What do civil engineers love, but electrical engineers hate? Concrete. This thing that makes up the base of our physical world often confounds the electrical signals that are the foundation of our digital world. Parking decks, malls, and underground structures all suffer from bad signal coverage. Without some kind of window or repeater, you’ll rarely get good coverage in these areas. That’s becoming a problem as the Internet of Things (IoT) is expanding into those kinds of places. That’s where low power wide area networks (LPWAN) come in. LPWANs can help solve coverage and power problems for IoT devices. In addition, they can open up low power and distributed service options that will revolutionize the IoT.
The name pretty much says it all. LPWANs are supposed to provide network coverage over a wide area to low power devices. To be clear, LPWAN is not a standard but is simply a description. There are, and have been, a variety of companies that provide LPWANs using several different technologies. The only requirements for these systems are that they cover a “wide area” (usually more than 2 km) and enable low power devices. If they want market penetration, they need to do this at a low price.
The wide area is needed to enable dispersed configurations like utility monitoring for a large complex or building. The decentralized nature of LPWAN systems means purchasing lots of sensors and devices. Those costs add up, so in order to succeed a LPWAN also needs to have a low price point. Most sensors and devices on LPWANs will need to operate for years (10 seems to be the standard) on batteries. That means sensors will be low power, and the LPWAN must use a low power networking solution. The only drawback to low power networks is that they reduce data rates. As a result, most LPWANs are suitable for applications with low throughput.
The LPWAN market is growing at a tremendous rate and expects to connect 4 billion devices by 2025. This rising tide is driving intense competition, extending even into the telecommunications industry.
Cell networks are not currently considered LPWANs. However, that may be changing as cell carriers try to enter the market. Telecoms already have vast infrastructure that can enable them to easily implement networks. Another cell advantage is that the companies’ business models allow them to sell LPWAN systems for cheap. They make their money on contracts, not on hardware. That model incentivises them to sell as many systems as possible for a low price. Like I said earlier, the less expensive the better when it comes to LPWANs. The low power requirement is the only one that carriers are having trouble with. Current cellular antennas draw too much power to be useful for many LPWAN applications. That too, though, is changing, as telecoms are investing in developing low power solutions.
What does this mean for LPWAN companies operating in the unlicensed frequency bands? Well, they will soon be joined by carriers with extensive stakes in the licensed domains.
So what do LPWANs have to do with the IoT? Individual IoT devices are already growing in number, and the IoT will soon grow in scale. The next step in the IoT is “smart” systems. These systems would move from manually controlled discrete devices to networks of automatically managed items.
There are several systems that can benefit from current LPWAN capabilities. These include things like utility monitoring systems, self-parking systems, and object tracking. Most of these places will be indoors with lots of concrete to attenuate signals, hence the near for wide area coverage. They also need lots of low power sensors that can send small packets of data to each other or to a centralized controller. Without LPWAN you’d be stuck sticking WiFi routers into every crevice and cranny of a mall, just to connect an ambient temperature sensor. Power would be another big problem. Imagine having to connect every one of your parking spot sensors to the grid. No thanks.
Existing LPWAN technology can handle these applications, and is already doing so. One example of the utility of LPWAN is in city lighting. Disbursed sensing with centralized control can allow the lights to dim or raise to appropriate levels based on location. This can save cities money, though to be honest, the margins aren’t high. The greater benefit is for tracking and maintenance. With an LPWAN maintenance teams can know exactly where and when a light has gone out. This is where LPWAN can really help, by making distributed systems easy to monitor and control.
The main inhibiting factor for LPWANs is their bandwidth. Low power requirements mean low transmission rates. So things like water meter data can be sent over the network, but not pictures or video. The next generation of LPWANs will still meet the wide area, low power, needs while also providing greater bandwidth.
One of the biggest applications for high bandwidth LPWANs will be autonomous vehicles. More and more cars are using advanced driver assistance systems (ADAS), and several companies are pushing further towards fully self-driving cars. These cars will become driving IoT hubs and will need to connect to a network to function. Currently, 4G is the only network they can use, but it’s not ideal. Autonomous vehicles will need a lower power network solution as their processors become more power hungry. That’s where 5G comes in. 5G will give cars higher bandwidth connections for lower power usage than 4G. A 5G LPWAN will allow cars to download and upload huge amounts of data, increasing the safety and comfort of their drivers.
A far-reaching internet of things has been slow in coming, but it’s almost here. LPWANs will soon be widely adopted to connect large, concrete filled facilities and make them “smart.” Keep your eye on the market as cell companies battle with unlicensed spectrum startups for pieces of the LPWAN pie. Current solutions can enable “smart” parking, metering, and lighting systems with low bandwidth needs. As time marches on we’ll see higher data rates in LPWANs, which will be used to connect self-driving cars. Now it’s up to you to design PCBs for all of these systems.
Have you ever tried mixing concrete by hand? It’s a long, tedious, and strenuous process. Things are much easier when you use the right tools, like a concrete mixer. The same goes for designing PCBs for LPWAN systems. Your PCBs will need to be small, robust, and low power to work with most LPWAN applications. CircuitStudio® is the tool that will make design easy for you. With a wide range of advanced features, will help you design like never before.
Have more questions about LPWANs for the IoT? Call an expert at Altium.