Dual Chirps Direction Shift Keying Modulation

Although chirp spread spectrum (CSS) modulation in the LoRa system offers remarkable receiver sensitivity, its data rate is rather limited. Aiming at data rate enhancement, this letter presents a novel modulation scheme called Dual Chirps Direction Shift Keying (DCDSK). The DCDSK employs dual up-chirp or dual down-chirp superposition transmissions to enhance the data rate and introduces a Discrete Fourier Transform (DFT) spectral kurtosis-based non-coherent demodulation algorithm to lower the bit error rate (BER). Moreover, the theoretical BER performance of DCDSK is analysed. The simulation results validate the superiority of the DCDSK modulation over existing CSS-based modulations in terms of both the data rate and the power efficiency.