPC Class Codes: H04L 41/22 comprising specially adapted graphical user interfaces [GUI]
• CPC Class Codes: H04L 45/122 by minimising distances, e.g. by selecting a route with minimum of number of hops
• CPC Class Codes: H04W 16/18 Network planning tools
• CPC Class Codes: H04W 40/10 based on available power or energy
• CPC Class Codes: H04W 40/16 based on interference
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: Y02D 30/70 in wireless communication networks
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

An interactive software-based network design tool that may be used to simulate and view the operation of a wireless mesh device network used in a process plant, such as a wireless HART device network, allows a user to create a model of a wireless network, input several design requirements, and automatically generate and view communication routes and schedules for the wireless network. The network design tool provides an interactive graphic interface for the addition, removal, and positioning of nodes and devices within the wireless network and a menu including several interactive screens for specifying threshold values, network topology selections, routing preferences, and other configuration parameters related to generating and optimizing communication routes and schedules within the wireless mesh network. The network design tool automatically applies a set of optimization rules along with the parameters input by user to the network model in order to generate efficient network configuration data.

Claims

1. A communication modeling system stored as a set of instructions on a computer-readable medium and adapted for implementation by a computer for use in configuring a wireless communication network for a process control environment, the system comprising:

an interface module to receive input data describing a plurality of communication devices associated with the process control environment and to store the input data on a computer-readable medium;

an engine module communicatively coupled to the interface module to determine network configuration data using the input data and a set of rules associated with a wireless communication scheme to be used by the wireless communication network; and

an output module that provides the network configuration data as an output.

2. The system of claim 1, wherein the interface module receives the input data that includes geographic information related to at least some of the plurality of devices, wherein the geographic information corresponding to one of the plurality of devices is indicative of a physical location of the one of the plurality of devices relative to at least another one of the plurality of devices.

3. The system of claim 1, wherein the interface module receives the input data that includes a device type for at least one of the plurality of devices;

wherein the device type is one of;

a field device that performs a measurement or control function in the process control environment;

a router device that routes data between at least two of the plurality of devices without consuming or originating process control data;

a gateway device that connects the communication network to an external host;

or

a wireless access point that communicates with at least another of the plurality of devices in a wireless manner and with a gateway device in a wired manner.

4. The system of claim 1, wherein the interface module receives the input data that includes at least one of:

a burst rate of at least one of the plurality of devices corresponding to a rate of reporting measurements associated with process control to another one of the plurality of devices;

a power supply type of at least one of the plurality of devices corresponding to one of a permanent power source or a non-permanent power source supplying power to the at least one of the plurality of devices;

or

a signal strength of at least one of the plurality of devices corresponding to a strength of a radio signal transmitted from the the at least one of the plurality of devices.

5. The system of claim 1, wherein the communication scheme corresponds to a wireless HART®

communication protocol.

6. The system of claim 1, wherein the network configuration data includes at least one of a routing scheme to define a set of communication routes between the plurality of devices or a communication schedule to define timing of communication of the plurality of devices.

7. The system of claim 6, wherein the interface module receives the input data that includes geographic information for each of the plurality of devices;

and wherein the engine module includes;

a graph generator to define direct wireless connections between pairs of the plurality of devices as a part of the routing scheme using the geographic information.

8. The system of claim 6, wherein each communication route in the set of communication routes includes a directed graph connecting a pair of the plurality of devices via one or several direct wireless connections;

wherein the engine module includes;

a graph generator to generate a set of directed graphs using the input data.

9. The system of claim 8, wherein the interface module includes:

a parameter selection routine to specify at least one of;

a maximum number of intermediate devices to be associated with each one of the set of directed graphs;

a maximum number of devices to consider as candidates for establishing a direct wireless connection to any one of the plurality of devices;

or

a signal strength difference value for selecting between a first communication path connecting a pair of the plurality of devices and having a first number of intermediate devices and a second communication path connecting the pair of the plurality of devices having a second number of intermediate devices greater than the first number, wherein the signal strength difference corresponds to an amount by which signal strength associated of the second communication path must exceed signal strength associated with the first communication path to prefer the second communication path to the first communication path.

