When it comes to creating a smart space, the large number of devices spread across a wide area combined with the need for all these devices to transmit data makes communication a major area of concern. While there are many different communication technologies available, choosing the right one can be a difficult task, as each communication technology has its own pros and cons.
Furthermore, a design that picks a communication method that is not suitable for its application will not only suffer from design flaws but may even require a new design from the ground up, as the underlying hardware originally chosen may not be compatible with another communications technology.
As such, it is essential for engineers to take the time to figure out exactly what the requirements of their project are, what each communication technology can offer, and which one is the most appropriate for their situation.
What factors matter when choosing a smart space connectivity option?
When choosing connectivity technology, a multitude of different factors can make or break a solution. In the case of smart spaces, these will most likely come down to range, power, bandwidth, reliability, features, and security.
Selecting a connectivity option based on range will enable devices to operate at greater distances, but this may come at the cost of power consumption. Range is directly related to power consumed, and thus, technologies with the greatest range will consume the most power (unless they sacrifice their bandwidth).
Power is the second-biggest factor to consider when implementing a wireless solution, as power consumption widely varies across different technologies. Technologies with lower bandwidths and lower ranges will often consume orders-of-magnitude less energy than high-power, long-range technologies, and this may be desirable for devices powered by batteries with limited amounts of immediate power.
Bandwidth is another important factor to consider, as some devices may be required to stream large amounts of information (such as cameras), while others may be able to get away with sending a few bytes each hour. It is best to try and use the lowest bandwidth possible, as this will often allow for greater ranges while also reducing power consumption significantly.
Reliability is a factor that can be problematic for designs needing to provide real-time responses. This does not mean that data is always being sent, but it does mean that the moment an event is triggered, either the device or service it connects to must be able to respond immediately. A wireless communication technology that cannot provide reliability may miss events, leading to an unreliable system.
While all wireless communication technologies provide data transmission as a fundamental service, some technologies can provide additional features, such as positioning. Such features may be able to add additional functionality at no extra cost to a design.
But of all factors listed above, one of the most important by far is security. With the increasing importance of privacy and security in modern electronics, future smart spaces will be dominated with internet-enabled devices, and the potential for private data to be gathered (faces, biometrics, etc.,) will see a need for devices in smart spaces to be secure. As such, any wireless communication technology chosen would need to be secured against attacks.
What are the major smart space technologies?
While several wireless technologies exist, the most common ones are Wi-Fi, Bluetooth, cellular, and ultra-wideband (UWB). Other technologies such as LoRaWAN and satellites do exist, but they are used in more specialist applications in which sensors may be found in extremely remote areas.
Wi-Fi is an excellent technology for applications looking for good range and high data rates. As Wi-Fi has been developed with consumer electronics in mind, it is designed for use with gaming, video streaming, and file sharing — all of which can be extremely demanding. However, the low latency, high bandwidth, and long range comes at the cost of high-power usage, which can make Wi-Fi a poor choice for devices powered by batteries.
Bluetooth is a wireless technology that operates on the same frequency spectrum as Wi-Fi (2.4 GHz), but unlike Wi-Fi, it has a range of only a few meters and significantly lower data rates. This results in Bluetooth being an extremely low-energy option (compared with Wi-Fi), and the development of Bluetooth Low Energy is an even better addition for applications looking to operate on battery for extended periods of time. However, the reduced bandwidth means that sensors looking to transmit large data packets may do better with a different technology.
Cellular communications (such as 4G and 5G), use less energy compared with Wi-Fi and offer excellent range and bandwidth. This technology also takes advantage of the fact that an area with mobile coverage does not need to install any special equipment for sensors to connect to the network. However, cellular coverage is not always great, and remote areas can especially suffer from network access.
UWB is a network technology that has recently started to gain traction thanks to its ability to provide long-range communication while using significantly less energy than Wi-Fi and cellular. Furthermore, the use of a wide spectrum and short bursts of energy allow for extremely accurate positioning of devices. Thus, UWB is particularly advantageous in applications requiring asset tracking in motion.
Which smart space connectivity option is best?
After reviewing the various connectivity options available to engineers, the question remains: Which one is best? The answer is none of them, as the choice of which connectivity technology to use all depends on the requirements of the design.
Outdoor smart spaces in urban areas can highly benefit from cellular networks thanks to the wide coverage provided, the ability for devices to be installed in most locations while still receiving a reliable signal, and the suitability to work with battery power. Furthermore, the use of cellular networks removes the need for additional routers, bridges, or modems that sit between devices and an ISP, which significantly reduces the complexity of hardware.
Indoor smart spaces (such as homes) can take advantage of Wi-Fi due to its good range, wide availability to private individuals, ability to provide low-latency messages, and widespread use in pre-existing IoT devices. While Wi-Fi is energy-demanding, devices installed inside would likely have access to mains power.
Smart spaces that do not have power infrastructure may be reliant on batteries, and in such cases, either Bluetooth or UWB can be beneficial. Some low-energy Bluetooth devices already exist on the market that power themselves through mechanical force (such as a doorbell), which demonstrates just how little power is needed to run Bluetooth devices.
Applications that involve moving sensors (such as pallet trucks, people, or packages), can take advantage of UWB, which offers long range, low energy, and accurate tracking. UWB is already in use with asset-tracking devices such as Apple AirTags, and more smartphones are now seeing UWB integrated into their designs.
Where will the smart space industry head?
Of all the communication technologies currently in use, cellular is looking more like the ultimate solution for smart spaces. First, smart spaces of the future will most likely be confined to cities, industrial sites, and homes, and all these places have cellular reception. This means that devices can be added to a smart space without the need to install new networking equipment, and the only requirement for adding new devices would be to point them to the correct cloud service.
While 5G is still being rolled out, 6G is already in development, and it has even been claimed to be the first unified network whereby 6G would be the only wireless network needed. Of course, Bluetooth and Wi-Fi would still play a role, but a centralized network could bring major advantages such as better coverage and simpler installation. Furthermore, smart spaces are likely to contain hundreds of sensors, and current Wi-Fi networks are not designed to handle this many connected devices at once (while cellular networks are).
Many connection technologies exist and choosing the right one for your application is essential, as trying to make changes to a design too far into the development stage can be extremely costly. When deciding on a technology, outline what the primary requirements are for your design, and then consider what future features you may choose to include. Finally, think about where the industry may be headed, as making devices compatible with future solutions could provide a massive competitive advantage over devices that need to be replaced.