Communications satellites use steerable antenna arrays for their communication links. These arrays need multi channel signal routing circuits up to several tens of channels. Traditionally this circuitry has been realized with hybrid technology. This has resulted to tens of Watts in power consumption and several kilograms of payload weight. In this paper we describe monolithic integrated switch and vector modulator matrixes for signal routing and beamforming, operating in the 160 MHz IF range. These 12 - 16 I/O channel LSI level analogue circuits reduce power consumption of the satellite beamforming circuitry to a few watts and weight to less than one kilogram. The power consumption per matrix node is 10 - 20 mW compared to the 100 - 500 mW consumption in the hybrid solutions.