Analysis of Modern Digital Modulation Techniques.
Joseph L Craddock · Defense Technical Information Center (DTIC) · 1978
Offset Quadriphase Shift Keyed (OQPSK) modulation, Minimum Shift Keyed (MSK) modulation and Sinusoidal Frequency Shift Keyed (SFSK) modulation are analyzed and compared within this report. First, OQPSK, MSK and SFSK are examined both graphically and mathematically, and compared to the fundamental modulation techniques of FSK, PSK and QPSK. Second, a common mathematical framework unifying the three modulation techniques is developed. Third, the theoretical spectral properties of each are calculated. The spectral properties include the autocorrelation function, power spectral density, spectral occupancy, spectral shape and roll off characteristics. Next, the practical spectral properties of the three modulation techniques are developed using a realistic bandlimited, nonlinear channel. Finally, simulated and measured performance of OQPSK and MSK are given and compared using probability of error as the figure of merit. (Author)