Method and system for irrigation control

[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 12/537,772, filed on Aug. 7, 2009, entitled Method And System For Remote Wireless Monitoring And Control Of Climate In Greenhouses, which is hereby incorporated by reference, and which claims priority to Turkish Patent Application No. 2008/05998, filed on Aug. 12, 2008, entitled REMOTE WIRELESS CLIMATE MONITORING AND CONTROL SYSTEM FOR GREENHOUSES, and to Turkish Patent Application No. 2009/00883, filed on Feb. 5, 2009, entitled, REMOTE WIRELESS CLIMATE MONITORING AND CONTROL SYSTEM FOR GREENHOUSES.

[0002] The present invention relates generally to methods and systems for monitoring and controlling irrigation and climate conditions in landscapes (such as, e.g., municipal parks, gardens, and sports fields) and agricultural environments (such as, e.g., open agricultural fields, greenhouses, and other sites growing crops).

[0003] Irrigation systems supply water to soil. They are primarily used to assist in the growing of agricultural crops and maintenance of landscapes. Irrigation systems typically include valves, controllers, pipes, and emitters such as sprinklers or drip tapes. Irrigation systems can be divided into zones because there is usually not enough pressure and available flow to run sprinklers or other water emitting components (e.g. drip tapes) for an entire yard, sports field, or other irrigation site at once. Each zone has a solenoid valve that is controlled via a typically wired connection by an irrigation controller. The irrigation controller is either a mechanical or electrical device that signals a zone to turn on at a specific time and keeps it on for a specified amount of time or until it gets turned off manually.

[0004] Branch pipes in each zone are fed by a main line or common supply pipe. Valves are either controlled manually by a person or electronically by a solenoid that is connected to a controller. In existing systems, controllers are typically wired to the solenoid valves and the energy/power to actuate them is provided through wires. Controllers can decide to turn on/off valves based on schedules, weather information, and/or sensor readings. Water can be pumped into the main line from a well source or a city supply.

[0005] A “smart controller” is a controller that is capable of adjusting the watering time by itself in response to current environmental conditions. Smart controllers determine current conditions using historic weather data for the local area, soil moisture sensors (water potential or water content), weather stations, or a combination of these.

[0006] Weather based smart controllers for irrigation can provide the appropriate watering schedule, adjust for weather changes, and irrigate based on the needs of the field and/or landscape. A smart controller will automatically reduce the watering times or frequency as the weather gets cooler and less water is needed. Then, as the weather begins to warm up, the controller will add more watering time or increase the watering frequency.

[0007] Evapotranspiration (ET) is the rate of water loss from the field or other irrigation site. It is nature's process for transferring moisture to the atmosphere by the evaporation of water from the soil and transpiration of water from plant surfaces. ET measurements can be used for determining crop irrigation needs.

[0008] A wireless system is provided in accordance with one or more embodiments for monitoring environmental, soil, or climate conditions and controlling irrigation or climate control systems at an agricultural or landscape site. The wireless system includes a wireless sensor network including a plurality of sensor nodes for monitoring environmental, soil, or climate conditions and controlling one or more irrigation or climate control systems at the site. The wireless system also includes a server computer system located remotely from the site. The server computer system is coupled to the wireless sensor network over a communications network for receiving data from and controlling operation of the sensor nodes. The server computer system is also coupled to a device operated by an end-user over a communications network for transmitting the data to and receiving remote control commands or queries from the end-user.

[0009] A method is provided in accordance with one or more embodiments of controlling irrigation or climate control systems at an agricultural or landscape site. The method includes communicating with a wireless sensor network installed at the site over a communications network. The wireless sensor network comprises a plurality of sensor nodes for monitoring environmental, soil, or climate conditions and controlling one or more irrigation or climate control systems at the site. Communicating with the wireless sensor network comprises receiving data from and controlling operation of the sensor nodes. The method further includes communicating with a device operated by an end-user over a communications network for transmitting the data to and receiving remote control commands or queries from the end-user.

[0010] Various embodiments of the invention are provided in the following detailed description. As will be realized, the invention is capable of other and different embodiments, and its several details may be capable of modifications in various respects, all without departing from the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature and not in a restrictive or limiting sense, with the scope of the application being indicated in the claims.

