Design and Analysis of N-path Filter for Radio Frequencies

Due to the growth of wireless communication many communication frequencies have grown increasingly dense. This density requires higher Q-factor to receive only the signal of interest. With the rise of smaller integrated circuits previous solutions used for filtering have become viable again. This paper explores whether the N-path filter is viable in the modern day for radio frequency receiver purposes. A non-differential N-path filter was created by utilizing Cadence Virtuoso with a working center frequency range of 750MHz to 1GHz while using TSMC technology. The desired quality factor of over 1,000 was reached while maintaining a total area of 800 by 800 micrometers. Through the analysis of the N-path filter new techniques for mixed signal analysis were used for simulation. This included parametric analysis in Cadence ADE-L and additional analysis in MATLAB, and the addition of a bootstrapping circuit to decrease simulation time. Future applications regarding analyzing mixed signals could use these methods to provide frequency response data and automated processing