FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION (See section 10, rule 13)
“CROSS LAYER PROTOCOL BASED WANET AND METHOD THEREOF FOR CONTROLLING COMMUNICATION OF PROCESS
FLOW PARAMETERS”
BITS Pilani, K K Birla Goa Campus of BITS Pilani, K K Birla Goa Campus, Zuarinagar, Goa, Maharashtra, 403726, India
& GAIL India Limited of Cabin no: 11923, GAIL Jubilee Tower, B-35 & 36, Sector-1, Noida, Utter Pradesh, 201301, India

FIELD OF THE DISCLOSURE
The present invention relates to a system and method for controlling communication/transmission of pipeline parameters from various remote locations to a central control unit using a wireless ad-hoc network (WANET).
BACKGROUND OF THE DISCLOSURE
Water, petroleum and natural gas resources have become important assets and maintaining the economic progress of the country is strongly depends on protecting these resources and facilities. One of the main and important facilities for these resources is the pipelines used to transfer water, petroleum, and natural gas. Water, Oil, and gas pipelines are considered one of the main infrastructures in many countries. The safety and security of this pipeline system is very important to prevent catastrophes that result in pollution, death, injury, or destruction of property/resource. Therefore, protecting the pipeline infrastructure by continuously monitoring the pipeline parameters is one of the important priorities. There are a number of technologies to monitor pipelines are conventionally available. Most of the technologies are designed specifically for detecting and locating pipeline leakages. These technologies were designed to provide a remote facility to detect and to report the positions of any leakage.
Some of these technologies monitor a gas/Liquid hydrocarbons (LHC) transport pipeline parameters by controlling transmission of data associated with the pipeline parameters from various flow computers located at remote customer sites to central locations such as control room /Terminals/Remote Control Unit (RTU) through various means such as hard wire (OFC cables) or GSM modems or Internet. These solutions rely on the availability of a network to transfer the information and report the leakages. The wire-based monitoring systems suffer from damages within any part of the network and the deployment in underground settings is highly costly. There are a number of problems using wired networks with regular sensors for monitoring pipelines and its parameters. One of the main problems is, if there is any damage for any part of the wires of the network, the whole pipeline monitoring system will be compromised. Further, it is easy for unauthorized people to disable the monitoring system by cutting the network wires. Also, it is

difficult to locate the position of the fault in a wire. This problem is more difficult with underground pipelines.
The main disadvantage of GSM, GPS, internet-based system is the absence of communication infra-structure in particular areas. Also, the setup and running cost of such a system was very huge. There are several problems being faced with the current data communication like limited/no network availability at remote sites, disturbances in the areas near to inter-state borders, OFC’s cuts, equipment failures etc., leading to the increased downtime of data acquisition. Furthermore, the conventional methodology to monitor pipeline parameters at the customer side varies with the type of flow computer and the type of interconnects i.e., MODBUS, EPL, SERCOS, Ethernet-IP.
Hence, there is a need to have a system and method that can overcomes the aforesaid problems, difficulties and disadvantages of the conventional technology or methodology and provide cost effective, reliable, non-obtrusive and efficient way of monitoring data by controlling transmission of the data associated with the process parameters of transport pipeline from various remote location of flow computers to central location and that can support for multiple types of flow computer with multiple industrial network standard without requiring any type of modifications to existing set-up at the customer side and also has support for legacy flow computers that are already pre-installed at customer site.
SUMMARY OF THE DISCLOSURE
One aspect of the present disclosure relates to a system and method for controlling transmission data associated with a gas/Liquid hydrocarbons (LHC) transport pipeline from flow computers located at various locations to central station using a cross layer protocol stack based wireless ad-hoc network (WANET). In an embodiment, the present invention discloses a method of formation of hierarchical structure of the said WANET using a cross layer protocol stack. Particularly, the present invention discloses the method of formation of hierarchical structure of the WANET by disclosing a method to add one or more new nodes into a wireless ad-hoc network (WANET) for transmitting data to a remote station or central unit. One such method comprises providing, an address to the remote station and setting the address as a root node address of the wireless ad-hoc