[0021] In accordance with one or more embodiments of the invention, a wireless monitoring and control system is provided for irrigation and climate management for landscapes and agricultural environments. The system includes a wireless sensor network comprising a plurality of sensor nodes for monitoring environmental, climate, and soil conditions and controlling one or more climate control systems and/or irrigation valves and pumps. The system also includes a server computer system located remotely from the irrigation site. The server computer system is coupled to the wireless sensor network over a communications network for receiving data from and controlling operation of the sensor nodes. The server computer system is also coupled to a device such as a cell phone or a personal computer operated by an end-user over a communications network for transmitting the data to and receiving remote control commands or queries from the end-user.

[0022] An irrigation control system in accordance with one or more embodiments can include one or more of the following components:

• • [0023] a. Field hardware
    • [0024] i. Sensors such as soil moisture probes, water flow meters, water pressure gauges, and ambient temperature and humidity probes
    • [0025] ii. Devices such as water valves and pump motor control relays
    • [0026] iii. Wireless sensor nodes that make up the wireless sensor network
    • [0027] iv. Wireless special function nodes such as meteorology station nodes and well control node
    • [0028] v. Wireless gateway that connects field equipment to a computer server
  • [0029] b. Wireless sensor network firmware that runs on sensor nodes
  • [0030] c. Computer server located remotely from the irrigation/climate control site
  • [0031] d. Application running on an end-user device (e.g., a cell phone application) for communicating with the computer server
  • [0032] e. Web-based application running on the computer server for user interaction and data access

[0033] In accordance with one or more embodiments of the invention, a method of monitoring and controlling irrigation and/or climate conditions in landscapes and agricultural environments is provided. The method includes communicating with a wireless sensor network installed in the irrigation/climate control site over a communications network. The wireless sensor network comprises a plurality of sensor nodes for monitoring environmental, climate and soil conditions in the site and controlling one or more climate and/or irrigation control systems such as solenoid valves and pumps. Communicating with the wireless sensor network comprises receiving data from and controlling operation of the sensor nodes. The method also includes a step of communicating with a device such as a cell phone or a personal computer operated by an end-user over a communications network for transmitting the data to and receiving remote control commands or queries from the end-user.

[0034] The organizational hierarchy of an irrigation system in accordance with one or more embodiments can have multiple levels. For example it can be four levels deep as shown in the exemplary system of FIG. 7. In smaller sites, partitioning to master zones may not be required. A site may be handled by one or more gateway nodes. A zone is handled by one or more sensor nodes. If there is a need to connect sensors or devices to a master zone, such as a master zone water valve, then a sensor node is used for this master zone. Special nodes, such as a meteorology station, can serve all nodes of the whole site. Sensors and devices are generally connected to the sensor nodes. However, if needed, additional sensors and devices may also be connected to the gateway node if required.

[0035] To compute the irrigation requirements for plants at a given irrigation site (e.g., field or landscape), daily ET data gathered from onsite wireless sensor nodes and/or from a weather station at or close to the site can be used in combination with information entered by end-users into the website about crops and other plants. Using these inputs, the system can compute an accurate watering schedule for each zone at the irrigation site and adjust or update each zone's schedule as needed on a daily basis. The wireless sensor nodes controlling the irrigation valves can get the updated schedule from the server.

[0036] The system compares the ET measurements with the soil moisture readings (e.g., water volumetric content or water potential) taken from wireless sensor nodes. If the difference is greater than a given threshold value defined by the end user, the system adjusts the schedule based on soil moisture probe readings.

[0037] In addition, the system can collect actual irrigation information through flow meters or sensors attached to wireless sensor nodes. In this way, the system can compare what is scheduled versus what was actually applied. There may be a difference if the valves are controlled manually and/or if there are problems or leaks in the irrigation system (e.g., in the pipes, valves etc.). Based on the actual irrigation amounts, the system can adjust the irrigation schedule going forward, e.g., for the following 7 days.

[0038] In accordance with one or more embodiments, the system integrates public weather forecast information. The server checks for the rain forecast and decides whether or not to delay an upcoming irrigation event based on the amount of expected rain, the likelihood of rain event, and calculated and/or measured plant needs.

[0039] The system in accordance with one or more embodiments offers an on-demand irrigation capability. Soil moisture as well as ET calculations may be used to schedule irrigation. Those calculations may be used to determine a schedule. A system that solely depends on soil moisture readings and controls irrigation based on two thresholds to start and stop at would be considered an on-demand irrigation.

[0040] When on-demand irrigation is followed, irrigation control decisions are made by nodes intelligently, and not by the server. In this way, latency in receiving commands from server is eliminated (except when user sends manual commands). In addition, there is no need for delegated irrigation programs running on the server because the schedule and/or control condition is always on the node and the node decides based on this information.

