Due to the higher frequencies of this band, it can be more vulnerable to signal quality problems caused by rain fade, again ACM is used to help rain fade. Transmission power is much greater compared to the C, X or Ku band beams. Ka band dishes can be much smaller and typically range from 60cm-1.2m (2′ to 4′) in diameter. The Ka band (K band Above) is primarily used for two-way consumer broadband and military networks. Networks in this band are more susceptible to rain fade, especially in tropical areas and ACM is used to prevent these outages. The antenna sizes, ranging from 0.9m -1.8m (~6ft), are much smaller than C band because the higher frequency means that higher gain can be achieved with small antenna sizes than C-band. Ku (K band Under) band is used typically for consumer direct-to-home access, distance learning applications, retail and enterprise connectivity. This band is less susceptible to rain fade than the Ku Band due to the lower frequency range, resulting in a higher performance level under adverse weather conditions. With relatively few satellites in orbit in this band, there is a wider separation between adjacent satellites, making it ideal for Comms-on-the Move (COTM) applications. The uplink frequency is higher than that of the down because the transmit amplifier in the down link has a limited power supply power budget as it is on. The X band is used mainly for military communications and Wideband Global SATCOM (WGS) systems. However, due to the lower frequency range, it performs better under adverse weather conditions on the ground. Because of its weaker power it requires a larger antenna, usually above 1.8m (6ft). The C band is primarily used for voice and data communications as well as backhauling. These different frequency bands have separate uplink (Tx) and downlink (Rx) frequencies, require different RF components ( LNB and BUC) and are suited to different applications. Satellite VSAT communication is split up in to four Radio Frequency (RF) bands that commercial communication and military satellites operate within.
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