10. The system of claim 6, wherein the engine module includes:

an Extended Mark-up Language (XML) generator to generate an XML description of at least one of routing scheme or the communication schedule.

11. The system of claim 6, wherein each of the plurality of devices communicates wirelessly with at least another one of the plurality of devices along a corresponding direct wireless connection;

wherein the routing scheme corresponds to a plurality of graphs each including one or several direct wireless connections; and

wherein the engine module comprises;

a schedule generator to allocate a plurality of timeslots associated with a plurality of communication channels to the plurality of direct wireless connections as a part of the communication schedule.

12. The system of claim 1, wherein the engine uses the input data to generate a network model;

wherein the network model includes a plurality of nodes each corresponding to one of the plurality of devices; and

wherein the interface module includes;

a node addition routine to add a node to the plurality of nodes;

a node removal routine to remove a node from the plurality of nodes; and

a node positioning routine to associate one of the plurality of nodes with a geographical position relative to at least another one of the plurality of nodes;

wherein each of the node addition routine, the node removal routine, and the node positioning routine is responsive to user input.

13. The system of claim 12, wherein the network configuration data includes a routing scheme to define a set of communication routes between the plurality of devices;

wherein each one in the sect of communication routes is a directed graph that includes at least direct wireless connection between a pair of the plurality of devices;

wherein the interface module further includes;

a power source type selection routine to associate a specified one of the plurality of nodes with one of a first type of a power source or a second type of a power source; and

a power factor selection routine to associate the first type of with a first value of a power factor and the second type with a second value of the power factor; and

wherein the engine module includes;

a graph generator to generate the set of directed graphs using the power factor associated with each of the plurality of devices.

14. The system of claim 12, wherein the interface module further includes:

a topology selection routine select a topology for the plurality of nodes including a mesh configuration, start configuration, or a mesh star configuration;

wherein the engine module defines direct wireless connections between pairs of the plurality of devices to generate a routing scheme of the communication network in accordance with the specified topology.

15. The system of claim 12, wherein the engine uses the input data to generate a network model;

and wherein the interface module further includes;

a threshold input routine to associate a specified one of the plurality of nodes with a threshold signal strength value; and

wherein the engine module includes;

a graph generator that defines a unidirectional wireless connections to the specified one of the plurality of devices corresponding a destination from another one of the plurality of devices corresponding to a source only if a projected strength of a signal from the source to the destination exceeds the threshold signal strength.

16. The system of claim 1, wherein the engine uses the input data to generate a network model;

and wherein the interface module communicates with an input device to receive user commands to edit the network model; and

wherein the output module interacts with a display device to render a representation of the network model thereon.

17. The system of claim 16, wherein the engine module defines a set of direct wireless connections between pairs of the plurality of devices using the input data;

and wherein the interface module includes;

a graphical user interface (GUI) routine to display the plurality of devices as a plurality of nodes interconnected by the set of direct connections.

18. The system of claim 1, wherein the interface module receives the input data that includes information indicative of a physical location of a first one of the plurality of devices and a second one of the plurality of devices;

and wherein engine module estimates a quality of a wireless signal transmitted from the first one of the plurality of devices and measured at the second one of the plurality of devices using the physical location information of the first one of the plurality of devices and the second one of the plurality of devices.

19. The system of claim 1, further comprising:

a second interface module to receive live performance data from the communication network;

wherein the engine module generates the configuration data further using the live performance data.

20. The system of claim 19, wherein the second interface module receives the live performance data that includes a measurement related to at least one of:

a signal strength at one of the plurality of devices;

or

a delay associated with propagating a message from a first one of the plurality of devices to a second one of the plurality of devices.

21. A method of designing a wireless communication network for a process control environment, the method comprising:

obtaining input data descriptive of a plurality of wireless devices associated with the process control environment;

automatically applying a set of rules associated with a communication scheme to the input data to generate network configuration data used to configure the plurality of wireless devices to wirelessly communicate in the process control environment; and

providing the network configuration data as output.

