Wireless gateway can use specific protocols to communicate with IoT devices, and then store, parse, and calculate the data, and send it to the cloud server for processing and analysis. Since different IoT devices use different types of wireless or wired technologies to transmit data, wireless gateway act as checkpoints, gates, and bridges in various communication protocols and networks and becomes a tool for communication protocol and interface conversion.
Benefits of Wireless Gateways
Wireless gateway mainly routes data packets from a wireless LAN network to another wired or wireless WAN. It enjoys the benefits of wireless network, including:
- Easy installation: reducing the workload of network wiring;
- Flexibility: within the signal coverage area of the wireless network, the IoT device can access the network at any locations, and the wireless network can penetrate walls, so it will not be blocked by buildings;
- Easy Maintenance: if there is a problem with the wireless network, you don’t need to mess around to find out which wire is the problem. Generally, you only need to solve the problem of the wireless gateway.
With the continuous development and improvement of wireless network technology, the prospect of wireless gateway is undoubtedly very good.
IEEE802.15.4 is a physical layer and MAC layer protocol developed by IEEE802.15 Group for low-power wireless personal area network. This protocol stack operates on license-exempt frequency bands such as 868 to 868.6MHz in Europe, 902 to 928MHz in the US, and 2400 to 2483.5MHz in the rest of the world.
IEEE802.15.4 was developed for short-range communication between low-power devices. This data communication is characterized by low data rates, limited bandwidth, and low transmission power. Because Most IoT devices and transceivers are battery powered, IEEE802.15.4 allows these devices to last for extended periods without battery replacement.
In IEEE802.15.4 standard, IoT devices can be connected in a star topology or a peer-to-peer topology. When multi-hop routing must be used to extend network coverage, peer-to-peer topology are often preferred. To achieve multi-hop routing over longer distances, IoT devices must work together due to the limited transmission range of peer-to-peer topology. Therefore, the packet size is limited to 127 bytes and the communication rate is limited to 250kbps.
The encoding scheme in IEEE802.15.4 has built-in redundancy, which makes the communication robust, allowing detecting data loss and retransmissing lost packets. It also supports short 16-bit link addresses to reduce header size, communication overhead, and memory requirements.
The IEEE802.15.4 standard is the basis for many other LAN and PAN protocol stacks, as well as Zigbee, WirelessHART, Thread and MiWi.
ZigBee is a protocol stack based on the IEEE802.15.4 standard, originally developed for industrial use. It mainly operates in the 2.4GHZ frequency range with a data rate up to 256Kbps.
There can be up to 65536 nodes in a ZigBee network, and the total network coverage is limited between 100 and 200 meters.
Data communication can be carried out between any nodes in the network. The network has an automatic repair function when modules join and withdraw.
Explore more on ZigBee in IoT and Zigbee Gateway
Thread is an IPv6-based network layer protocol that uses the IEEE802.15.4 standard at the physical layer and MAC layer. It was developed by ThreadGroup for Home Automation Network (HAN).
Thread is based on IEEE802.15.4, IPv6 and 6LoWPAN standards, and operates at a frequency of 2.4GHz at the physical layer (PHY). There can be up to 250 nodes in the Thread network, and data is secured by implementing various authentication and encryption techniques.
The operating frequency range of Z-Wave is 800-900 MHz, and Z-Wave supports data transmission of 9.6-10 kbps.
Each Z-Wave network has its own independent network address, and the address of each node in the network is assigned by the control node. Each network can accommodate up to 232 nodes, including the control node. There can be multiple control nodes, but there is only one main control node, that is, all nodes in the network is distributed by the main control node, and other control nodes only forward the commands of the main control node.
Common nodes that have joined the network can be controlled by all control nodes. Nodes beyond the communication distance can be controlled by routing through other nodes between the controller and the controlled node.
Explore Z-Wave Gateway
EnOcean (Energy Harvesting Wireless Technology) is a wireless protocol stack that operates on 868 MHz in Europe and 315 MHz in the US. It is a physical layer and MAC layer protocol with a network coverage of 30 meters indoors and 300 meters in open areas.
EnOcean is very streamlined and uses a communication mechanism that does not require handshaking. The standard covers the first three layers of the EnOcean network architecture: the physical layer, the data link layer and the network layer, and the fourth layer is formulated by the EnOcean Open Alliance.
EnOcean is an ultra-low-power short-range wireless communication technology based on energy harvesting, which is applied to indoor energy harvesting. The standard has been developed for networking battery-free wireless sensors in a personal area network (PAN).
Modules based on EnOcean technology have the characteristics of high-quality wireless communication, energy harvesting and conversion, and ultra-low power consumption. EnOcean can provide energy for the module by collecting tiny energy from nature, making the module battery-free and maintenance-free.
