DRM Can Complement Countries Already Served by DAB+, Avoiding Reliance on a Single Short-Range System

DAB+ is a system designed for short-range coverage, with an average transmission radius of about 60 km. Of course, this can vary depending on topography, transmitter power, and the characteristics of the antenna system, either increasing or decreasing depending on the scenario. However, a country served exclusively by DAB+ would require an extremely dense network of transmitters and repeaters, which would only be economically viable in small countries.

A Complementary Role

DRM, on the other hand, presents itself as a complete system precisely because it offers two complementary branches: DRM+, ideal for metropolitan coverage, and DRM in AM, which provides both extended reach and solid performance in urban areas. It’s worth noting that although both systems use OFDM technology, they were developed with different technical focuses and have distinct solutions for reception, modulation, and error correction.

DAB+ is not a system I see as having real potential for implementation in Brazil, as its format diverges significantly from the country’s existing broadcast infrastructure. Even systems more aligned with the current philosophy already face adoption challenges. In Natal, for example, I don’t see DAB+ testing as feasible in the short or even medium term.

However, in countries where DAB+ is already in operation—but still rely on analog transmissions to reach small towns and underserved highways—it is necessary to consider complementary solutions. In such scenarios, DRM can play a strategic role, extending coverage and promoting true digital inclusion in radio.

Risks of Relying Solely on a Short-Range System

Although DAB+ offers excellent audio quality and modern features, its short-to-medium range requires a high density of transmitters to ensure nationwide coverage. While this works well in medium to large cities, it becomes costly, inefficient, or even unfeasible in rural, remote, or low-density regions.

Relying solely on DAB+ carries structural risks:

• Inequality in access to information between rural areas and major urban centers.

• High infrastructure costs, making digitalization economically unviable in distant regions.

• Disruption of traditional broadcasting, without a viable digital alternative where AM or FM would be shut down.

• Information blackouts during emergencies, weakening radio's role as a resilient and trusted medium.

Why DRM Is the Ideal Complement

In this context, DRM emerges as an ideal complementary solution:

• It covers long distances with fewer transmitters, including the use of medium and shortwave bands.

• It leverages existing AM infrastructure, reducing investment costs.

• It reaches areas where DAB+ would never be economically viable.

• It also operates in the VHF band (DRM+), enabling hybrid network integration.

A Smart National Strategy

Combining DAB+ and DRM would allow for:

• Balanced and efficient coverage, with DAB+ serving metropolitan areas and DRM covering the rest.

• Both standards can coexist in the same receiver.

• Efficient use of spectrum and existing infrastructure, enabling a more sustainable digital transition.

Opting for a single short-range system may seem simpler, but it does not solve the challenge of universal coverage. For digital radio to fulfill its democratic role, it must be inclusive, accessible, and strategically planned. The integration of DAB+ and DRM is likely the only technically and economically viable path for truly nationwide digital radio.

What About Digital FM?

In Brazil, a successful DRM rollout in the AM band could also serve as an educational tool, helping the public and the market understand the real benefits of digital broadcasting, both in terms of quality and functionality.

This would create a positive perception environment, encouraging industry, commerce, and new business models built on innovative features like interactive services, dynamic text, metadata, emergency alerts, electronic program guides (EPG), and even file delivery.

The debate over FM digitization would also come into focus if a positive AM experience were successfully implemented, reducing resistance and gaining supporters even among broadcasters.

Stronger Protection in Urban Areas

Both DAB+ and DRM+ were designed with specific protections against multipath interference, one of the main challenges to radio signals in large urban environments.

If you experience signal drops in your favorite FM station while in the city, it’s likely due to signal reflections off buildings, causing destructive interference. In analog systems, this results in static, distortion, or volume fluctuations. In digital systems, it causes dropouts, but modern digital technologies include advanced mechanisms to correct or minimize these effects.

The Risk of Geographical Limitation

Urban-only transmission creates coverage gaps outside major cities. This doesn’t only affect small communities—travelers, truck drivers, and peri-urban residents may also lose access. Systems with strong geographic limitations hinder national integration.

With DRM in AM and shortwave, it's possible to establish nationwide coverage using a small number of transmitters, upholding the right to universal access to information and reinforcing the strategic role of radio in national development.