22. The method of claim 21, wherein obtaining the input data for each of the plurality of wireless devices includes:

receiving a device type indication corresponding to one of a predefined types of the device; and

receiving a location indication corresponding to a physical location of the device relative to the plurality of devices.

23. The method of claim 22, wherein receiving the device type indication includes receiving the device type indication corresponding to one of a field device that performs a measurement or control function in the process control environment, a router device that routes process control data originated by a first one of the plurality of devices and addressed to another one of the plurality of devices, a gateway device that connects the communication network to an external host, or a wireless access point that communicates with at least another of the plurality of devices in a wireless manner and with a gateway device in a wired manner.

24. The method of claim 22, wherein obtaining the input data for each of the plurality of wireless devices further includes:

receiving a power level indication corresponding to a power level of a wireless signal transmitted by the device.

25. The method of claim 22, wherein obtaining the input data for each of the plurality of wireless devices further includes:

receiving a power source selection indicative of type of a power source that supplies power to the device.

26. The method of claim 21, wherein obtaining the input data includes:

providing a display interface to a user, comprising;

providing a canvass area on the display;

providing an interactive menu having a plurality of user selectable functions including at least a first function to add a representation of a device to a selected location within the canvass area and a second function to remove a selected representation of a device from the canvass area.

27. The method of claim 26, wherein providing the interactive menu further includes providing a third function to add a representation of an obstacle to a selected location within the canvass area;

wherein the obstacle positioned between a first one of the plurality of devices and a second one of the plurality of devices attenuates a wireless signal transmitted between the first and second devices.

28. The method of claim 26, wherein providing the interactive menu further includes providing a third function to specify a rate at which the device originates process control data.

29. The method of claim 21, wherein applying the set of rules to the input data includes generating a set of directed graphs connecting pairs of the plurality of devices to define a routine scheme of the communication network.

30. The method of claim 29, further comprising:

displaying at least one of a graphical representation or a textual representation of the plurality of devices and of the set of directed graphs on a display interface.

31. The method of claim 29, wherein automatically applying the set of rules to the input data further includes allocating a plurality of timeslots associated with a set of wireless channels to the plurality of devices to define a communication schedule of the communication network.

32. The method of claim 29, wherein the plurality of devices includes a gateway device to communicate with a host external to the communication network;

and wherein generating the set of directed graphs connecting pairs of the plurality of devices includes;

generating a first set of upstream directed graphs connecting each of the plurality of devices with the gateway device; and

generating a second set of downstream directed graphs connecting the gateway device to each of the plurality of devices.

33. The method of claim 29, wherein obtaining the input data for at least some of the plurality of devices includes:

obtaining a power level indication corresponding to a power level of a wireless signal transmitted by the device; and

wherein

generating a set of directed graphs connecting pairs of the plurality of devices includes;

defining a plurality of direct wireless connections between pairs of the plurality of devices, comprising;

evaluating a plurality of potential direct wireless connections at each of the plurality of devices by calculating a strength of a signal received at the device from another one of the plurality of devices using the corresponding power level indication; and

selecting direct wireless connections from the plurality of potential direct wireless based on at least the calculated strength of the signal; and

associating a subset of the plurality of direct wireless connections with each directed graph in the set of directed graphs.

34. The method of claim 21, further comprising:

receiving feedback data from the wireless communication network; and

updating the generated network configuration data based on the received feedback data.

35. The method of claim 34, wherein receiving the feedback data includes receiving a set of measurements of data propagation delay in the communication network.

36. The method of claim 34, wherein receiving the feedback data includes receiving a set of signal strength measurements at at least some of the plurality of devices.

37. The method of claim 21, further comprising:

providing a display interface to a user;

receiving a design constraint from the display interface; and

wherein

applying the set of rules to the input data includes generating a routing scheme and a communication schedule for the communication network in view of the design constraint.