network, wherein the address comprises a node level and a node ID; broadcasting, by the one or more new nodes, a network join request to join the wireless ad-hoc network; transmitting by each of the nodes in the wireless ad-hoc network, a network join response comprising a node level corresponding to the transmitting node and an available address list to the one or more new nodes in response to the request, wherein the network join response is sent by the nodes which receive the broadcasted request; selecting, by the one or more new nodes, an address from the available address list based on the received node level from the responses; and registering, by the one or more new nodes, the selected address with the available address list provider node.
In another aspect, the present invention discloses a system for transmitting the data associated with a gas/Liquid hydrocarbons (LHC) transport pipeline from flow computers located at various locations to central station through the WANET. Said system comprises a short-range communication module comprising a microcontroller coupled to a short-range antenna; and a long-range communication module comprising a microcontroller coupled to a long-range antenna; wherein the short-range communication module and long-range communication module are operatively coupled such that the short-range communication module of a transmitting node from the plurality of nodes is configured to transmit data to the long-range communication module of the transmitting node; the long-range communication module of a receiving node from the plurality of nodes is configured receive the data from the long-range communication module of the transmitting node and transmit the data further to the short-range communication module of the receiving node.
BRIEF DESCRIPTION OF DRAWINGS
In order that the invention may be readily understood and put into practical effect, reference will now be made to exemplary embodiments as illustrated with reference to the accompanying drawings, where like reference numerals refer to identical or functionally similar elements throughout the separate views. The figures together with a detailed description below, are incorporated in and form part of the specification, and serve to further illustrate the embodiments and explain various principles and advantages, in accordance with the present invention where:

Figure 1 illustrates a hierarchical diagram of a cross layer protocol stack based WANET (Wireless Ad-hoc Network) comprising plurality of nodes.
Figure 2 illustrates a flow chart for the method of adding one or more new nodes in the WANET of Fig. 1.
Figures 3a & 3b illustrates a block diagram of a communication system inbuilt within each node of WANET as illustrated in Fig. 1.
Skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements to help to improve understanding of the aspects of the present invention.
DETAILED DESCRIPTION OF THE DISCLOSURE
Various embodiments and aspects of the invention will now be described here in detail with reference to the accompanying figures. The terminology and phraseology used herein is solely for descriptive purposes and should not be construed as limiting in scope. Language such as “including”, “comprising”, “having”, “containing” or “involving”, and variations thereof, is intended to be broad and encompass the subject matter listed thereafter, equivalents, and additional subject matter not recited. Exemplary embodiments of the invention will now be described in detail with reference to accompanying figures, in which like elements may be denoted by like reference numerals for consistency.
Overview of the present disclosure:
The present disclosure relates to a system and method for controlling communication of data associated with a gas/Liquid hydrocarbons (LHC) transport pipeline from flow computers located at various locations to central station using a cross layer protocol stack based wireless ad-hoc network (WANET). The cross layer protocol based ad-hoc network described in the present invention may be one from a group comprising a machine to machine network and a wireless sensor network. The cross-layer protocol stack is position –dependent in terms of position of a

given node in the hierarchy level of said WANET, as well as, its placement in the deployment pattern in the pipeline – the deployment in turn depends on the layouts of the pipeline and access to various communication points on the pipeline. The number of layers in the hierarchy is determined by the distance of the pipeline to be covered and number of process plant units that have to be covered and the distances between them. In an embodiment, the Cross Layer Protocol Stack stored in the controller unit has various algorithms such as for addressing, energy management, time synchronization, topology control, Media Access, Clustering, Routing and Application Interface. The Protocol stack also has algorithms to interface with standard industrial protocols as well. All these protocols perform best in tandem with each other while it has been implemented in the system as depicted in Fig. 3a & 3b.
Addressing is based on position of the node on the pipeline and its position in the hierarchy- as new nodes join the WSN an automatic address assignment follows node discovery. This is also explained in detail in the foregoing paragraphs. Topology Control is done through a sleep-wake pattern that is based on the address of the node. This sleep wake pattern has been implemented to increase energy efficiency and prevent over emission. This is also explained in detail in the foregoing paragraphs. At the physical Layer a frequency hopping pattern that is linked to the address of the node is followed. This ensures security in the network. Energy Level of transmission is variable based on node and neighbor discovery. The address of the node is functional and may be modified based on the network dynamics especially change in hierarchy due to dynamic clustering. Clustering is done based on energy levels and the position of the node on the pipeline – Nodes may be dynamically promoted or demoted on the multiple hierarchical layers based on the clustering algorithm results. The hierarchy itself can be dynamic in nature with varying levels depending upon the geographical area to be covered. As this is a hybrid WSN data is collected at regular intervals of time- this time parameter configurable at any level of the hierarchy – data collected is aggregated at different levels of the hierarchy – aggregation pattern is configurable – aggregated data is convegecasted to multiple points in the network hierarchy – other than time triggered data – soft thresholds are used to choose the time intervals to convergecast data. Hard Thresholds are used to convergecast data in case of events. List of events can be reconfigured at any point time at any level of the hierarchy. List of events can be specified separately for different

