If you want car WiFi, or car internet, as those terms have become completely interchangeable now, let us show you how we achieved this. Sure, some modern cars come with this feature but ours didn’t, and as we will explain, we wanted to minimise the compromises.
We spend a lot of time in our car both for work and pleasure, and we wanted to establish a more solid connection to the internet when in the car. Yes, using your phone as a hotspot is an option, but it was not the most convenient as we would need to open the setting to allow devices to connect. When it was on it drained the batter, and performance was a bit average, both speed and coverage.
Whatever you do, but especially when working with radio communications, there is an element of compromise. An example is that if you want the best coverage, you need antennas mounted as high as possible. Think mobile phone masts, or antennas on the top of a building. So, pursuit of the best coverage, will make the car less practical. The opposite of this is that not impacting the cars practicality at all will reduce the level of coverage. A smartphone is a perfect is example of this. Gone are the days of external antennas on mobile phones, coverage is compromised to benefit aesthetics and portability.
We wanted to find our own balance of compromise to get the best car WiFi possible whilst not looking like the lunar rover.
We based the system around a Huawei 4g router. but we selected a model that could have external antennas connected. This is important because cars are a faraday cage which really means that radio signals don’t like passing in or out. To maximise performance, we needed to get an aerial to a spot that would give the best reception.
Outside the car on the roof would be best, but this doesn’t always look great and unless willing to drill a hole in the roof, would mean running lots of cable around to get the aerial outside. Compromise alert… the longer the cable, the more signal you lose. This means putting an antenna 100m in the air using standard cable would mean the signal would have mostly leaked out by the time you got it to the other end. Unless using special cable which is hugely thick and impractical.
We wanted a better option. Technically a car’s windows offer a way in and out of the faraday cage, but not the front window as these have a special UV coating to help prevent the car heating up too much on a sunny day. However, there is small area around the rear view mirror, which is coloured slightly differently, and does not have the UV coating. It is actually designed for antenna placement and lets radio signals pass as well a possible.
We opted for a MIMO antenna on the front windscreen to give the best balance of performance and practicality. MIMO is a technology that uses 2 antennas mounted in a specific way to collect more signal resulting in better reception.
This was run neat inside trim panels to the glove box where the router was positioned.
Power was taken for the USB from a suitable circuit that turned on when the ignition was on. This would charge the battery in the router and allow it to run whilst the car was parked.
We configured the router to auto power down if there wasn’t nothing connected to preserve the batter.
Choosing a SIM was an interesting point, and we have found it far better to buy a preloaded data SIM that suits our needs. We stated with a 1 month option and stepped it up to 3 months, and once we knew roughly how much data we used, we bought a 12 month SIM preloaded with 120GB. We are now on our second one of these.
We could not ask for better performance. The wireless is there whenever we need it. The children can use it on a long drive, and we even have Wi-Fi calling on our phones, which offers a backup for when the signal gets poor on the phone, which seems to be everywhere. As the data SIM is from a different operator, coverage black spots are reduced. Even bits of road we were guaranteed to get cut off are a thing of the past!
