chapter 1 Introduction
1.Wave: energy propagation through oscillating an amplitude of some physical parameter but not propagnating a medium.
Chapter 2 Transmission Line
1.transmission line: a line transmitting an electromagnetic wave. Coaxial Cable.
load impedance 负载阻抗，用Z表示，交变电流中的电阻，单位是欧姆。
voltage reflection coefficient 电压反射系数。