[0041] When an on-demand irrigation technique is used, the server is used as a means of interfacing with the network and manages two way data communication. Rules/conditions are stored on devices for execution and server for redundancy.

[0042] In accordance with one or more embodiments of the invention, operation of any valve in the system may be overridden by a manual command. Independent of the state of the valve according to the current scheduled irrigation program, it may be forced to turn on or turn off. A valve will stay in this manual override position irrespective of the status that is demanded by the irrigation program for that time of day. A manually issued “resume” command will return control of that valve back to the irrigation program where the valve will be set to the position as scheduled there.

[0043] In accordance with one or more embodiments, if a manual command is sent to node to turn a valve on or off, the node sends an acknowledgment to the server about execution and stores the unique ID associated with the control command. If the server does not receive the acknowledgement, it will retry to send the command with the same unique ID. When the node receives it the second time, it will not execute the command but re-acknowledge prior execution of the command to the server.

[0044] In one or more embodiments, an emergency override command is available to turn off all the valves in the system. This command may be issued during emergency conditions such as, e.g., an earthquake. After an emergency stop, individual valves may be manually turned on or off or resumed at will. An emergency resume command is also available where control of all valves are returned back to the current irrigation program.

[0045] In accordance with one or more embodiments, the server performs periodic health checks to see if all nodes are available and alerts users or tries to overcome the problem (such as soft reboot on root/node etc.).

[0046] A wireless climate monitoring and control system in accordance with one or more embodiments provides significantly improved scalability and reliability because information is transferred from sensor node to node and then to a remote central server computer system, and the wireless sensor network can reconfigure itself dynamically.

[0047] Furthermore, in a system in accordance with one or more embodiments, wireless sensor networks are used to collect climate and soil data and to control the irrigation. This system offers numerous advantages including wireless installation, flexibility, and scalability. Since additional sensor units can be easily and cost effectively implemented, it is possible to provide a large number of sensor nodes at a site. Having a greater number of sensor nodes helps provide a better understanding of micro-climates as well as soil moisture status, which can vary significantly in a field due to natural variability in the soil. The system accordingly provides improved accuracy on measurements, making micro-climate management possible. Due to micro-climatization, growth of small plant groups can be monitored and surrounding conditions can be adjusted accordingly.

[0048] In addition, multiple irrigation zones can be irrigated independently based on the sensor readings in the respective zone. Typically, as there may not be enough pressure on the main line, separate irrigation zones will not be irrigated at the same time. The system in accordance with one or more embodiments can perform scheduling of irrigation between zones for optimal irrigation efficiency. The scheduling can be based on a variety of considerations including, e.g., available water pressure and constraints defined by the end user including, e.g., zone prioritization based on crop importance.

[0049] A remote wireless monitoring and control system for irrigation in accordance with one or more embodiments includes a distributed control capability. Rather than one central controller or a server managing the irrigation control, distributed wireless sensor and control nodes run software that can execute the control decisions based on predetermined rules or schedule.

[0050] In a wireless climate and soil monitoring and control system in accordance with one or more embodiments of the invention, climate parameters (temperature, light, humidity, soil moisture, and leaf wetness etc.) measured by the sensors are stored in a server computer at a remote central location. Management and data storage on a central server as described herein reduces costs for the end users and makes the installation and remote management of the climate monitoring and control system easier. Remote control commands or control condition set values sent through the central server (from a cell phone or any computer on the Internet) are transmitted to wireless sensor nodes in the greenhouse or field, allowing manual and/or automatic control functionality.

[0051] In a system in accordance with one or more embodiments, data is transmitted from the sensor network to the main server computer through cellular networks or using broadband communication technology. In this manner, data coming from multiple sensor networks (sites) is consolidated and stored in a central computer server and then monitored/managed remotely through web, cell phone, or text message (SMS) applications.

[0052] A system in accordance with one or more embodiments allows monitoring climate conditions (temperature, humidity, light etc.) and controlling climate control systems inside the network by sensor nodes. In addition, it addresses how data collected by multiple sensor networks are stored in a central server and how control commands passing through this server are processed to manage the climate.

[0053] In a system in accordance with one or more embodiments, data is transferred from sensor networks to the central server through a cellular network or a wireless broadband communications technology. Data coming from a plurality of sites (local sensor networks) are consolidated and stored in the central computer server. Climate measurements taken are provided to the end users through web, cell phone, and/or text message (SMS, MMS, etc.) applications. Moreover, the system enables remote control commands to be sent to the irrigation site.

