Adaptive hybrid wireless and wired process control system

Abstract

A hybrid wired and wireless architecture for a process control system is disclosed that includes hierarchical adaptability and optimization capabilities. The system is arranged in three tiers, the first including a number of wireless end devices exchanging packets of data and/or instructions with the distributed control system, where each wireless end device is associated with one or more meters, remote terminal units, diagnostic devices, pumps, valves, sensors, or tank level measuring devices. The second tier includes a plurality of wireless routers, each including a memory that stores a routing table and a processor that routes packets. The third tier includes a master wireless gateway device operably connected to receive packets from and transmit packets to the distributed control system. The processor of each of the wireless routers routes packets across the tiers between the end devices and the wireless gateway devices based on the stored routing table.

We claim: 
     
         1 . A process control and/or automation network for a commercial or industrial processing facility, the network comprising:
 a distributed control system in a central control room within the facility;   a first tier comprising a plurality of wireless end devices receiving instructions from and/or providing data to the distributed control system, the instructions and/or data in the form of packets, each wireless end device being associated with one or more meters, remote terminal units, diagnostic devices, pumps, valves, sensors, or tank level measuring devices;   a second tier comprising a plurality of wireless routers each including a memory that stores a routing table and a processor that routes packets; and   a third tier comprising a master wireless gateway device operably connected to receive packets from and transmit packets to the distributed control system;   wherein the processor of each of the plurality of wireless routers routes packets across the three tiers between the plurality of end devices and the wireless gateway devices based on the stored routing table.   
     
     
         2 . The process control and/or automation network as in  claim 1 , further comprising a plurality of field network sets each containing one or more of the plurality of wireless routers or one or more wireless gateway devices. 
     
     
         3 . The process control and/or automation network as in  claim 2 , further comprising at least one marshalling cabinet and at least one junction box, the at least one junction box within one of the field network sets and wired to the marshalling cabinet for communication. 
     
     
         4 . The process control and/or automation network as in  claim 3 , further comprising a junction box router in wired communication between the junction box and the marshalling cabinet and in wired communication with the master gateway device. 
     
     
         5 . The process control and/or automation network as in  claim 4 , wherein a wireless router in the field network set containing the junction box is configured for wired communication and is wired to the junction box. 
     
     
         6 . The process control and/or automation network as in  claim 5 , wherein the wireless router that is wired to the junction box is a wireless intermediate device. 
     
     
         7 . The process control and/or automation network as in  claim 5 , wherein the wireless router that is wired to the junction box is a wireless gateway device. 
     
     
         8 . The process control and/or automation network as in  claim 1 , wherein the routing table stored in memory of the wireless router specifies, for each wireless end device, a predetermined number of assigned paths from the wireless end device to the master gateway device per usage class, the wireless router further storing a frame selection module executable by the processor of the wireless router that, upon receipt of a packet to or from a wireless end device, permits transmission of the packet along the assigned path if the router is within that particular assigned path, or drops the packet if the wireless router is not in the assigned path. 
     
     
         9 . The process control and/or automation network as in  claim 1 , wherein the routing table stored in memory of the wireless router specifies, for each wireless end device, a predetermined number of assigned and alternate paths from the wireless end device to the master gateway device per usage class;
 the wireless router further storing a frame selection module executable by the processor of the wireless router that, upon receipt of a packet to or from a wireless end device,
 permits transmission of the packet along the assigned path if the router is within that particular assigned path, or 
 permits transmission of the packet along the alternate path if the router is within that particular alternate path and there exists an exception in the network that requires use of the alternate path, or 
 drops the packet if the wireless router is not in the assigned or alternate path. 
   
     
     
         10 . The process control and/or automation network as  claim 2 , wherein at least one of the field network sets has at least one junction box,
 and wherein at least one of the wireless routers is configured for wired communication and wired to a junction box,   and wherein one of the wireless routers that is wired to a junction box is designated as an anchor packet selection device through which all traffic in that field network set is routed.   
     
     
         11 . The process control and/or automation network as in  claim 10 ,
 wherein the routing table stored in memory of the wireless router specifies, for each wireless end device, a predetermined number of assigned paths from the wireless end device to the master gateway device per usage class, the wireless router further storing a frame selection module executable by the processor of the wireless router that, upon receipt of a packet to or from a wireless end device, permits transmission of the packet along the assigned path if the router is within that particular assigned path, or drops the packet if the wireless router is not in the assigned path;   wherein the anchor packet selection device of each network set and for each tier further includes a packet selection module executable by the processor of the anchor packet selection device to select a packet among plural packets of the same information with the highest quality for retransmission;   and wherein the frame selection module receives the best packet from the packet selection module and transmits at least one copy of the best packet in the assigned paths toward the destination or the next tier.   
     
     
         12 . The process control and/or automation network as in  claim 11 , wherein the packet selection module implements a low density parity check. 
     
     
         13 . The process control and/or automation network as in  claim 11 , wherein the packet selection module implements a load balancing protocol to distribute traffic among various wireless routers in the field network set. 
     
     
         14 . The process control and/or automation network as in  claim 11 , wherein the packet selection module implements
 a low density parity check and   a load balancing protocol to distribute traffic among various wireless routers in the field network set.   
     
     
         15 . The process control and/or automation network as in  claim 2 , wherein at least some of the wireless routers in a field network set include a wireless router wired to a junction box which contain stored in their memories field network set information as to which wireless routers are wired to junction boxes and their respective performance characteristics, the wireless routers having field network set information further comprising a routing module that uses the field network set information to dynamically route packets within the field network set. 
     
     
         16 . The process control and/or automation network as in  claim 2 , wherein at least some of the wireless routers in a field network set include a wireless router wired to a junction box, wherein field network sets including a wireless router wired to a junction box are wired to the central control room. 
     
     
         17 . The process control and/or automation network as in  claim 16 , wherein the field network sets including a wireless router wired to a junction box include a designated junction box that is wired to the distributed control system in the central control room. 
     
     
         18 . The process control and/or automation network as in  claim 16 , wherein the wired connection is through a marshalling cabinet. 
     
     
         19 . The process control and/or automation network as in  claim 16 , wherein the wired connection is through a junction box router. 
     
     
         20 . The process control and/or automation network as in  claim 1 , further comprising a plurality of field network sets spanning across multiple tiers, each field network set containing one or more of the plurality of wireless routers and one or more wireless gateway devices, wherein the routers and gateway devices of each field network set act as a single routing device to route packets to routers and gateway devices external to the field network set. 
     
     
         21 . The process control and/or automation network as in  claim 20 , further comprising at least one marshalling cabinet and at least one junction box, the at least one junction box within one of the field network sets and wired to the marshalling cabinet for communication. 
     
     
         22 . The process control and/or automation network as in  claim 21 , further comprising a junction box router in wired communication between the junction box and the marshalling cabinet and in wired communication with the master gateway device. 
     
     
         23 . The process control and/or automation network as in  claim 22 , wherein a wireless router in the field network set containing the junction box is configured for wired communication and is wired to the junction box. 
     
     
         24 . The process control and/or automation network as in  claim 23 , wherein the wireless router that is wired to the junction box is a wireless intermediate device. 
     
     
         25 . The process control and/or automation network as in  claim 5 , wherein the wireless router that is wired to the junction box is a wireless gateway device.