Reference frame global coordinate system

We consider a right-handed Cartesian coordinate system OXYZ with a fixed spatial orientation. This reference frame will be referred to as the global coordinate system or the laboratory coordinate system. The direction of propagation of the vector plane wave is specified by the unit vector e, or equivalently, by the zenith and azimuth angles / and a, respectively (Fig. 1.2). The polarization state of the incident wave will be described in terms of the vertical polarization unit vector Cq, = x e /le x e l and the horizontal polarization vector e/3 = Ca x Bk. Note that other names for vertical polarization are TM polarization, parallel polarization and p polarization, while other names for horizontal polarization are TE polarization, perpendicular polarization and s polarization. 

Fig. 1.9. Reference frames (a) global coordinate system and (b) beam coordinate system...

Unless there is a macroscopic feature, such as an external electric field, defining the global axis system, the coordinate system is just an abstract frame of reference, and U(R, Q.) cannot depend on the relative orientation of the two... 

Load and displacement vectors in the global reference frame may be related to those defined in the local coordinate system by application of successive rotations from the local axes to the global axes ... 

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