↑ The Rebirth of Shortwave Radio Communication

By Doron Tal, 4X4XM

Short radio waves, often referred to as high-frequency (HF) radio waves, have played a crucial role in global communication and are integral to various applications.

Since the late 1960s, satellites have replaced shortwave for global communications for several reasons. Satellite communication does not involve frequent changes in the quality of communication conditions. They allow much higher bandwidth. Satellite communication enables more reliable communication that does not require daily operation by skilled or experienced operators.

However this trend has changed. High Frequency (HF) radio is regaining popularity for long-distance communication due to its durability and independence from infrastructure, making it indispensable during emergencies.

The ionosphere's ability to reflect shortwaves enables long-distance communication.

Long distance communication by ionospheric refractions

The monitoring of ionospheric conditions is currently done using automatic devices:

Remote sensing of ionospheric layers
Typical ionosonde

Such devices assist to prepare map of estimated propagation conditions.

A review of the last 24 hours HF Propagation Map:
MUF 3000 Km map animated review of HF propagation map
Static maps provided by Andrew D Rodland, KC2G updated every 15 minutes.
The animated version was made by Roland Gafner, HB9VQQ who extended
the static presentation, showing the last 24 hours, in 15 minutes steps.

Researchers and radio operators continuously monitor ionospheric conditions to predict and adapt to changing propagation characteristics, ensuring the reliability of short radio wave communication in diverse scenarios, from emergency response to global broadcasting.

HF technology provides global coverage without requiring special infrastructure, saving satellite shielding costs. Recent developments enhance dependability, although they are not as fast as satellite data transfers. The HF domain is good for digital voice communication and text messaging systems.

Learn more about Short Radio Waves Propagation. See also an index for Propagation of high frequency radio waves.


The Understanding HF Propagation Project provides radio amateurs with a detailed overview and tutorials on several aspects of HF propagation.

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