Some practical considerations for depolarisation compensation in 14/11 and 14/12 GHz communications satellite systems

Dual-polarisation frequency reuse in communications satellite systems at 14/11 GHz imposes stringent isolation and attenuation margin requirements. Many satellite links will be depolarisation-limited. In most cases, a phase-only depolarisation compensation network will restore adequate isolation in the 14/11 and 14/12 GHz bands. However, orientation of the linear polarisation vector to be close to horizontal or vertical at the earth station eliminates the need for depolar isation compensation in nearly every system. This technique is illustrated for an INTELSAT V satellite in the Atlantic Ocean region.