segments of the pipeline or for different units of the Process plants or for individual customers. The same variations can also be introduced for the soft threshold.
The Media Access protocols is a Dynamic Hybrid TDMA/FDMA/CSMA variant. The time slots and frequency of transmission are determined by the addressing and priority of data that needs to be transmitted. A neighbour discovery protocol is integrated with the MAC protocol – the neighbour address is the main factor that is required to derive information about the neighbour. Routing is hierarchical, address-gradient based. A process of attraction and repulsion is used to set up an address gradient based route towards the destination(s). The Routing Protocol is self-healing and fault tolerant. Application layer provides user interface to custom GUI as well as to standard industrial protocols – this is again selectable. Time synchronization is both sender- multiple receiver time synchronization variant. Time synchronization is hierarchical and is embedded with the data communication for a reduced overhead. Message format for communication of data and control information have also been defined.
The cross-layer network protocol stack also supports querying with varying, Scope, Time – to – Live and Objective. The type of queries that are supported by the network need not all be specified at time of initialization and configuration. The query can be addressed either to the centralized or distributed database or can be used for real –time data gathering. In-Network programming that allows variation in network protocol stack – and used for network maintenance and variation in data collection patterns and purpose is supported at all levels of the hierarchy. Message Format to support the same has been developed.
The network does not require any additional infrastructure structure such as GPRS/GSM, 3G/4G or satellite networks and is completely ad hoc and hence can also be deployed in areas where there is no access – rural, underground or underwater. The frequency used though is ISM does not suffer from interference from other wireless network and hence is also suitable for urban areas. The hardware for implementing this protocol stack is also part of the invention and can be interfaced to any sensor that is used in gas pipeline, gas process plant or at the customer end. It supports sensors with digital, frequency or analog outputs. It can also be interfaced to any industry standard bus and can act as independent data collection unit. The hardware also is capable of short, medium

and long-range communication (communication range between 50m to 10km) can be used in hostile environments and store several MB of data independently. It can connect only with other similar hardware to form a co-operative network using the algorithms described above.
Detailed Explanation of the Drawings:
An exemplary embodiment showing hierarchical diagram of a WANET comprising plurality of nodes is depicted in Fig. 1. As shown in the Figure 1, the system head represents a root node which is a central station placed at the level 1 of the hierarchy of this WANET. This central station may also be called as control station or central gathering station or central unit. It may be noted that it has Id: 0 for this exemplary embodiment. There may be three nodes represented by section heads having ids 1, 2 and 3 respectively are in immediate connection with the central station at level 2 of the hierarchical structure. Similarly, there may be 2 more nodes represented by section heads having ids 1.1 and 1.2 respectively are in immediate connection with the section head of level 2 with id 1. It may be noted that the node represented by section head of level 3 with id 1.1 is in immediate communication with a couple of nodes having ids 1.1.1 and 1.1.2 respectively at its lower level (i.e., at level 4). Similarly, the node represented by section head of level 3 with id 1.2 is in immediate communication with a node having id 1.2.1 at its lower level (i.e., at level 4). Thus, a node in the hierarchical level of WANET may be identified using its address which comprises a level and id. The above process is the initialization process.
It may be noted that the above exemplary embodiment is intended to be described and depicted above only for the purpose of understanding and it never limit its scope of this invention.
It may be noted that the initialization process also includes a process or method of adding one or more new nodes in the WANNET. Fig. 2 depicts flow chart for the method of adding one or more new nodes in the WANET. Accordingly, block 101 represents a step of allocating assigning address to a remote station or root node. This step also includes the step of allocating address to all the existing nodes in the WANET. Block 102 represents that when one of more new nodes try to add into the WANET, it initially broadcasts its network joining request to join into the WANET. Upon broadcasting this request, as directed in block 103, each of the nodes in the WANET

