‘Digital Audio Broadcasting’ is the modern advancement over the old analog FM radio service.
Digital Broadcasts
You need a digital radio to receive digital audio broadcasts because FM analog radios are not backward compatible. While potentially offering the same service, digital radio, and FM radio services are transmitted using two very different systems.
FM Built-in
While the Android headunits have built-in FM capability, the Digital Radio option is usually left as an extra option. The analog AM and FM radio chips are very cheap when built into an Android headunit, and the AM/FM is a worldwide standard. This makes AM/FM an ideal standard feature for androids.
Adding Digital Radio
The expansion for digital radio reception will often be found in a simple USB stick device with a connection for an aerial. A limited number of countries with a DAB digital radio service makes this an excellent cost-saving choice. There is no advantage to adding DAB chips and their additional cost that will never be used.
Some countries with digital radio services do not support DAB or DAB+, so an alternative, compatible digital radio adaptor will be required. The adaptor must be chosen to match the system currently in use. Notably, DVB-T2-Lite is employed in some areas of the world as a digital radio standard and is incompatible with DAB/DAB+ hardware.
Digital Radio Popularity
The worldwide take-up of digital broadcast radio has been poor compared to that of the incumbent FM system. There seemed to be a slight advantage to digital radio, considering the need to buy a new radio to support the new technology. However, the increasing popularity of internet streaming radio made DAB broadcast digital radio less appealing.
Future Digital Radio?
The ideal digital radio for the home could be an internet radio. These can be cheap to produce and have a built-in Wi-Fi dongle to connect to the home router. There is a massive pool of internet radio stations with no interference from vehicles passing, and they connect to the existing Wi-Fi network at home. We are almost there with the Amazon Echo device.
When it works
Digital Radio has its problems. The radio transmission needs to make its way to the digital radio aerial with little degradation to the signal. If there are obstructions or interference, digital radio signals can affect the radio’s sound. The digital radio’s poor signal is disturbing some listeners with chirping and squeaking sounds, making the listening experience unpleasant. While FM analog radio can also be affected by interference and obstructions to the signal, the effect is less dramatic, and as the signal fades, so does the volume.
Digital Radio Aerials
Digital radio benefits from a dedicated aerial for its frequency band, which is much higher than the old FM analog service. This makes the old FM aerial not an ideal partner for a new digital radio installation. Adding a new digital radio-compatible aerial to the vehicle’s roof will give the receiver a much better digital radio signal, leading to a better sound output.
Why Digital Radio?
Digital Radio is much more efficient in using the radio spectrum for broadcast services. Only so many frequencies are available, and there needs to be ‘space’ between the allocated frequencies to avoid interference between the different stations. DAB and digital radio can fit more radio stations into the same frequency band as FM. Because each station takes less space and all the stations can be more tightly packed into the frequency band available without interference from each other.
A larger number of radio services in the same frequency allocation can mean more consumer choices and more revenue for the authorities collecting broadcasting license fees.
Why not stream?
Streaming music over the Internet is very popular. You don’t need any extra hardware to decode the signal; you need an internet connection. DAB digital radio may be available in areas with poor mobile coverage as this does not need mobile phone coverage. But in most cities, there is plenty of 4G or even 5G now, so streaming with an app is often the choice for in-car digital radio and the Android headunit.
