A digital tone decoder based on a modified Goertzel algorithm

According to the analysis of Goertzel algorithm, this paper presents a series of methods and measures, which are from both hardware and software, to improve the performance of the system. We implemented a tone decoder with low-cost, small package, mixed-signal chips, and it provides with its advantages of high accuracy, small size, good temperature performance and high universality. This decoder is used in many communication equipments now.