A Linear Method for Extracting the Amplitude of a Sinusoidal Signal

ABSTRACT The amplitude extraction of sinusoidal signals is a very important task in many engineering applications; existing extraction methods demonstrate poor performance due to their limited extraction accuracy. This paper presents a method, which does not require a power of two sampling points, for linearly extracting the amplitude of sinusoidal signals and develops a corresponding hardware system. The system can autonomously generate fixed‐frequency sinusoidal signals induced through an electromagnetic induction coil, which are subsequently amplified and are sampled by the acquisition card. Additionally, the system features a standard signal input interface, enabling flexible input of sinusoidal signals with different frequencies. Both simulation and real signal sampling data experiments show that it does not require complex iterative calculations and has the advantages of fast speed and high accuracy, and can be used in the scenarios requiring high real‐time performance and extraction precision.