38. The method of claim 37, wherein the design constraint includes one of a maximum number of intermediate devices associated with a directed graph connecting a pair of the plurality of devices;

a maximum number of devices having a direct wireless connection to any one of the plurality of devices;

or a minimum number of devices to consider at one of the plurality of devices when defining a directed graph from the one of the plurality of devices to another one of the plurality of devices.

39. A communication modeling system stored as a set of instructions on a computer-readable medium and adapted for implementation by a computer for designing a wireless communication network for a process control environment, the system comprising:

a user interface module to receive input data descriptive a plurality of wireless devices associated with the process control environment and to store the input data on a computer-readable medium; and

an engine module communicatively coupled to the interface module to automatically generate network configuration data using the input data for the plurality of wireless devices;

wherein the network configuration data includes a routing scheme defined as a set of communication paths connecting pairs of the plurality of devices and a communication schedule to define timing of communication of the plurality of devices;

the engine module including;

a graph generator to define a plurality of direct wireless connections between pairs of the plurality of devices and to generate the set of directed graphs using the plurality of direct wireless connections; and

a schedule generator to associate the plurality of timeslots with the plurality of communication channels, and to allocate the plurality of timeslots to the plurality of direct wireless connections defined by the graph generator.

40. The software tool of claim 39, wherein the communication network applies a set of rules associated a wireless HART®

communication protocol to generate the network configuration data.

41. The software tool of claim 39, wherein the input data descriptive of the plurality of devices includes:

data corresponding to at least one field device performing a measurement or control function in the process control environment; and

data corresponding to a gateway device communicatively coupled to an external host operating outside the communication network.

42. The software tool of claim 41, wherein the user interface module includes a burst rate selection routine to associate a specified one of the plurality of devices with a rate of reporting measurements associated with process control to the gateway device.

43. The software tool of claim 39, wherein the communication schedule includes:

a set of dedicated timeslots corresponding to an exclusive use by a pair of the plurality of devices on the corresponding communication channel; and

a set of shared timeslots corresponding to a shared use by two or more of the plurality of devices on the corresponding communication channel.

44. The software of claim 43, wherein a user interface module includes:

a graphical user interface (GUI) routine to graphically render the generated communication schedule, wherein the GUI renders the first set of dedicated timeslots using a first graphic and renders the second set of dedicated timeslots using a second graphic;

wherein the first graphic and the second graphic differ in at least one of a color, a shape, or a size.

45. A software tool stored as a set of instructions on a computer-readable medium and adapted for implementation by a computer for designing a communication network that includes a plurality of devices operating in a process control environment, the tool comprising:

an interface module to facilitate creation or modification of an interactive model of the communication network, wherein the interactive model is stored as data on a computer-readable medium; and

an engine module communicatively coupled to the interface module to automatically generate a parameter set for operating the communication network based on the interactive model.

46. The software tool of claim 45, wherein the parameter set is associated with at least one of a routing scheme of the communication network or a communication schedule of the plurality of devices.

47. The software tool of claim 46, wherein the engine module includes:

a graph generator to define direct wireless connections between pairs of the plurality of devices using at least a geographic information associated with each of the plurality of devices and stored as a part of the interactive model;

wherein the routing scheme includes the defined direct wireless connections.

48. The software tool of claim 46, wherein the engine module includes:

a graph generator to generate a set of directed graphs connecting pairs of the plurality of devices via one or several direct wireless connections to define the routing scheme of the communication network.

49. The software tool of claim 45, wherein the interface module includes:

a node addition routine to add a node to a plurality of nodes of the interactive model corresponding to the nodes of the wireless communication network;

a node removal routine to remove a node from the plurality of nodes; and

a node positioning routine to associate one of the plurality of nodes with a geographical position relative to at least another one of the plurality of nodes;

wherein each of the node addition routine, the node removal routine, and the node positioning routine is responsive to user input.

50. The software tool of claim 45, wherein the interface module includes:

a graphical user interface (GUI) routine to display the interactive model as a plurality of nodes interconnected by a set of direct connections corresponding to the parameter set generated by the engine module.