Efficient M-QAM Transmission Using Compacted Magnitude Modulation Tables

Magnitude Modulation is a technique proposed with success for QPSK and OQPSK in order to maximize power and bandwidth of small satellite earth stations, by reducing PAPR of the modulated signal at the HPA input. To meet the ever growing demand for higher data rates, higher order modulations have been considered. This paper shows that it is possible to use the magnitude modulation concept for the M-QAM case, even considering the huge number of symbol combinations. The constellation and RRC symmetries are explored, allowing considerable reduction on look-up table computation complexity and storage requirements. Experimental results show considerable gains (>2dB) in PAPR and back-off reduction for 16-QAM with negligible BER losses.