Wireless Sensor Networks
- [Wireless Sensor Networks - GeeksforGeeks]
- Overview
In recent years, the efficient design of wireless sensor networks (WSNs) has become a frontier area of research. A sensor is a device that responds to and detects some type of input from physical or environmental conditions, such as pressure, heat, light, etc.
The output of the sensor is usually an electrical signal, which is transmitted to the controller for further processing. This article provides an overview of the types, classifications, attack types, mobility and routing protocols of wireless sensor networks.
WSNs can be used in many industries, such as agriculture, food and beverage, and environment protection. They can help maintain optimal environmental conditions, which can improve safety and quality.
Please refer to Wikipedia: Wireless Senor Network for more details.
- Components of A WSN
WSNs are self-configuring networks that use radio signals to communicate between sensor nodes. A sensor node, also known as a mote, can act as a data originator or router.
Sensor nodes are used in WSNs along with onboard processors to manage and monitor the environment in a specific area. They are connected to base stations that act as processing units in WSN systems.
Base stations in the WSN system are connected through the Internet to share data.
Here are some components of a WSN:
- Radio nodes: These components have a microcontroller for data processing, a transceiver for wireless communication, external memory for data storage, and a power source.
- WLAN access point: This component receives data wirelessly from radio nodes and acts as a gateway for sensor data to be transmitted to remote locations.
- Network Topologies of WSNs
A wireless sensor network (WSN) is a network of sensors that monitor and record environmental conditions. WSNs are made up of sensors, routers, gateways, and machines that use two-way radio transmissions to collect, store, and collate data.
WSNs can measure physical conditions like: Humidity, Temperature, Sound, Pollution levels, Wind, Vibration, Motion.
WSNs can have different topologies, including:
- Point to point network
- Star network
- Tree network
- Mesh network
- Sensor Networks and Wireless Sensor Networks
A sensor network is a group of sensors that monitor data and send it to a central location for analysis, viewing, and storage. Sensor networks can connect to computer networks or the internet to transfer data for analysis and use.
- Area monitoring: A common application of wireless sensor networks (WSNs). For example, a military might use sensors to detect enemy intrusion, or a civilian might use them to geo-fence oil or gas pipelines.
- Wild fire tracking
- Animal observation
- Agriculture management
- Industrial monitoring
WSNs are wireless networks that use many wireless sensors in a large number of situations. They can be deployed on land, underground, or underwater. Sensor nodes have three subsystems: Sensor subsystem, Processing subsystem, Communication subsystem.
WSNs have five layers based on the OSI model: Application layer, Transport layer, Network layer, Data Link layer, Physical layer.
- Wireless Sensor Networks Platforms
Wireless Sensor Networks (WSNs) are spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperature, sound, pressure, etc. and to cooperatively pass their data through the network to a main location. The more modern networks are bi-directional, also enabling control of sensor activity.
The development of WSNs was motivated by military applications such as battlefield surveillance; today such networks are used in many industrial and consumer applications, such as industrial process monitoring and control, machine health monitoring, and so on.
The WSN is built of "nodes" – from a few to several hundreds or even thousands, where each node is connected to one (or sometimes several) sensors. Each such sensor network node has typically several parts: a radio transceiver with an internal antenna or connection to an external antenna, a microcontroller, an electronic circuit for interfacing with the sensors and an energy source, usually a battery or an embedded form of energy harvesting.
A sensor node might vary in size from that of a shoebox down to the size of a grain of dust, although functioning "motes" of genuine microscopic dimensions have yet to be created.
The cost of sensor nodes is similarly variable, ranging from a few to hundreds of dollars, depending on the complexity of the individual sensor nodes.
Size and cost constraints on sensor nodes result in corresponding constraints on resources such as energy, memory, computational speed and communications bandwidth.
The topology of the WSNs can vary from a simple star network to an advanced multi-hop wireless mesh network. The propagation technique between the hops of the network can be routing or flooding.
- The IoTs and Wireless Sensor Networks
A Wireless Sensor Network (WSN) is a key component of the Internet of Things (IoT). WSNs are used to connect devices and systems, and are a key part of IoT. WSNs are used for data collection and monitoring, while IoT is used for a variety of purposes, including data collection, monitoring, control, and communication.
Here are some advantages of WSNs:
- Low cost: WSNs are made up of small, low-cost sensors.
- Wireless communication: WSNs don't have wired connections, which makes installation easier and reduces costs.
- Portability: WSNs are portable and easy to implement.
- Interconnectedness: WSNs allow for seamless communication and data sharing.
- Real-time applications: WSNs are one of the best techniques for many real-time applications.
WSNs use a private network of sensor nodes, routers, gateways, and authorized machines to collect, collate, and store data. Their main function is to process extracted data and transmit it to remote locations.
- Energy harvesting-based WSNs (EHWSNs)
Energy harvesting-based WSNs (EHWSNs) are a type of WSN that can extract energy from the surrounding environment. Energy harvesting can exploit different sources of energy, such as: Wind, Solar power, Mechanical vibrations, Temperature variations, Magnetic fields.
Energy harvesting-based WSNs (EHWSNs) are wireless sensor networks that can extract energy from their environment. The harvested energy is converted to electrical energy and stored in a storage device to power the sensor nodes.
- Self-powered Sensors
Self-powered sensors are designed to harvest energy from their environment. They can draw power from vibrations, temperature gradients, or radio waves.
Here are some examples of self-powered sensors:
- Pressure sensors: Designed for standard hydraulic environments where pressure fluctuations are present
- Motion sensors: Can monitor the motion parameters of moving objects
- TENG-based sensors: Can detect wind speed, rainfall intensity, humidity, and more in the environment
- EnOcean-based products: Perform without batteries and are engineered to operate maintenance-free
Self-powered sensors are designed to be designed for energy harvesting, which includes the sensor, data processing, and communication part.
[More to come ...]
