This paper introduces the adaptive step intermittent chaotic oscillator for the first time to solve the problems of low resolution of close frequency and interharmonics and weak anti-noise ability, and describes two means for estimating frequency. The method of using intermittent chaotic oscillator for frequency estimation is proposed. Besides a simplified method of sine signal amplitude and phase is put forward which is based on phase jump chaotic oscillator for estimating the amplitude and phase of harmonic and interharmonics. Finally, a simulation result of a analog signal is used for verifying the availability and accuracy of the detection and estimation method proposed.