Symmetric Three-Line (S3L) Circuit that Simplifies a Complicated Relation between the “Noise and Signal”, and “Common-, Normal-, and Antenna-Modes” (Part 1 Outline)

Abstract

We discuss a new circuit theory of multi-conductor transmission lines. According to the theorem, a symmetrical three-line (S3L) circuit gives an excellent noise reduction compared with a nominal two-line circuit. The practice of this S3L circuit was proposed by the author for power supplies of the twin synchrotrons of HIMAC (Heavy Ion Medical Accelerator in Chiba) 20 years ago, and the theory has recently been established by Prof. Hiroshi Toki, who has found a new principle of circuit theory based on the retarded potential and coefficients of potential. This theory provides a clear mathematical definition of common-, normal-, and antenna-modes for electromagnetic phenomena with a set of coupled integro differential equations among three modes. A signal contamination by noise is understood as coupling among these three modes. A relation between the “noise and signal”, and the three modes is generally complicated, however, such a relation is simplified very much in the case of the S3L circuit. The normal mode is decoupled from the common- and antenna-modes, so that a pure signal is obtained without any contamination of noise with a common-mode filter. This article describes the essence of both the practice and theory of the method in three parts; “Part 1 Outline”, “Part 2 Practice”, and “Part 3 Theory”.