[0054] In one or more embodiments, climate parameters (temperature, humidity, light, soil moisture and leaf wetness etc.) can be continuously monitored and, for undesired values, automatic preventive actions can be taken before the products are harmed. For example, when flow sensors detect leakage excessive water on a pipeline, actuators can trigger the pump to shut down or main line solenoid valves to cut the water supply. Also, for any readings beyond pre-defined thresholds, the end user can be notified, e.g., by a short message (SMS, MMS, etc.) to his or her cell phone or via e-mail.

[0055] In accordance with one or more further embodiments, the computer server analyzes soil condition data received from the wireless sensor network and generates recommended upper and lower threshold values for starting and stopping irrigation. The computer server can recognize trends in soil moisture graphs or from moisture data and alert the user if conditions are unsatisfactory (e.g., if the area is over or under irrigated or if the soil moisture level is saturated) or if the roots are active and healthily pulling water from the soil. The user has the option of accepting or modifying the recommended values generated by the computer server.

[0056] Systems in accordance with one or more embodiments can be easily installed in open fields, landscapes, and greenhouses due to use of wireless and battery powered components. This reduces wiring costs and pollution. At the same time, since no computer system is installed within the site, the total system cost is reduced and maintenance is made easier.

[0057] An irrigation system in accordance with one or more embodiments provides a controlled irrigation and production environment that increases productivity in agricultural environments, reduces losses occurring because of frost and various diseases, and improves quality. One element of building such an environment is an automation system. Using automation systems, the climate within a greenhouse can be kept at generally ideal conditions for the plants, and irrigation within the greenhouse or open fields can be optimized based on crop needs thereby achieving generally maximum production performance. Systems in accordance with one or more embodiments of the invention make agricultural automation and irrigation control affordable, easy to use, and provide flexibility of use.

[0058] In accordance with one or more embodiments, nodes of the wireless sensor network can operate in sleep mode to reduce battery consumption. Sensor nodes wake up at certain time periods and listen to the signals to see if there is any data sent to them. If there is a signal with data addressed to them, they process the data or forward it to another node and then go to a sleep mode again by turning off their RF transmitter and receiver. Likewise, in certain periods, the sensor nodes take measurements and send it to either the main gateway (base station) or to the neighbor node with best data link quality. They then go back to a sleep mode after the transmission. A multi-hop structure (mesh networking) used in the sensor network increases the energy efficiency by keeping the RF signal power at lower levels. In addition to increasing energy efficiency by sending the data through other nodes across short distances, sensor nodes can easily extend the total coverage area with this structure.

[0059] With a mesh network structure in accordance with one or more embodiments, every node shares the information it has with all other nodes. This way, nodes can synchronize critical data among each other and can run control commands based on collaborative data.

[0060] Remote wireless climate, environmental, and soil monitoring and control systems in accordance with various embodiments thus provide a number of advantages. The systems provide improved scalability and reliability. The systems can allow usage of significantly larger number of sensor units. The systems can achieve high accuracy and micro-climatization, and address data reliability concerns due to soil variation. The systems can allow monitoring multiple irrigation zones and small plant groups and controlling the environment and irrigation accordingly. The systems can allow remote management of climate and soil monitoring and control system through Internet, cellular phone and/or SMS or MMS applications. The systems can reduce system and management costs for the end user. The systems can consolidate and store measurements coming from multiple sensor networks (at respective sites) on a central computer server. The systems can sense climate, environmental, and soil conditions (temperature, humidity, soil moisture etc.) and to control climate or irrigation systems in the network with the sensor nodes. The systems can enable wireless communication, monitoring, and management from far distances. The systems can enable the usage of a multi-hop dynamic network or mesh network structure. The systems can enable remote monitoring and control of wireless sensor networks in landscapes, open fields and greenhouses via a central computer server. The systems can reduce cable pollution and installation difficulties. The systems can provide capabilities to automatically prevent or reduce damages to plants from undesired climate values (temperature, humidity, light etc.) or irrigation inefficiencies. The systems can increase productivity in agricultural environments. The systems can prevent or reduce losses due to frost and various diseases. The systems can create a controlled production environment in order to increase product quality. The systems can achieve significantly improved production performance.

