A spectrum analyzer system with wide bandwidth and high frequency resolution based on chirp transform

With the advantages of low power consumption and high stability, chirp transform spectrometer (CTS) has become a powerful tool widely used in spectrum analysis today. In recent years, compared with other spectrum analyzers, CTS is limited by the lack of bandwidth, which severely restricts its application and development. In this article, a CTS system with a wide bandwidth is proposed. The chirp signal with 2 GHz bandwidth is generated by DAC and multiplier, and its dispersion characteristics are matched with a 1 GHz bandwidth surface acoustic wave (SAW) filter to build a spectrum analyzer with an analysis bandwidth of 1 GHz. Experimental results show that the system frequency resolution can reach up to 102 kHz, which is very close to the theoretical value (100 kHz).