Table 3.4. Some Frequently Used Relationships

= o "	is conductivity in siemens/meter
	o = 8.85 x 10-12 F/m: permittivitiy of free space
	" is the imaginary part of complex relative permittivity
= 2 f	is radian frequency in radians/second
	f is frequency in hertz
tan = "/'	tan is the loss tangent
P = | E |2	P is density of absorbed power at a point in watts/cubic meter
	is conductivity in siemens/meter at the point
	|E | is rms electric-field intensity in rms volts/meter
D = E	D is electric-flux density in coulombs/square meter
	is permittivity in farads/meter
	E is electric-field intensity in volts/meter
B = H	B is magnetic-flux density in tesla
	is permeability in henry/meter
	H is magnetic-field intensity in amperes/meter
o=8.85 x 10-12 F/m	o is the permittivity of free space
o = 4 x 10-7 H/m	o is the permeability of free space
f = 1/T	f is frequency in hertz
	T is period in seconds
= v/f	is wavelength in meters
	v is velocity of propagation in meters/second
	f is frequency in hertz
	E/H is the wave impedance in ohms
E/H = 377 ohms in free space	E is the magnitude of the electric-field intensity in volts/meter
	H is the magnitude of the magnetic-field intensity in amperes/meter
	v is the velocity of propagation in meters/second
v = 3 x 108 m/s in free space	is the premeability in henry/meter
	is the permittivity in farad/meter
<P> = <E x H>	<P> is the time-averaged Poynting's vector in watts/square meter
	E is the electric-field intensity in rms volts/meter
	H is the magnetic-field intensity in rms amperes/meter
P = E2/377	P is the magnitude of the time-average Poynting vector for a planewave in free space
	E is the magnitude of the electric-field intensity in rms volts/meter
	377 is the wave impedance of free space in ohms
S = Emax/Emin	S is the standing-wave ratio (unitless)
	E max is the maximum value of the magnitude of the electric-field intensity anywhere along the wave
	E min is the minimum value of the magnitude of the electric-field intensity anywhere along the wave
S = (1 + ) / (1 - )	S is the standing-wave ratio (unitless)
	is the magnitude of the reflection coefficient (ratio of reflected E-field to incident E-field)
	is the skin depth in meters
	' is the real part of the permittivity
	" is the imaginary part of the permittivity
	f is the frequency in MHz
SAR = |E| 2 / m	SAR is the local specific absorption rate in watts/kilogram
	is the conductivity in siemens/meter
	|E| is the electric-field strength in rms volts/meter
	m is the mass density in kilograms/cubic meter
	fo is the resonant frequency in hertz of the SAR for E polarization
	is the average length of the absorbing object
	d is the average diameter of the absorbing object
	F is the rms value of the periodic function f (t)
	T is the period of the function
G = gp /	G is the rms value of a sinusoid
	Gp is the peak value of the sinusoid
d = 2L2/	d is the approximate distance from an antenna at which the n ear fields become negligible and the fields are approximately far fields
	L is the largest dimension of the antenna
	is the wavelength

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