C-Band Frequency and Wavelength Minimize Rain Fade

Although radio waves can penetrate solid objects, they tend to slow down and fade if their path is thousands of miles long. Things get worse when there is a rain or snow. Rain can decrease mobile broadband connection. The ideal locations for satellite uplink or downlink points are areas with the least atmospheric disturbances.

Satellite communications carriers can offer three bands – Ku, Ka and C bands – depending on meteorological factors. Each of the three bands has different thoroughput and speed due to varying wavelengths and frequencies. We can find the lowest frequency in the C band, while the highest frequency is seen at the Ka band, which boasts of the shortest wavelength as well. The lower the frequency, the greater is the radio band’s resistance against signal attenuation due to rainfall (rain fade). C band thus emerged as the best option for satellite broadband communications in places where it rains frequently.

No universal C-band frequency standard has been agreed upon, but the frequency range of C band is between 3.7 and 7 GHz. For the K bands, frequency ranges are 26.5- 40 GHz for Ka and 12-18 GHz for Ku band.

For many years, C band is the preferred broadband channel for satellite TV transmission. Many modern wireless communications systems also support C band. Low-frequency radio waves provide online connectivity to wireless telephones, Wi-Fi gadgets and even radars.

Weather disturbances turn the atmosphere into a rough road for radio waves. Fortunately, C band has low frequency and longer wavelengths, so it can easily penetrate rainfall. In tropical towns and communities, satellite broadband via C band allows people and businesses to make VOIP calls and increase bandwidth capacity instantly. C-band customers in Asia-Pacific regions can now enjoy stable broadband connection, contact emergency response groups and access telemedical services in any season of the year, rain or shine.

Due to rain fade, C band technology is likely to remain popular. Rainfall affects choices related to teleport location, type of satellite dish and type of radio band to use. A marginal change in the speed of satellite signals can dramatically ruin online experience and flow of real-time communications. Customers connecting online via K bands are more likely to encounter higher error rates, substandard thoroughput and even significant downtime during rainy season.

The normal ceiling for rain fade is 1 GHz. Electromagnetic waves beyond this level are vulnerable to rain fade. Sometimes, rain fade affects even areas that are not experiencing weather disturbances. It is because signals may encounter electromagnetic interference on their way to satellites or transceivers.Signals from satellite dishes positioned in a low look angle are more likely to experience such a problem.

Due to the climate in tropical regions, C band remains the most used radio band there.
Satellite dishes for Ka and Ku bands can be modified to make them fit for C band connection, but it is still more cost-effective to use the large satellite dishes built especially for C band.

Market analysts expect C band to remain the dominant satellite technology for satellite TV operators. Despite Ku and Ka bands’ higher thoroughput, they cannot offer the same rain-fade protection as C band waves do. Satellite TV broadcasting requires higher limit on minimum speed, unlike online video streaming in which signal latency can be tolerated more by viewers.

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