[0061] FIG. 1 illustrates the architecture of a wireless climate monitoring and control system for an irrigation/climate control site (e.g., greenhouse, open field, or landscape) 10 in accordance with one or more embodiments of the invention. The system includes a wireless sensor network 12 having a plurality of sensor nodes installed in the site 10. FIG. 2 schematically illustrates an exemplary wireless sensor network 12 in greater detail. The sensor network 12 includes sensor nodes S1-S16, which form an ad-hoc (i.e., dynamic) wireless sensor network and monitor climate, environmental, and soil conditions and collect measurements. The sensor nodes S1-S16 send these measurements to a central computer server 14 through a communications network 16 such as a cellular network (e.g., GPRS, Edge, UMTS etc.) or a wireless wideband network (e.g., WiMAX).

[0062] The central computer server 14 receives measurements and other data from a plurality of sites. The measurements/data collected from member sites are stored in a database on the central server 14. End users can access collected data over a web page on a device such as a personal computer 18 over the Internet 22 or through a cell phone application 20. The end users can use the same applications to send commands to the sensor nodes S1-S16 to trigger actuators for irrigation and/or climate control systems (e.g., heating, ventilation, misting units etc.) and provide manual and/or automatic remote control capability.

[0063] The sensor nodes S1-S16 installed in the site 10 support multiple sensor probes for measurements. These sensor probes include, but not limited to, ambient temperature and humidity, soil moisture, temperature and EC, solar radiation, leaf wetness, wind and rain.

[0064] The sensor nodes S1-S16 installed in the site 10 transfer the data they collect to a main gateway/base communication node 24 by relaying the data through other sensor nodes S1-S16 known as neighbor nodes. The sensor nodes S1-S16 identify their neighbor nodes based on signal quality. In particular, the sensor nodes S1-S16 identify nodes that provide the best quality data transfer link and transfer data through the neighbor with which the best quality data transfer link can be established. The neighbor node, which is used as a bridge, is called parent node. For example, as shown in FIG. 2, any node that receives data from another node is a parent node. For example, node S13 is the parent of node S16, and node S10 is the parent of node S13.

[0065] If there is a communication problem between a sensor node and its parent, the sensor node starts to use one of its other neighbors as its parent node. In this way, the sensor network 12 reconfigures or heals itself dynamically. Hence sensor nodes S1-S16 can easily be relocated to different spots in the site.

[0066] End users can operate devices such as a cell phone 20 having a cell phone application or short text message communication application or a personal computer 18 having a web application to facilitate communication with the central server 14 and retrieve information from the central site information and measurement database.

[0067] The wireless sensor network 12 includes a plurality of sensor nodes S1-S16, which have sensing (e.g., temperature, solar radiation, humidity, soil moisture, electrical conductivity etc.), processing and communication capabilities and can be battery operated and solar powered. The network 12 is generally used to monitor the environment and interact with the physical world.

[0068] The wireless sensor network 12 also includes a main gateway/base communication (root/sink) node 24, which is the main communication device where all data is collected and from which the data is transferred to the central computer server 14.

[0069] The central server or main computer 14 collects data from all member sensor networks. The central computer also distributes various data to member sensor networks. A software program that collects and processes data through Internet protocols such as TCP or UDP, and a database runs on this computer.

[0070] The climate, environmental, and the soil conditions in the site are monitored and controlled by using wireless sensor and control nodes S1-S16. Sensor nodes S1-S16 form an ad-hoc (dynamic) network as soon as they are installed in the site. Sensor nodes share collected sensor information (temperature, humidity, light, soil moisture, EC, PH, and CO₂ etc.) with each other and transmit to main gateway 24.

[0071] Communication between the wireless sensor network 12 in the site and the central server 14 is established by using, e.g., GPRS, Edge, 3G, UMTS or similar technologies over cellular network 16 or a wireless broadband data communication service such as WiMAX. Main gateway device 24 includes hardware for communicating with the wireless sensor network 12 at the site and the cellular network 16.

[0072] Data coming over the cellular network 16 is collected and transferred to central server 14 using the Internet 22 by using Internet protocols such as, e.g., TCP and/or UDP by the cell phone operator.

[0073] The central main server 14 is the central computer system where measurement data from various sites is collected and served to end users through the Internet 22 or by cell phone 20. At the same time, end users initially transfer the queries they will be sending to sites or system parameters like control conditions to the main server 14. Main computer server 14 transfers this information to the network in the site through channels as described below in FIGS. 3 and 4.

[0074] The system provides network management and monitoring capability through cell phones 20. End users can query the sensor readings inside the network by sending short text messages (SMS) or by using a client application installed on their cell phone 20. At the same time, end users can activate various climate control systems such as heating, ventilation, or misting through their cell phones 20 and ask for text message alerts to be delivered to their cell phones 20.

