In order to realize high-resolution target imaging with varying depth by Fourier telescope,the basic imaging equations are used and the study is proceeded with the method of intuitively qualitative analysis at first,and then with the method of computer-aided quantitative analysis. The longest echo time delay of targets with meter-order depth is 6.7 ns according to principle analysis. Qualitative analysis points out that Fourier telescope can image targets of meter-order depth when the signal period is far longer than 6.7 ns;and the imaging quality will decline when the signal period is about 6.7 ns or shorter. Quantitative analysis has compared the reconstructed results and Strehl values when the ratios of largest echo delay and signal period are between 0 and 1/8,and identified reconstructed target images can be obtained when the ratio is smaller than 1/32. After that,the reconstructed results and Strehl values have been compared when the segments are 2,4 and 8,and then the varying depth of target has no effect on imaging when the signal period is far longer than largest delay. The identified image can be reconstructed by signals when heterodyne frequency is less than 466 kHz according to the simulation of targets with depth less than 10 meters.