In addition, we have a new velocity field V, which has the role of indicating the direction and speed of development of the energy flow (a sort of generalization of the

Poynting vector).

The on-surface longitudinal

Poynting vector of a 10-wavelength, center-fed dipole consequently also decays with distance as shown in Figure 3 [17].

Figure 7 demonstrates magnetic field [H.sub.z] (Figure 7(a)) and

Poynting vector [P.sub.y] (Figure 7(b)) pattern as a function on [k.sub.x] and y.

First, Finite Difference Time Domain (FDTD) simulation results at known values of the implant depth are used to obtain the magnitude of the

Poynting vector data at distances on and off the body surface, after a UWB signal is applied at the input of the implanted sensor antenna.

It has been obtained that a real part of the

Poynting vector normal component of a wave propagating in an anisotropic medium is not equal to zero when an incident wave propagates tangentially to an interface between the media.

Using the computed electromagnetic field values, the spatial distribution of the surface current density excited on the reflector and on the dipole arms, as well as the real part of the

Poynting vector, and the radiation patterns (see Figure 9) have been evaluated at the working frequencies of 5 GHz, 6 GHz, and 7 GHz, both for the antenna with and without metal reflector.

The linear momentum density is given by the

Poynting vector E x B and the angular momentum is the cross product of the

Poynting vector with the position vector.

This use of the right hand rule is called the

Poynting vector.

To further understand the effects of LSP on different polarization of dipole source, the magnitude of

Poynting vector at the wavelength of 402.7 nm and 460 nm is shown in Figures 6 and 7 in the case of [h.sub.NR] = 400 nm and [d.sub.Ag] =100 nm.

This choice can be expressed by means of the

Poynting vector of (E, H) evaluated at [c.sub.n] as

[r.sub.k] = [[[u.sub.k], [v.sub.k], [w.sub.k]].sup.T] = [[sin [[theta].sub.k] cos [[phi].sub.k], sin [[theta].sub.k] sin [[phi].sub.k], cos [[theta].sub.k]].sup.T] denotes the normalized

Poynting vector. [(x).sup.T] denotes the transpose.

To this end, let us consider the EM field distribution in the periodic structure and the imaginary part of the

Poynting vector. It is generally known, that the Poynting energy flux vector S is a complex quantity [39, 40]