[0075] The system also provides network management and monitoring capability through a web enabled device 18. Data collected on sensor networks 12 is stored in a central database. Using a web application, this data is processed and served to the customer. At the same time, commands can be sent to nodes S1-S16 in the network 12 through this web application 18. Access to web application 18 is preferably restricted to end users or other users who are authorized by the owner.

[0076] One or more embodiments of the invention are directed to setting up a wireless sensor network 12 in the site and sensor node features and placement techniques.

[0077] Wireless sensor nodes S1-S16 can be placed some distance apart, e.g., with a distance of 30 m to 2000 m between each other. Depending on the structure of the greenhouse or the open field terrain, the construction type/material or the type of the product produced and other obstructions, this distance can be shorter or longer. If nodes see each other, this helps them to get better quality signals. Placement of sensor nodes in the site can be adjusted by looking at the signal link quality between nodes and parent information for each node by using the web application 18. If there is no sensor measurement flow from one node to the other, this may indicate that the nodes are not within each others coverage areas. When this is the case, the node outside coverage area of the other should be moved closer. Sensor nodes can easily be fixed to poles using, e.g., cable ties, U-bolts or clamps.

[0078] Wireless sensor nodes with integrated dry contacts (relays) can be tied to solenoid valves and climate control systems operating with electricity such as vents, fans, heating, heat curtains, shade curtains, misting, cooling pads, or alarm bell to provide control capability.

[0079] A remote wireless climate and soil monitoring and control system developed in accordance with various embodiments of the invention can have five main process flows: (a) data collection and alarm message transfer process, (b) data query process, (c) control condition dissemination and control mechanism execution process, (d) irrigation scheduling and optimization process, and (e) irrigation schedule dissemination and execution process. Detailed explanations for these processes are provided below with respect to the flow diagrams of FIGS. 3, 4, 5, 6, 8, 9, and 10.

[0080] FIG. 3 illustrates the data collection and alarm message transfer process flow. Wireless sensor nodes S1-S16 are preferably programmed before they are installed at the irrigation site. During the programming, each sensor node takes a unique serial id and each site/network is assigned a unique code. The same sensor nodes S1-S16 are also addressed with a number for easy recognition at the site. The serial numbers used are unique and all sensor nodes S1-S16 have different numbers from each other. However, addresses need only be unique within the wireless sensor network 12 for a particular site. For example, a sensor node with address “1” can exist in more than one wireless sensor network 12 (or site). In this way, during dissemination data can be sent to the right address, and during collection the source address of the incoming data can easily be identified.

[0081] After installation at the irrigation site, the sensor nodes S1-S16 discover the closest and most reliable path to the base communication node (root) 24 and form an ad-hoc (dynamic) network as shown in step (A1). Those nodes that do not have a direct communication link to the base node 24 discover routes to transfer data through other neighboring nodes. During route selection, signal quality and the number of nodes in the route are considered. Sensor nodes S1-S16 periodically (at predefined intervals) measure soil and environmental climate conditions such as soil moisture, temperature, humidity, and light as shown in step (A2). Sensor nodes S1-S16 that take measurements transfer their data to the base node 24 according to the route they discovered in step A1 at step (A3). Base communication node 24 transfers the data it collects from the network to the main server 14 through cellular network or wideband wireless network 16 at step (A4). Data transferred from base communication node 24 to the cellular connectivity terminal is stored in buffer memory to protect losses against communication failures or shortages. The main server 14 processes all the data coming from sensor networks 12 and stores them in the database at step (A5). A software program running on main server 14 compares incoming data to alarm conditions at step (A6). If an alarm situation exists, depending on the transfer medium determined at step (A7), either an e-mail at step (A8) or a short text message (SMS) at step (A9) is sent to the end user.

[0082] FIG. 4 illustrates the data query process flow in accordance with one or more embodiments of the invention. The end user can query the sensor readings from the wireless sensors in the site via cell phone 20 or Web device 18 at step (B1). For this process, end users can use their cell phones 20 to send short text messages (SMS) or to query via a client application installed on the cell phone 20 or use the web site. After receiving the query, the main server 14 processes it to understand the content at step (B2), and prepares the appropriate answer at step (B3). Depending on the query method or medium, the main server 14 decides with which of the following methods to transfer the answer in step (B4). The main server 14 can send the answer to the end user as a short text message (SMS) at step (B5). Alternately, the main server 14 can send the answer to the end user as a web page at step (B6). The main server 14 can also send the answer to the end user as a screen to be displayed on the cell phone application at step (B7).

