A flexible digital multicarrier modulator for multi-frequency TDMA satellite transmission

The implementation and test of a flexible digital multi-frequency time division multiple access (MF-TDMA) modulator are presented. The modulator is able to work at several frequencies (frequency hopping) on a burst basis without preambles or guardtimes. After a brief review of some satellite concepts (e.g., MF-TDMA, onboard processor, and traffic efficiency), direct-in-band modulation is introduced as the technique selected for the digital design of this frequency hopping modulator. A mixed Si/GaAs technology has been chosen for the hardware implementation and some tests are presented to show the good performance of the device.<
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