Phased array antenna with a modular system for improved servicing access

A phased array antenna 100, satellite system or method of servicing a phased array antenna comprises a horn/filter assembly 105 attached to an RF module 140 where the module is mounted on a first surface 138A of a thermal system 130 and a distribution board 150 is mounted on a second surface 138B. An interconnection 160 is arranged to extend though the thermal system 130 and electrically connect the distribution board 150 to the RF module 140. The modular system allows the horn/filter assembly 105 and the RF module 140 to be disassembled for servicing without disrupting the distribution system 150 or the thermal system 130. The horn/filter assembly 105 may be circular or square in cross section and screwed or clipped into engagement with the RF module 140. The thermal system 130 may include plural heat pipes 132 sandwiched between flanges 138 or heat spreading plates on to which RF modules 140 and distribution boards 150 may be screw mounted. The modules 140 or the distribution boards 150 may include parts which extend through the thermal system 130 such that simple short interconnections 160 are required between them. The distribution boards 150 may be multi-layer circuit board arrangements for RF and DC signals.