Design Of Data Processing And Signal Source For Testing In Dynamic Signal Analyzer

Dynamic Signal Analyzer(DSA) is an all-purpose FFT analyzer with built-in signal source. It has the advantages of large dynamic range, high accuracy and selectable spectrum analysis bandwidth. Traditional dynamic testing and analyzing equipment is often a complex system consists of sensors, conditioning circuits, sampler and signal source with a complicated operating procedure. The rapid development of microelectronics technology brings out a DSA combining signal acquisition, storage, analysis all in one. This thesis accomplished a design of data process and the built-in signal source hardware architecture FPGA + DSP based, the main contents are:Data pre-process of DSA: Studying the method of data sampling and analysis under multiple instrument modes, we designed the pre-process logic of test data, it mainly contains the logic of trigger module, ddc module and multiple sampling rates conversion module, based on the above modules, we accomplished the work of data preprocessing in multiple instrument modes. The variable bandwidth analysis based on decimation filtering theory is one of the most important functions in DSA. We could increase the accuracy of our analysis in the frequency domain by changing the bandwidth of the spectrum.Design of built-in signal source: Firstly, based on the principle of DDS, this thesis accomplished the circuit and logic design of signal source in DSA. Such as sine, chirp, random noise and sweep signal can be generated by this build-in signal source. Secondly, by analyzing the needs of built-in signal source, we have designed the linkage control logic between the parameters of signal source and various instrument modes.In this thesis, the performance and specifications of data pre-process logic and built-in signal source are tested and analyzed on the hardware platform, the testing result shows that the design meets dynamic signal analyzer’s needs.