Two weeks ago, I have been approached with the following situation: "On the one hand, I use Bluetooth to connect my phone to my car as well as my smart watch to my phone. On the other hand, I connect my computer via WiFi to my router and from there into the Internet. So, Bluetooth seems more for mobile things, but WiFi seems the option for all the Internet stuff. So, would you recommend Bluetooth or WiFi to transfer data wirelessly on a construction machine or a jobsite in general?" My short answer was: "It depends!"

For a more specific answer, let’s look into some specifics about the two different wireless technologies.

Let’s start with range. Bluetooth has an intended range from less than 10 m (33 ft) up to 100 m (328 ft). In the WiFi world, there are no pre-defined ranges. Here it depends on aspects like transmission power and antennas. To complicate matters, a lot of countries have specific regulations around maximal antenna power output. However, the current distance record is held by the Swedish Space Agency with 420 km (260 miles) – using special equipment. But even with common technology, our Moba MCA 3000 system uses WiFi to connect the different rollers up to 200 m (656 ft).

Another aspect is bandwidth. For Bluetooth the maximum bandwidth is 24Mbit/s. Whereas WiFi allows up to 862Mbit/s with its newest standard.

Related to range and bandwidth is power consumption. It is easily imaginable that WiFi needs to create a stronger signal (and therefore consuming more power) as WiFi signals need to travel further and with higher bandwidth. Rahul Balani from the University of California at Los Angeles has shown that in worst case scenarios Bluetooth needs less than 3% of the power WiFi would need for the same task.

Other very interesting and sometimes overlooked aspects are the multiplexing and routing capabilities of the different technologies. Multiplexing means the capability to send information to multiple (up to all) receivers at once. With routing it is possible to send data between different networks. In fact, routing makes your access to the Internet at home actually work. Your requested for a website (like mobacommunity.com) is routed from your home network to your provider’s network, from there to Moba’s provider network and from there to the actual server (and obviously back). So, WiFi supports routing. Even though there still some issues around multiplexing for WiFi, it is supported in general. Bluetooth usually does not support multiplexing or routing. The most common use case is a so-called point-to-point connection (like your phone and car are connected).

Lastly, I want to mention the aspect of set-up and ease of use. Even though the people who struggled with a Bluetooth pairing lately, might disagree, but – in general – Bluetooth is easier to set-up. WiFi now has possibilities like WPS, which reduce set-up hassles, however it can get somewhat more complicated.

So, coming back to the opening question, whether I would recommend Bluetooth or WiFi for construction machines and jobsites. I hope I showed you that it depends on what you want to achieve.

For example, if you have a lot of production data, which need to be shared between machines as fast as possible and also send to the Internet, then I would opt for WiFi. However, if you have a battery powered device, which needs to be in the field as long as possible and you can live with lower bandwidth, the natural choice would be Bluetooth. Actually, you might end up needing and using both wireless technologies.

What do you think? Did I miss aspects which are important for you?