Automatic measurement of complex dielectric constant and permeability at microwave frequencies

Synthesis of ferrofluid based nanoarchitectured polypyrrole composites and its application for electromagnetic shielding

“…To further analyze the shielding mechanism, complex permittivity (ε r ¼ ε 0 À jε 00 ) and permeability (m r ¼ m 0 À jm 00 ) have been calculated using scattering parameters (S 11 & S 21 ) based on the calculations given in Nicholson, Ross and Weir method [39,40] and demonstrated in Fig. 8.…”

Transmission

“…Since the Laplace transform of eq (3.4) is G{s) = Y.^n 1 S-\-ttn + jhn (3.5) for stability (no increasing time domain exponentials) there can be no poles or zeros in the right half-side of the 5-plane [37], [38]. In order to maintain the reality of e (5) [7] or Weir [6] 12 13 Frequency (GHz) Frequerx:y (GHz) (a) [26] and only the most essential details will be presented here.…”

“…Equation (4.8) transforms Then for independent measurements on the two samples we havê 11(1) = ffj^> (4)(5)(6)(7)(8)(9)(10)(11)(12) and Port1…”

“…In these cases we have four unknown quantities (complex permittivity and permeability) and therefore require four independent real equations to solve for these variables. These equations can be generated by Most of the present transmission-line techniques [2,3,4], with some variations, are based on the procedure developed by Nicolson and Ross [5] and Weir [6] for obtaining 2-port, off-resonance, broadband measurements of permeability and permittivity. In the Nicolson-Ross-Weir (NRW) procedure the equations for the scattering parameters are combined in such a fashion that the system of equations can be decoupled.…”

“…The S-parameters measured by the device reference planes are related to the S-parameters at the sample face 5' by [26] 5-555 , (2.29) (2.35) are the respective reference plane transformations. Equations (2.31) through (2.33) are not new and are derived in detail elsewhere [5,28] Nicolson and Ross [5], and Weir [6] …”