Wave per unit distance (typically per meter), can be associated with the wavelength by the relation The period formula_33 is the time for one complete cycle of an oscillation of a wave. The frequency formula_34 is the number of periods per unit time (per second) and is typically measured in hertz denoted as Hz. These are related by: In other words, the frequency and period of a wave are reciprocals. The angular frequency formula_28 represents the frequency in radians per second. It is related to the frequency or period by The wavelength formula_30 of a sinusoidal waveform traveling at constant speed
Propagation constant of transmission lines, the term transmission coefficient has a different meaning despite the similarity of name: it is the companion of the reflection coefficient. The propagation constant, symbol formula_1, for a given system is defined by the ratio of the complex amplitude at the source of the wave to the complex amplitude at some distance "x", such that, Since the propagation constant is a complex quantity we can write: where That "β" does indeed represent phase can be seen from Euler's formula: which is a sinusoid which varies in phase as "θ" varies but does not vary in amplitude because