[0083] FIG. 5 illustrates a control condition dissemination process flow in accordance with one or more embodiments of the invention. By using the dry contact outputs on main gateway device 24 or the sensor nodes S1-S16, climate control systems operated with electricity, e.g., those having motors such as misting, vents, heating, and curtains and solenoid valves can be controlled. For automatic control, various control conditions can be defined in the system. Climate control systems, solenoid valves and/or pumps are activated or deactivated as a result of comparison of control conditions against the measurements taken by the sensors local to the related device or attached to other sensor nodes S1-S16 in the network. Control conditions can be evaluated according to the following parameters:

[0084] (K1) Sensor Type (e.g., soil moisture, temperature, humidity, light): Defines against which sensor readings the control conditions will be compared.

[0085] (K2) Minimum Condition (Set) Value: Defines below what value the control will be activated (start) (K4b) or deactivated (stop) (K4a).

[0086] (K3) Maximum Condition (Set) Value: Defines above what value the control will be activated (start) (K4a) or deactivated (stop) (K4b)

[0087] (K4) Start Condition: (a) When the measurement is above the maximum condition value, the control is activated (started). When it falls below the minimum condition value, the control is deactivated (stopped). (b) When the measurement is below the minimum condition value, the control is activated (started). When it goes above the max condition value, the control is deactivated (stopped).

[0088] (K5) Work Duration: Dry contact stays active (i.e., on or working) for this duration. If zero (0), it stays active as long as the control condition is set.

[0089] (K6) Stall Duration: After working for work duration, dry contact stalls (i.e., off or not working) for stall duration. If zero (0), dry contact only works (i.e., stays active or on) for work duration (K5) and then becomes inactive even if the control condition is set.

[0090] (K7) Action Type: Defines what type of action to be taken if the control condition is set. (a) Control dry contact output; (b) Notify another sensor node.

[0091] (K8) Dry Contact No: For (K7a) case, defines which dry contact output to be controlled.

[0092] (K9) Node Address/Number to Be Notified: For (K7b) case, defines which sensor node to be notified if the control condition is set.

[0093] (K10) Synchronization Status: Indicates whether the control system will be controlled in synchronization with events and/or measurements from other sensor nodes.

[0094] (K11) Synchronization Number: If synchronization is used (K10), related sensor nodes use the common synchronization number.

[0095] (K12) Condition-in-Effect Start Time: Start time for the time interval of the day when the condition will be active.

[0096] (K13) Condition-in-Effect End Time: End time for the time interval of the day when the condition will be active.

[0097] Based on the parameters described above, the control condition is entered through the web page or cell phone 20 at step (C1) shown in FIG. 5. The main server 14 prepares these parameters to be transferred to the wireless sensor network 12 at step (C2). Prepared data is transferred from main server 14 to the main gateway device 24 through cellular network or wireless wideband network 16 and Internet 22 at step (C3). The main gateway device 24 sends control conditions to the sensor nodes through dissemination at step (C4). If the receiving nodes realize the condition is addressed for themselves, they store the condition in their internal memories and start checking them at step (C5). Related node transfers the acknowledgement (ACK) message to the main server 14 via main gateway device 24 to indicate successful reception at steps (C6, C7). If the main server 14 receives the acknowledgement message, it completes the operation. Otherwise, it assumes that the control condition has not reached to the node and retransmits it to the network 12 at step (C8).

[0098] FIG. 6 illustrates a control mechanism execution process flow in accordance with one or more embodiments of the invention.

[0099] The sensor nodes that store control conditions in their internal memory periodically take measurements to evaluate control conditions at step (D1). If a taken measurement satisfies (sets) control condition at step (D2, D3), the action to be taken is checked at step (D9). At step D3, the time of the day is also compared to the control condition-in-effect time interval (starts at K12 and ends at K13). As a result of the set control condition, if a sensor node is to be notified, a notification is sent to the related node to tell the condition is set at step (D10). If an internal dry contact output of the sensor node is to be controlled, then the related output is activated, and this way the connected control system is started at step (D11). If the control condition is not set in step D3, whether the control condition is active at that moment is checked at step (D4). If active, whether the measurement is below the min condition value or above the max condition value is checked at step (D5). At step (D5), also the time is compared to the condition-in-effect time interval. Even if the condition is not reversed, if the time is past condition-in-effect end time (K13), the flow progresses to step (D6). If (K4a) is entered in the control condition and the measurement is below min condition value or if (K4b) is selected and the measurement is above the maximum condition value, process flow goes to step at step (D6—check action to be taken). Depending on the action to be taken at step (D6), either the sensor node entered in K9 is notified at step (D7) or the dry contact output entered in K8 is deactivated/cleared at step (D8).

