When measuring the radar carrier frequency (RCF) via DFT, the frequency resolution is 1/2N, where N is the length of the DFT sequence. To improve the frequency measurement precision, the length of the DFT sequence must be increased, thus the computation is increased too. This paper is intended to introduce a modified algorithm, experimental results of which indicate that 10 to 100 times more measurement precision can be achieved while keeping computation fixed.