The present invention relates to a system for transmitting data in the form of at least one sequence of pulses modulated by symbol encoding means. According to the invention, the symbol encoding means include a plurality of signal encoders ENCi connected to a plurality of antennas ANTi and comprising each: pulse generating means PGi for delivering a basic pulse sequence PSQi, energy splitting means ENSPi for splitting said basic pulse sequence into sub-sequences Psqi1 . . . PsqiK, signal modulating means SGM1 . . . SGMK for applying to each sub-sequence a tunable coefficient, and combination means CMBMi for combining all sub-sequences Tsgi1 . . . TsgiK into a signal Tsgi to be transmitted by the antenna ANTi to which the encoder ENCi is connected. Thanks to the invention, each signal encoder ENCi is linked to a single antenna ANTi, which enables to ensure that said antenna will have essentially constant physical properties within its own frequential range of operation.