transmits a network join response comprising a node level corresponding to the transmitting node and an available address list to the one or more new nodes. Wherein the network join response is sent by the nodes which receive the broadcasted request. Upon transmitting this response, as depicted in block 104, the one or more new nodes selects an address from the available address list based on the received node level from the responses. In some embodiment, the one or more new nodes may consider a response for addition to the wireless ad-hoc network only when the response signal strength is above a predefined threshold. In some another embodiment, when multiple responses are received from the nodes corresponding to the same level, the one or more new nodes may connect to the node from which response is received earlier. Upon selecting the said address, as depicted in block 105, the one or more new nodes register selected address with the available address list provider node and thereby becomes a member of the WANET. Thus, the nodes in the WANET may be added horizontally and/or vertically in a hierarchical manner as depicted in Fig. 1. In an alternate embodiment any nodes in the WANET may also be subtracted/removed. If node(s) is/are removed then address will be made available after some time.
Say for an instance, if section head of level 2 having node id: 01 as depicted in Fig. 1 disappears/removed then the section heads of level 3 having node ids 1.1 and 1.2 may be connected/rejoined either to section head of level 2 having node id: 02 or to section head of level 2 having node id: 03 based on distance. This process of rejoining is performed by rebroadcasting a network join request by the section heads of level 3 having node ids 1.1 and 1.2 to re-join the WANET. Meanwhile, the address associated with level 2 having node id: 01 becomes available and the same is added into the address list maintained by the system head of level 1 having node id: 0. In this way every node will have two ques 1) available address and 2) assigned address.
Upon completing the initialization process, the step of time synchronization starts where the time sync starts from the root node and moves downwards towards all the nodes of the WANET. The root node sends its time stamp and propagation delay is estimated and time updated on next level. Upon completion of time sync step, steps of data collecting and data transmitting from the nodes starts. Such a method for collecting and transmitting data by a node, over the wireless ad-hoc network comprises: aggregating data from each of node connected to the node at a lower level in

a hierarchical manner; packetizing, the aggregated data; and transmitting the packetizing data over the wireless ad-hoc network.
In case when the size of the packetized data to be transmitted above a predefined threshold determined based on a maximum transmission unit, the data collection and transmission method further comprises: fragmenting said packetized data; and transmitting said fragmented data using flow control. Also, it may be noted that in an embodiment, each node of the wireless ad-hoc network is configured to enter sleep mode for a predefined time period and wherein the sleep schedule of each node is transmitted to all other nodes connected at the immediate lower level, and the predefined time for nodes of a lower level elapses before the elapsing of the predefined time for nodes of an immediate higher level. In some another embodiment, the each of the said node may be configured to: auto-disable the sleep mode upon determination that that the variation between two consecutive data values is above a predetermined threshold; and auto-re-enable sleep mode upon determination variation between the most recent data to be transmitted and the data preceding the crossing of the first predetermined threshold is below the predefined threshold.
In an embodiment, the data may be transmitted continuously upon determination that that the variation between two consecutive data values is above a predetermined threshold; and a short message indicating the data to be transmitted may be transmitted upon determination that the variation between two consecutive data values is below the predetermined threshold. This enables in saving the energy/power since entire message is not sent but only a short message indicating that data is same is sent. In some another embodiment the date is continuously transmitted until a variation between the most recent data to be transmitted and the data preceding the crossing of the first predetermined threshold is determined as being below the predefined threshold.
Fig. 3a and Fig. 3b illustrates a block diagram of a communication system inbuilt within each node of WANET as illustrated in Fig. 1 of this disclosure. Each nodes of the Fig. 1 communicate with each other using the said communication system in order to transmit data to the root node. The system comprises a short-range communication module (300) as illustrated in Fig. 3a and a long-range communication module (400) as illustrated in Fig. 3b. The short-range communication module further comprises a flow computer (302), a controller unit (303), a short-range transmitting

module (304) having a transmitting antenna (305). In a given embodiment the controller unit may be ATMEGA 328P controller and the short-range transmitting module (304) may be a XBee module. The flow computer (302) is configured to receive and display the data associated with the process parameters from a transport pipeline. The process parameters may include but not limited to flow rate, gas chromatograph data, temperature data, pressure data. The controller unit (303) coupled to the flow computer is configured to store the cross-layer protocol stack and controls to drive the entire system based on the said protocol stack. Accordingly, the controller unit (303) configured to receive the data associated with the process parameters though a mod bus interface and relaying it to the short-range transmitting module (304) though an RS232 interface for transmitting data internally within the node via an antenna (305). The short range receiving module
(402) receives the transmitted data from the antenna (305) and relay the same to the controller unit
(403) of long range communication module (400) and from where the data is finally transmitted externally outside the node using the long-range communication module (404) and antenna (404).
It may be noted that the above features of Fig. 3a & 3b are explained to the context of considering that the node/system is transmitting data from the flow computer. However, a person skilled in the art may well aware that the similar operations in Fig. 3a and 3b may also be carried out to the context of receiving node that receive the transmitted data from the transmitting node. Therefore, the same is avoided here for the sake of brevity.
The control unit or controller mentioned in the disclosure may include a memory and a processor coupled with the memory. The memory configured to store a specific logic or instructions and the processor may execute or perform the instructions or logic to carry out the similar functionalities or operations of control unit as described in the disclosure. Further, the said processor may include a general purpose processor, a digital signal processor (DSP), an application specific integration circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the function described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be a controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a

combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.
Further, the memory may include any storage media which can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be acceded by computer or the processor as mentioned above.
The foregoing detailed description has described only a few of the many possible implementations of the present invention. Thus, the detailed description is given only by way of illustration and nothing contained in this section should be construed to limit the scope of the invention. The claims are limited only by the following claims, including the equivalents thereof.

