Firstly, a DDS-based method for digital-domain synthesis of time-varying Doppler frequency in dynamic GPS signal is proposed in this dissertation.

论文首先基于直接数字频率合成技术提出了一种能够在数字域内直接合成出动态信号中时变多普勒频率的信号合成方法。

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The exact synthesis equation of motion in frequency domain and frequency-response functions for structural vibration were obtained according to the Ritz procedure.

然后根据里兹法，得到结构精确综合的频域运动方程与频响函数；

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