Identification of Equivalent Circuit Based on Polygon Network for Nonreciprocal Lossy N-Port Device

Abstract

Abstract-In this paper, a technique to identify/synthesize an equivalent circuit of nonreciprocal lossy N -port device is presented. The technique joins the classical procedure discussed in the '60s to the polygon network recently proposed in the literature, which permits to draw an equivalent circuit for reciprocal lossless N -port device in a very simple way. The identification is applied to two microwave devices, a reciprocal lossy iris in WR90 waveguide and a 3-port nonreciprocal lossy circulator. The proposed equivalent circuit could give some information about the agreement of the manufactured device and its design, which usually is developed in the hypothesis of ideal lossless components.

Analysis of ``False Non Reciprocity'' in 2-Port Vna Measurements of Reciprocal Devices

“…To verify the entity of the actual errors, we can evaluate the amplitude of the gyrators amplitudes, shown in Figs. 3(a) IF bandwidth [4][5][6][7][8][9][10][11]. The obtained values for χ, ξ confirm that the "false non-reciprocity" for the lossless part, χ, is greater than that of the lossy part, ξ, because the losses of the analyzed device are low.…”

“…We can also evaluate the actual values of r ij , x ij of the lossy and lossless parts of the ζ-matrix [11], here not shown for brevity, and reconstruct the "reciprocal" S-matrix in Eq. (12), S rec , from Eqs.…”

“…(4). A recent synthesis procedure has been analyzed in [11], but it is not reported here, because the goal of the paper is to evaluate how to correct the "false non-reciprocity" due to experimental measurements.…”

“…Obviously, we can completely delete the "false experimental non-reciprocity" effects evaluating the amplitudes of χ and ξ by the measured S-matrix, performing the steps discussed in [4][5][6][7][8][9][10][11] that consist in evaluating the impedance matrices in Eq. (2) and from Eqs.…”