The Digital sub-band system is an indispensable technology for the development of modern society, which has a wide range of applications. This work is particularly concerned with developing applications for modulation techniques used in mobile communication. Based on MATLAB, this paper compared the modulation and demodulation of 2ASK, 2FSK, 2PSK, and QPSK horizontally and analysed the practical and theoretical error rates. With the constellation maps of 16QAM, 32QAM, 64QAM, and 256QAM, the relationship between the error rate and the signal-to-noise ratio was studied. In binary modulation systems, 2PSK has the best noise resistance and requires 6dB less SNR than 2ASK when employing the same demodulation approach. In addition, this paper outlined the technologies and modulation standards employed in the development of 1G-4G. To make the comparison clearer, the advantage, disadvantages, and modulation comparisons among 1G-5G are displayed. The analysis and research of digital sub-band modulation technology is the basis for developing new technology in the future.

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