High Power GaN Based Ku-Band SSPA Systems

By L. Mateev, Senior RF Design Engineer and C. Damian, VP Product Line Management and Business Development, Advantech Wireless Inc.

Taking in account the latest achievements in the digital signals processing, encoding techniques, IP based communications systems, new modulation and FEC techniques – the Satellite communications systems today are moving from Multi-carrier Transponder usage to a Single high Data rate carrier per Transponder. All services sharing the common carrier (TV channels, Radio channels, VoIP services, Data channels and so on, are multiplexed into a common high data rate stream which is transferred trough the communications channel and separated at receive site based on their packet identifiers in real time. The main advantage of this approach is the Single carrier Transponder usage which allows using of the Satellite Transponders close to their saturation point (instead of 4-5dB output Back-off in Multicarrier mode) – this way of using them allows much smaller Receive Antenna dishes (40 – 80cm in Ku band systems), improved system margins and Link availability figures, better Quality of all services.