Explore EnOcean Gateway
Wi-SUN is a standard LPWAN network protocol based on IP technology. It uses the global standard IEEE 802.15.4G as the basis to unify the technical specifications of the physical layer, link layer, network layer and transport layer. Meanwhile, Wi-SUN ensures interoperability among certified products by unified consistency certification.
All IoT terminal devices embedded Wi-SUN protocol, such as smart meters in AMI, smart street lights in smart cities, can make wireless communication and reduce industrial operation and maintenance investment, by connecting to a public Wi-SUN network, which is comparable to Wi-Fi technology.
Cellular offers reliable broadband communication and get popular in consumer mobile market, but it also features high operation costs and power consumption, thus not suitable for battery-operated sensor networks. Cellular IoT applications primarily use these two technologies: LTE-M or NB-IoT.
LTE-M, stands for “Long Term Evolution for Machines”, and is a networking standard that allows IoT devices to piggyback on existing cellular networks. Generally speaking, LTE-M devices are best suited for some critical important applications that require high real-time data transmission, such as self-driving cars or emergency equipment in smart cities.
Explore More on Long Term evolution LTE and Cellular LTE gateway
NB-IoT means Narrow Band Internet of Things. It is very suitable for applications in areas without good LTE coverage, or IoT project applications that only need to transmit a small amount of information, such as the application of soil sensors in smart agriculture, or energy usage monitoring sensors in smart cities, and more. NB-IoT uses only a fraction of the total bandwidth base station resources. Therefore, NB-IoT is more suitable if the required project only needs to send a small amount of data over the Internet on a regular basis.
Bluetooth and BLE
BLE is short for Bluetooth Low Energy. Bluetooth low energy technology is a low-cost, short-range, interoperable and robust wireless technology that operates in the license-free 2.4GHz radio frequency band. BLE characteristics are:
- Low cost and power consumption
- Quick start and instant connection
- The transmission distance can be increased to 1km (explore more on Bluetooth long range)
- AES-128 encryption algorithm for data packet encryption authentication
BLE occupies an increasingly important position in the field of short-distance wireless communication, and wireless Bluetooth gateways are also appearing in more and more IoT applications:
Remote patient monitoring device: pulse oximeter, blood pressure cuff, continuous glucose monitors and so on;
Smart home gadgets: Bluetooth mesh lighting control, temp&humidity sensor control, smart lock control and so on;
Indoor location hardware: Bluetooth beacons.
The LoRaWAN protocol is based on the LoRa radio modulation method and is a low-power wide-area network protocol. It manages communication between end-node IoT devices and network gateways, and connects devices to the Internet.
Advantages of LoRaWAN Network Include:
Long Range and Coverage: Its range of up to 15 km within LOS and this is unmatched by any other communication protocol;
Low Power Consumption: LoRa technology provides ultra-low power radios, ideal for devices that will last a decade or more on a single charge;
Low-cost Hardware: The cost of LoRaWAN infrastructure is very low compared to other networks, as is the radio cost of end devices.
High Capacity: A single LoRa gateway can potentially connect thousands of endpoint IoT devices.
Explore More on LoraWAN Gateway
Sub-GHz refers to the radio frequency band with a frequency below one gigahertz. These frequency bands are characterized by long transmission distance and strong penetration ability, but narrow bandwidth. The sub-GHz band has less spectrum interference than the 2.4GHz band. So what? Frequency bands with less interference can improve the overall performance of the network and reduce the number of retransmissions in transmission.
Sub-GHz is ideal for long-distance and low-power communication, and its applications cover consumer electronics, automotive, industrial and medical, etc., and use cases include TV/STB/VCR/DVD/Audio equipment remote control, high-end toys, garage door opener, lighting control, door opener, wireless health monitor, wearable monitoring device, etc.
Explore More on Sub-GHz Gateway
Which IoT Wireless Technology is the Best for Your IoT Gateway?
There is no one-size-fit-all choice. Which one should you choose is highly depending on your own needs. So what should be considered for trade-offs?
What customers always cares most about is operation time, data transfer length, and power consumption. These coincide with things need to be paid attention on wireless transmission: the power required to transmit, the data rate, and transmission range. Here we give some tips for you when you want to choose a wireless technology solution for your IoT gateway development. Also, we welcome you to ask for a proposal to out IoT experts.
Things you need to consider include:
- Data rate
- Transmission distance
- Licensed vs. unlicensed spectrum
- Carrier vs. customer deployed
- End device density
- Deployment location
- Firmware updates
- Operation system Drivers
- Module selection (explore our System on Modules here)
- Technology Maturity