Making the most of sub 3 GHz licensed bands

The frequency spectrum is a natural resource that needs to be used rationally and efficiently for maximum benefit.

The Aprisa XE uses only licensed frequency bands, protecting your link and eliminating the commonplace interference issues experienced by links operating in unlicensed bands. It operates in the fixed service bands of the lower microwave spectrum below 3 GHz. This spectrum range offers impressive long haul capabilities, and these bands have been used for this distance advantage since microwave links were invented.

Making best use of such suitable spectrum means using the most efficient modulation methods and other technologies to promote best frequency re-use. The Aprisa XE has been designed from the ground up for this environment, with maximum performance. From South American railways to mining concerns in the tough Australian outback, the Aprisa XE is the long haul technology of choice.

As well as achieving longer links, we also make the most of the other inherent advantages offered by frequency bands below 3 GHz, where the longer wavelengths of these bands experience less free space loss. The Aprisa XE exploits these benefits to ensure that it remains unaffected by the environmental conditions that cause problems in the higher frequency bands, such as rain and dust storms.

As an example of the impact of a rain storm, attenuation of the receive signal is caused by rain drops absorbing or scattering radio frequency energy. This is noticeable on an increasing scale above 4 GHz. Compare a 40 km path in the 7 GHz and 2 GHz bands. In the 7 GHz band, there could be up to 30 dB of rain fade, leading to the link being lost. At 2 GHz, using the Aprisa XE, there would only be a 0.5 dB loss in the same conditions, and the link would still have five 9s availability.

In a similar way, the haze-like effect resulting from dust and stand storms such as Harmattan and Khamsin can be catastrophic for higher frequency links, but links below 3 GHz experience only a negligible signal fade, maintaining their availability.

For unbeatable performance, the Aprisa XE, using sub 3 GHz licensed bands, wins every time.