We Claim:
1. A method to add one or more new nodes into a wireless ad-hoc network (WANET) for
transmitting data to a remote station comprising:
providing, an address to the remote station and each of the existing nodes in the WANET, and setting the address of the remote station as a root node address, wherein the address comprises a node level and a node ID;
broadcasting, by the one or more new nodes, a network join request to join the wireless ad-hoc network;
transmitting by each of the nodes in the wireless ad-hoc network, a network join response comprising a node level corresponding to the transmitting node and an available address list to the one or more new nodes in response to the request, wherein the network join response is sent by the nodes which receive the broadcasted request;
selecting, by the one or more new nodes, an address from the available address list based on the received node level from the responses; and
registering, by the one or more new nodes, the selected address with the available address list provider node.
2. The method as claimed in claim 1, further comprising upon detection of non-working of a node from the WANET, rebroadcasting by nodes at the immediate lower level to said node, a network join request to re-join the WANET.
3. The method as claimed in claim 1, further comprising upon detection of non-working of a node from the WANET, re-adding, by the node connected at the immediate higher level to said node, the address associated with said node into the address list.
4. The method as claimed in claim 1, wherein the address is selected from the address list provided by a node at a higher level from among the received responses.
5. The method as claimed in claim 1, wherein the one or more new nodes consider a response for addition to the wireless ad-hoc network when the response signal strength is above a predefined threshold.

6. The method as claimed in claim 2, wherein when multiple responses are received from the nodes corresponding to the same level, the one or more new nodes connects to the node from which response is received earlier.
7. The method as claimed in claim 1, wherein the ad-hoc network is one from a group comprising a machine to machine network and a wireless sensor network.
8. The method as claimed in claim 1, wherein each node of the ad-hoc wireless network is time synchronised.
9. A method for transmitting data by a node, over the wireless ad-hoc network as claimed in 1, comprising:
aggregating, by the node, data from each of node connected to the node at a lower level;
packetizing, the aggregated data; and
transmitting the packetizing data over the wireless ad-hoc network.
10. The method as claimed in claim 9, wherein when the size of the packetized data to be
transmitted above a predefined threshold determined based on a maximum transmission
unit, the method further comprises:
fragmenting said packetized data; and
transmitting said fragmented data using flow control.
11. The method as claimed in claim 1, wherein each node of the wireless ad-hoc network is configured to enter sleep mode for a predefined time period and wherein the sleep schedule of each node is transmitted to all other nodes connected at the immediate lower level.
12. The method as claimed in claim 11, wherein the predefined time for nodes of a lower level elapses before the elapsing of the predefined time for nodes of an immediate higher level.

13. The method as claimed in claim 9, wherein data is associated with a gas/Liquid hydrocarbons (LHC) transport pipeline wherein the data comprises one or more from a group comprising: flow rate, gas chromatograph data, temperature data, pressure data.
14. The method as claimed in claims 9-13, wherein:
data is transmitted continuously upon determination that that the variation between two consecutive data values is above a predetermined threshold; and
a message indicating the data to be transmitted is transmitted upon determination that the variation between two consecutive data values is below the predetermined threshold.
15. The method as claimed in claim 14, further comprising continuously transmitting the data, until a variation between the most recent data to be transmitted and the data preceding the crossing of the first predetermined threshold is determined as being below the predefined threshold.
16. The method as claimed in claim 11, wherein each node is configured to:
auto-disable sleep mode upon determination that that the variation between two consecutive data values is above a predetermined threshold; and
auto-re-enable sleep mode upon determination variation between the most recent data to be transmitted and the data preceding the crossing of the first predetermined threshold is below the predefined threshold.
17. A System of Wireless Ad-hoc Network (WANET) comprising a plurality of nodes,
wherein each of the plurality of nodes comprises:
a short-range communication module comprising a microcontroller coupled to a short-range antenna; and
a long-range communication module comprising a microcontroller coupled to a long-range antenna;
wherein the short-range communication module and long-range communication module are operatively coupled such that
the short-range communication module of a transmitting node from the
plurality of nodes is configured to transmit data to the long-range
communication module of the transmitting node;

the long-range communication module of a receiving node from the plurality of nodes is configured to receive the data from the long-range communication module of the transmitting node and transmit the data further to the short-range communication module of the receiving node.
18. The system as claimed in claim 1, wherein the WANET is a cross layer protocol based WANET.