Research On A New Method Of On-board FDMA-TDM Conversion

On-board Processing(OBP) is an important direction in satellite communications, where on-board conversion from FDMA to TDM is very useful in raising channel efficiency and decreasing cost of earth stations. Basing on extensive research of the FDMA桾DM conversion, this thesis proposes a new way for such conversion, i.e. FDMA桟WTDM conversion, which is based on a China invention patent ?A Time Division Multiplexing Transmission Technique for Band-Limited Signals . Comparing with the FDMA桾DM converter, the FDMA桟WTDM converter has much lower power cost and complexity. Around this new scheme, the author has done some research as follows:1.The author researches, in depth, on some key techniques such as Continuous Wave Time Division Multiplex (CWTDM), Multi-Carrier Demodulation (MCD) and frequency division de-multiplexing, and has some of them applied to the FDMA-CWTDM conversion.2.A demonstration of a satellite communication system based on an on-board FDMA桟WTDM conversion transponder is implemented in a development platform of Borland C++ Builder 5. The demonstration shows that the on-board converter works well, where the BER of the receiver equals to 0 even when some AWGN noise exists in the channel.3.The author has found a suitable tool used for system-level simulation ?Elanix SystemView, and developed some key modules to construct a SystemView simulation for the FDMA桟WTDM conversion system, which would be very helpful for its hardware implementation.