A METHOD FOR GENERATING A BUILT SYMBOL FOR DATA TRANSMISSION AND A METHOD FOR DEMODULATING A RECEIVED BUILT SYMBOL

摘要

The invention concerns a method for generating a built symbol comprising a plurality of sub-symbols for transmission comprising data of an original symbol of an orthogonal multi-carrier modulation signal in order to reduce the peak-to-average power ratio (PAPR) and increase its robustness against Doppler effects of the orthogonal multi-carrier modulation signal, the original symbol lasting for a duration Ts and carried by N tones; the method comprising: by applying the intrinsic temporal diversity properties of the complex N-points Inverse Fast Fourier Transform to the original symbol, wherein the number of the generated plurality of sub-symbols is M, each of the M generated sub-symbols lasts for a duration Ts/M and is carried by N/M disjoint tones, and the M generated sub-symbols are time-multiplexed, so that the time-multiplexed built symbol contains all the data at the same rate of the original symbol. The built symbol can be demodulated by utilizing an orthogonal multi-carrier receiver. The invention also concerns a demodulation method configured for demodulating the received built symbol comprising the M sub-symbol by demodulating sequentially sub-symbol by sub-symbol, which significantly improves the robustness of the signal against Doppler effects. The invention comprises further a step of increasing the secrecy at the physical-layer of the communication system by taking all the advantages of the unique properties applied to generate the time-multiplexed built symbol for transmission.