DSP处理器在复杂低频信号合成中的应用

Application of DSP processor in synthesis of complex low frequency signal

为解决甚高频全向信标/仪表着陆系统标准信号源中复杂信号的合成问题,提出了采用数字信号处理器(DSP)进行信号合成的原理。该原理是以DSP处理器为基础,采用数字式直接频率合成器(DDS)的技术方法,利用DSP处理器内部丰富的硬件资源,在DSP内部构建DDS的框架电路,并利用DSP内部各单元灵活的可编程特性,实现了信号的合成。信号合成过程中充分发挥了DSP、DDS的技术优势,同时实现了信号的调幅、调频,高精度相位、幅度预置等功能。最后通过高精度D/A转换器实现了信号的模拟输出。以电路实际输出的合成信号的波形图与实测结果的形式,验证了所讲述原理的正确性。

To resolve complicated signal synthesis in signal resource design for very high frequency omni direction beacon/instrument landing system, signal synthesis principle with digital signal processor （DSP） is proposed. The principle is that on base ofDSP, DDS frame circuit is built inside DSP with of digital direct frequency synthesizer and inside abundant hardware resource, and flexible progra- mmable characteristics of DSP units is used, signal synthesis is realized finally. In process of signal synthesis, technique advantages of DDS and DSP are exerted and amplitude modulation and frequency modulation, functions of precise phase and amplitude presetting are realized at the same time. Analog signal is outputted with high precision D/A converter at last. The paper provides the real synthesis signal waveform and measured result from the circuit to validate the principle correctness.