E-band

E-band refers to the portion of the radio-frequency spectrum from approximately 71-86 GHz. It is commonly associated with very high-capacity millimeter-wave links and is often divided into two main ranges, 71-76 GHz and 81-86 GHz. In satellite communications, E-band is of interest for high-capacity feeder links, inter-satellite links, and future broadband satellite architectures requiring very wide bandwidths.

The main advantage of E-band is the availability of large contiguous bandwidths. This makes it attractive for systems that need to move very large quantities of data between gateways and satellites, or between satellites in space. The short wavelength allows antennas to produce very narrow beams from relatively small apertures. Narrow beams can improve frequency reuse and reduce interference, but they also require accurate pointing, stable platforms, and careful tracking.

E-band links are strongly affected by propagation impairments on Earth-space paths. Rain attenuation can be severe, and clouds, atmospheric gases, scintillation, and water vapor can also contribute to link degradation. These effects make E-band less suitable for simple low-margin links and more suitable for carefully engineered applications. Fade mitigation techniques such as adaptive coding and modulation, uplink power control, gateway diversity, site diversity, and traffic rerouting are commonly associated with E-band satellite designs.

E-band is already important in terrestrial fixed wireless backhaul, where short high-capacity links can be engineered with narrow beams. In satellite communications, its use is more specialized and is generally associated with future high-throughput systems rather than conventional wide-area user access. The band offers great capacity potential, but this comes with demanding requirements for radio-frequency hardware, antenna pointing, atmospheric modeling, regulatory coordination, and operational availability.