/* * indq.cpp - Lossy inductor class implementation * * Copyright (C) 2015 Andres Martinez-Mera * * This is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this package; see the file COPYING. If not, write to * the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, * Boston, MA 02110-1301, USA. * */ #if HAVE_CONFIG_H # include #endif #include "component.h" #include "indq.h" #include "iostream" using namespace qucs; //-------------------------------------------------------- // References: // [1] Bahl. Lumped elements for RF and microwave circuits. Pg 22 indq::indq () : circuit (2) { type = CIR_INDQ; } // calculate equivalent series impedance of the lossy inductor void indq::calcZs(nr_double_t frequency) { nr_double_t L = getPropertyDouble ("L"); nr_double_t Q = getPropertyDouble ("Q"); nr_double_t f = getPropertyDouble ("f"); nr_double_t Xl = 2.*pi*frequency*L; nr_double_t Rs = 0.0; if ((f != 0.0) && (Q != 0.0) && (frequency!=0)) { // Q=0 or f=0 can be used to force ideal behavior (no losses) nr_double_t Qf = Q; if (!strcmp (getPropertyString ("Mode"), "Linear")) Qf *= frequency/f; if (!strcmp (getPropertyString ("Mode"), "SquareRoot")) Qf *= qucs::sqrt(frequency/f); Rs = Xl / Qf; } Zs = nr_complex_t (Rs, Xl); } //------------------------------------------------------------------ // This function calculates the S-parameters matrix of a lossy inductance // Q = 2*pi*f*L/Rs // where Rs is the series resistance and L the inductance void indq::calcSP (nr_double_t frequency) { // calculate element series impedance calcZs(frequency); nr_complex_t z = Zs / z0; setS (NODE_1, NODE_1, z / (z + 2.0)); setS (NODE_2, NODE_2, z / (z + 2.0)); setS (NODE_1, NODE_2, 2.0 / (z + 2.0)); setS (NODE_2, NODE_1, 2.0 / (z + 2.0)); } void indq::calcNoiseSP (nr_double_t) { // calculate noise using Bosma's theorem nr_double_t T = getPropertyDouble ("Temp"); matrix s = getMatrixS (); matrix e = eye (getSize ()); setMatrixN (celsius2kelvin (T) / T0 * (e - s * transpose (conj (s)))); } void indq::initDC (void) { //Short circuit setVoltageSources (1); allocMatrixMNA (); voltageSource (VSRC_1, NODE_1, NODE_2); } void indq::calcDC (void) { clearY (); } void indq::initAC (void) { nr_double_t L = getPropertyDouble ("L"); // for non-zero inductance usual MNA entries if (L != 0.0) { setVoltageSources (0); allocMatrixMNA (); } // for zero inductance create a zero voltage source else { initDC (); calcDC (); } } void indq::initSP(void) { allocMatrixS (); } void indq::calcAC (nr_double_t frequency) { // calculate element series impedance calcZs(frequency); // for non-zero impedance usual MNA entries if (Zs != 0.0) { nr_complex_t y11 = 1./Zs; nr_complex_t y12 = -1./Zs; nr_complex_t y21 = -1./Zs; nr_complex_t y22 = 1./Zs; setY (NODE_1, NODE_1, y11); setY (NODE_2, NODE_2, y22); setY (NODE_1, NODE_2, y12); setY (NODE_2, NODE_1, y21); } } void indq::calcNoiseAC (nr_double_t) { // calculate noise using Bosma's theorem nr_double_t T = getPropertyDouble ("Temp"); setMatrixN (4 * celsius2kelvin (T) / T0 * real (getMatrixY ())); } // properties PROP_REQ [] = { { "L", PROP_REAL, { 1e-9, PROP_NO_STR }, PROP_POS_RANGE }, { "Q", PROP_REAL, { 100, PROP_NO_STR }, PROP_POS_RANGE }, { "f", PROP_REAL, { 100e6, PROP_NO_STR }, PROP_NO_RANGE }, { "Mode", PROP_STR, { PROP_NO_VAL, "Linear" }, PROP_RNG_STR3 ("Linear", "SquareRoot", "Constant") }, PROP_NO_PROP }; PROP_OPT [] = { { "Temp", PROP_REAL, { 26.85, PROP_NO_STR }, PROP_MIN_VAL (K) }, PROP_NO_PROP }; struct define_t indq::cirdef = { "INDQ", 2, PROP_COMPONENT, PROP_NO_SUBSTRATE, PROP_LINEAR, PROP_DEF };