[0100] FIG. 8 illustrates the irrigation scheduling and optimization process flow in accordance with one or more embodiments of the invention.

[0101] At step (E1), the server calculates/projects the irrigation schedule for the season or the growth period based on ET values of last year's weather information (historical data—on-site or nearby weather stations) for the site and site specific information such as crop type and soil mixture and the growth period (e.g., blooming, pre-harvesting etc.). For example, the water balance approach can be used for scheduling the irrigation. When the schedule is first created or any time it is adjusted, it is optimized for a given watering window (e.g. water may only be available during certain times of the day and/or certain days of the week). The server optimizes/adjusts the irrigation schedule for a given period of time based on a past period of time at step (E2). In this example, the irrigation schedule is adjusted for the next 7 days based on last 7 days' ET calculations on a daily basis. (This duration could be different time periods, e.g., 3 days or 5 weeks etc.)

[0102] Then, server checks if the soil moisture measurement optimization is enabled (E3). If it is enabled (E4), the server optimizes the remaining irrigation schedule based on soil moisture sensor readings. If the difference between actual soil moisture readings and the predicted soil moisture levels based on the ET calculations is greater than a predefined threshold number, the server modifies the schedule to match the actual soil moisture readings.

[0103] If the soil moisture optimization is not turned on, the server checks if the actual flow data optimization enabled at step (E5). If it is enabled, the server optimizes the irrigation schedule for the next 7 days based on actual irrigation data on the past 7 day period at step (E6). In this way, any irrigation deficiency is addressed from the previous time period (e.g., 7 days).

[0104] At step (E7), server checks if weather forecast optimization is enabled. If it is enabled, at step (E8), the server looks at the public or private weather forecast data and decides if the schedule should be modified (e.g., delayed) for a given rain amount and probability by comparing the thresholds defined by the user. After the scheduling and optimization is complete, the server sends next 7 days' schedule to the control nodes at the site on a daily basis at step (E9). This process goes back to (E1) if the end of season or the growth period is reached (E10) or back to (E2).

[0105] The wireless sensor nodes have the capability to control solenoid valves or pumps. They can be connected (wired or wirelessly) to battery or electricity operated valves to turn them on and off. In this way, the controlling capability is distributed in the network without wires (no wires for communication and no wires for electricity as the nodes are battery operated). Thus in some embodiments, there is no need for a central controller to control operation of valves and pumps.

[0106] FIG. 9 is a flowchart illustrating an irrigation schedule dissemination process in accordance with one or more embodiments of the invention.

[0107] At step (F1), an irrigation schedule is generated/adjusted by the server as illustrated in FIG. 8. The schedule for the following time period (e.g., 7 days) is sent to the network through main gateway on a daily basis (or other appropriate frequency) at step (F2). The main gateway disseminates the schedule in the network at step (F3). The related wireless control node receives and stores the schedule, e.g., in an internal flash memory at step (F4). At steps (F5 and F6), the node acknowledges (ACK) the server about receiving and storing the schedule through main gateway. At step (F7), if the server doesn't receive the ACK, the process goes back to step (F2) to resend the schedule. Once the schedule is successfully stored in the node, the server sends periodical updates on the schedule to the node at step (F8).

[0108] FIG. 10 is a flowchart illustrating the irrigation scheduling execution process in accordance with one or more embodiments of the invention.

[0109] At step (G1) the control node checks its local time and compares it to the schedule condition and decides when to turn the valve on or off. If it is time to turn on a closed valve (G2), it turns on that particular valve at step (G4) and notifies the server about that event through main gateway at step (G6). If it is time to turn off an open valve (G3), it turns off that particular valve at step (G5) and notifies the server about that event through main gateway at step (G6).

[0110] It is to be understood that although the invention has been described above in terms of particular embodiments, the foregoing embodiments are provided as illustrative only, and do not limit or define the scope of the invention. Various other embodiments, including but not limited to the following, are also within the scope of the claims. For example, elements and components described herein may be further divided into additional components or joined together to form fewer components for performing the same functions.

[0111] Method claims set forth below having steps that are numbered or designated by letters should not be considered to be necessarily limited to the particular order in which the steps are recited.