Shortly before access to the BBC News site would have been blocked in Russia a few days ago, the The BBC announced that it was taking over broadcasting of the BBC World Service via shortwave radio for four hours a day. He said this was to ensure that people in parts of Russia and Ukraine can access his news service.
In a world where mobile phone adoption is nearly ubiquitous, the use of early 20th century radio technology may seem unusual. But it makes sense for a number of practical reasons.
Shortwave radio is an older variation of what many people may remember as analog “AM” radio, operating on low frequency radio waves to provide audio services. Shortwave radio is much simpler than modern digital television or telecommunications services: receivers are widely available (or can be built from spare electrical parts), and it works over long distances.
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Traditional television and radio are fundamentally different from modern Internet services. Like Freeview TV received over an antenna, traditional broadcast radio services don’t require you to transmit anything in order to receive a service. It is transmitted once, and anyone with a receiver can listen or watch.
When someone uses a shortwave radio receiver, there is no lasting record of its use. It is therefore difficult for an occupying force to find those who listen to (perhaps banned) foreign media.
Conversely, when you browse the Internet or use a mobile application, your device requests the content you want to receive and it is sent directly to your phone. This two-way communication means that when you browse the internet, various entities like your internet service provider can see that you have visited some websites.
Internet services can also be overloaded, either due to high demand or due to malicious attacks. flood a service with requests, aiming to make it unavailable.
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There are a number of other technical reasons why shortwave radio can be very useful in crisis situations. As it uses lower transmission frequencies, signals can travel much farther than TV or mobile phone signals – thousands of kilometersrather than kilometers or tens of kilometers.
This means that the BBC can broadcast from outside into a conflict zone without the need for local physical infrastructure. And since low frequencies are used, the signals spread better through buildings and the environment. If you’ve ever encountered a poor cell phone signal in the center of an old building, you’ve encountered the challenges of radio propagation. Low-frequency signals reach buildings and basements better, even when transmitted from afar, which could be useful for people taking shelter.
Shortwave radio receivers can also be very energy efficient. You can run a portable radio for days on batteries, and many cars come with a shortwave-capable radio that can run off the car battery. There are even hand-cranked or solar-powered shortwave radio receivers. available.
Although cell phones can be charged from power banks, solar panels, or car chargers, they require a lot of infrastructure, such as radio masts, power connections, and fiber networks. One of them could fail, or be deliberately targeted, removing all or part of the network. If your local mast loses power, the network will drop into this area. If core network sites are damaged or lose power, the entire network will become unavailable.
Additionally, cell phones and other digital radio technologies are designed to use low transmit power to make it more cost effective for mobile operators to reuse the same frequencies in different domains. This means that network operators reduce signal strength wherever possible.
This makes it convenient for almost anyone to try block and block access to mobile networks, using portable jamming devices (which are generally illegal own or use). Shortwave signals are more difficult to block, usually requiring a network large, high-power transmitters spread across a country, operating on the same frequency.
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In today’s warfare, the shift to traditional radio communications technology is not only observed in the context of news broadcasts. There are numerous reports of Russian military units using unencrypted analog radiosor “walkie-talkies”, to communicate on the battlefield.
In hostile environments, sometimes older and simpler technologies are more readily available and can provide a more reliable communication channel than more complex modern alternatives.