修改GNURadio中的频谱分析工具usrp_fft.py调用的C++模块gr_fft_vcc_fftw.cc，实现频谱的数据的存储，附有画图的matlab程序和实现的效果图，实现频谱数据分析需要。-Changes in the spectrum analysis tool GNURadio usrp_fft.py call C++ module gr_fft_vcc_fftw.cc, to achieve the spectrum of data storage, with a drawing program and achieve results matlab graph, the spectral data analysis needs.