Cao, ConghuiYang, HuaZhang, HaoWang, YanGulliver, Thomas Aaron2019-01-242019-01-2420182018Cao, C., Yang, H., Zhang, H., Wang, Y. & Gulliver, T.A. (2018). Passive Detection of Low-Altitude Signal Sources Using an Improved Cross-Correlation Algorithm. Applied Sciences, 8(12), 2348. https://doi.org/10.3390/app8122348https://doi.org/10.3390/app8122348http://hdl.handle.net/1828/10532The passive detection of low-altitude signal sources is studied using an improved cross-correlation method in the time–frequency domain. A matching template is designed for signal cross-correlation, and a cross-correlation threshold is used to determine whether a signal source is present or not. An improved cross-correlation method is also proposed to estimate the direction of arrival and communication frequency of a signal source. Furthermore, the distance and signal-to-noise ratio are estimated using an energy detector. Outdoor data from a bridge in the Jimo District, Qingdao, and indoor data from a research laboratory are used for performance evaluation. The results obtained show that the proposed method can provide better passive detection of low-altitude signal sources compared to several well-known algorithms in the literature. In addition, this method is more suitable for long-distance detection.ensignal detectionlow-altitude signal sourceunmanned aerial vehicle (UAV)cross-correlationtime–frequency analysisArticleDepartment of Electrical and Computer Engineering