Link Budget Calculations for K/Ka-band Satellite Mobile Communication Systems

To calculate the required RF power for the transmitters for a mobile satellite link, radar equations are utilized. In this work, the requirements of K/Ka receiver/transmitter antenna arrays for modern communication system which consists of two separate antennas are achieved to create scanning radiation patterns for transmitter and receiver for a 5G/6G system for VSAT applications. Having analyzed the link budget, it is shown that the antenna systems have to include 64×64 arrays which prepare at least 35dB array gain and the total transmitted RF power must be more than about 603W (60.3W in clear sky). For a typical TX/RX 5G/6G system, specifications can be: TX frequency: 19GHz up to 21GHz; RX frequency: 27GHz up to 31GHz; SWR: <3; three dimensional scanning angles: -60° ≤ θ ≤ 60°, φ=360°. In this work, the frequencies are selected based on wider bandwidths and the lowest atmospheric gasses' attenuations for a 5G/6G communication system.