HF radio: Back to the future!

The following article is from Mira, OM3CKU: Free according to the company materials CRYPTO AG and Racal.

High frequency electromagnetic waves (KV) takes over 1,5 – 30 MHz from the frequency spectrum. After the discovery of radiotelegraphy at the end of the 19th century, they dominated wireless communication for decades. But what is the value of KV in the Internet age? Today's technical solution suggests: KV is capable of development and compatible with the Internet.

In the time of information technology boom,it seemed almost as if KV was gradually becoming an obsolete technique compared to VHF, microwave and satellite connections, optical networks and interconnection of networks seemed to be a suitable technology for almost all services. Although, these seemingly quite fast, new communication technologies also created new possibilities, but they certainly cannot offer the best price solution for all applicable variants. After all, it is important to have other alternatives available for the operational connection of self-government during an emergency. And this is exactly where KV demonstrates its strengths. But it's not quite that simple “put everything back”, KV also has the advantages of digital processing and can take over some important functions in building communication systems of all sizes.

KV: Qualities that never get old.
Every means of communication has physical limitations and shortcomings should be respected, but also used. Respecting them, KV offers very well-known parameters: KV can create a separate and secure wireless connection over any distance, including an international connection. KV is kind of “free agent” for aviation, including crisis situations or disasters.

The physical dependence on factors such as season and time of day and the amount of solar activity is now easily managed with frequency selection that can be automated. Other steps, the operational quality requirements have long-term trials behind them. Big advantage: KV can be used by both stationary and mobile stations.

In technical terms: KV has really benefited greatly from the development of integrated circuits. The signaling process is now predominantly digital and correspondence reliable. And what more, an extremely extensive set of knowledge and experience gives many possibilities of used variants. Therefore, we can assume that KV applications will play an important role in the future.

Large range of location.
A wide range of possibilities for using KV exists not only for voice communication, but also for data communication in “stable” a “movable” modes, including “portable” examples of use:

• Use stable:

Diplomatic radio networks, independent of foreign operating centers, a means of remote connection, as well as backup for government and military use, connections with ocean-going ships (both civilian and military), emergency networks.

• Mobile/portable applications:

Diplomats on the move (governs, organizations), mobile networks for police and security services, large nets for border guards (lode, aircraft and vehicles connect with each other and with operations centers at virtually any distance), systems for mobile and portable equipment in all types of troops.

Renaissance thanks to the integration system.
Here are other reasons for the KV renaissance. It is true that in many cases the opinion still prevails, that KV is mainly suitable for voice transmissions. In fact, it has a long tradition of use for data communications. Modern wireless systems use modems or automatic switches for optimal speed/bandwidth selection. Channel selection and other parameter settings can also be partially automated, operator input is now usually very small.

Also integration into extensive connection and data networks (with an Internet connection) can be implemented. If the participant uses the information system, can be communicated via radio link, in moving or stable mode, with the Internet or WAN/LAN participants and use the entire chain of services.

This is how we perceive existing KV systems, but with the aim of increasing their reach and also integrating them into mass networks. Principle: “when nothing else, KV still works”, it always has a justification and will be used in the future.

High security!
The intensity of KV technologies and their safety was recognized very early (before the Second World War) and practical solutions were developed only during it. Numerical technology makes it possible to keep up with technological progress.

With the transition to VHF/UHF bands, the security aspect was neglected for a long time, especially with regard to the Internet. Assumption, that such connections are less susceptible to attack has proven to be a fundamental fallacy.

KV doesn't need to get all the way here. It is a rule, that KV users traditionally have a very high level of security awareness, which is not yet common in other technologies! We feel this is a very positive point of view when it is necessary to compile safety measures for the entire systems that make up the operating stage.

High security relies on cryptology.
Highly secure KV- the transmission is carried out by encrypting the signals entering the radio systems. Voice transmission is possible in analog or digital mode. Digital data transfer in synchronous or asynchronous mode is at a speed dependent on the bandwidth. Robust Pactor II mod (more robust than the new Pactor III) is continuously used. Appendix STANAG 5066 and NATO data links, they also count on him.

Finally, security can be implemented by encrypting the signal by the user using a PC or laptop and used immediately (or through a data server) as the radio signal arrives. This even works with hand-held combat-ready laptops. In voice transmission, the encryption unit is connected between the microphone and the transmitter. For large systems with multiple levels, multi-channel encryption and radio units can be built-in simplex, half-duplex or duplex device. KV allows to ensure, wide transmission system, processing and storing information and thus a very reliable link in the information and data chain. Only secret really, special customer algorithms and security systems can use hardware and software at the same time in order to ensure high security applied to all KV systems. Thanks to this philosophy, compressed keying is not a risk. For example: Password-protected device access depending on usage, security models are also mechanically protected and automatically destroy all stored data in the event of an attack on the device. If direction is to be secured during transmission, then this can be handled safely with hopping or spread spectrum. These methods are mainly used in military and naval applications.

The strategic point of leadership can be largely automated, requiring nothing but a manual push of the distribution button (drawn from the card or via the keyboard)no further action. Use of Security Network Management (SNMC) and a network distribution button (encoded) is a common technology standard today. Compatibility issues with currently available KV systems do not usually cause problems if they are equipped with suitable interfaces with the necessary parameters.