How does in-car WiFi work?

In-car WiFi is the latest attempt at bridging the connectivity gap between our homes and our vehicles, promising seamless entertainment and communications

Thursday, 17 November, 2022

In future decades, youngsters will marvel at how complicated and piecemeal the 2020s telecommunications infrastructure was.

They’ll wonder why we didn’t have seamless connectivity wherever we went, instead of the current patchwork quilt of WiFi and hardwired broadband, public networks and cellular 4G/5G data.

They’ll be astonished that we had to physically plug smartphones into our cars to achieve even partial device mirroring on infotainment screens, or that home internet access wasn’t portable.

They’ll regard these gaps in the same way we now think of cassette mix tapes, or two-band radio – anachronisms of a technologically limited age.

In-car WiFi is specifically designed to bridge the digital divide between our homes and our vehicles.

But how does it work? And is it much help in real-world use?

Pretty fly for a WiFi

We live in an age of WiFi on planes, so its incorporation into passenger vehicles comes as no surprise.

Some manufacturers build WiFi hotspot capabilities into their vehicles. To use BMW as an example, new models have a SIM card integrated into their infotainment systems.

A number of manufacturers fit omnidirectional antennae and amplifiers to boost data signals, maintaining connectivity in rural areas such as deserted stretches of motorway.

You’ll have to connect mobile devices through the car’s touchscreen to access this connectivity, which forms an alternative to conventional mobile data contracts.

To prevent drivers being distracted, smartphone mirroring is a limited version of the phone’s full capabilities. Key apps will be accessible, but you may not be able to text, for instance.

If your car doesn’t have WiFi already engineered into it, off-the-shelf solutions represent an alternative.

You could tether a web-enabled device to share connectivity with other tablets or laptops in the vehicle.

You could even invest in a mobile MiFi dongle. These typically take their power from the car’s cigarette lighter (the 12V port, for our younger readers), though some are battery-powered.

Both these solutions are relatively expensive, as data is often charged by the gigabyte, and activities like mobile gaming can be hugely data hungry.

It should go without saying – though we’ll say it anyway – that such systems are only meant for passengers to use. Drivers must always remain focused on the road.

Why is in-car WiFi likely to be short-lived?

Switching devices between home broadband, mobile 4G/5G and in-car WiFi through a dedicated SIM card or dongle is clearly an unsatisfactory state of affairs.

We wrote last month about the likelihood of a fully operational 5G network being able to provide seamless connectivity to devices, irrespective of where they are.

We’re still some way from that, and home broadband will remain essential for many years to come, while Ofcom releases 5G network bandwidth and hardware evolves to exploit it.

Until then, in-car WiFi offers an intermediate step along the road to seamless device connectivity at all times, and in all locations.

Neil Cumins author picture


Neil is our resident tech expert. He's written guides on loads of broadband head-scratchers and is determined to solve all your technology problems!