/* * twistedpair.h - twisted pair class definition * * Copyright (C) 2011 Michael Margraf * Modifications 2011 for Kicad: Jean-Pierre Charras * * This program 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 of the License, or (at * your option) any later version. * * This program 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. * */ #include #include #include #include #include "twistedpair.h" #include "units.h" TWISTEDPAIR::TWISTEDPAIR() : TRANSLINE() { m_Name = "TwistedPair"; Init(); } /** * \f$ \theta = \arctan\left( T \cdot \pi \cdot D_{out} \right) \f$ * * Where : * - \f$ \theta \f$ : pitch angle * - \f$ T \f$ : Number of twists per unit length * - \f$ D_{out} \f$ : Wire diameter with insulation * * \f$ e_{eff} = e_{env} \cdot \left( 0.25 + 0.0007 \cdot \theta^2 \right)\cdot\left(e_r-e_{env}\right) \f$ * * Where : * - \f$ e_{env} \f$ : relative dielectric constant of air ( or some other surronding material ), * - \f$ e_r \f$ : relative dielectric constant of the film insulation, * - \f$ e_{eff} \f$ : effective relative dielectric constant * * \f$ Z_0 = \frac{Z_\mathrm{VACUUM}}{\pi \cdot \sqrt{e_{eff}}}\cosh^{-1}\left(\frac{D_{out}}{D_{in}}\right) \f$ * * - \f$ Z_0 \f$ : line impedance * - \f$ Z_\mathrm{VACUUM} \f$ : vacuum impedance * - \f$ D_{in} \f$ : Wire diameter without insulation * * Reference for above equations : * * [1] : P. Lefferson, ``Twisted Magnet Wire Transmission Line,'' * IEEE Transactions on Parts, Hybrids, and Packaging, vol. PHP-7, no. 4, pp. 148-154, Dec. 1971. * * The following URL can be used as reference : http://qucs.sourceforge.net/tech/node93.html **/ void TWISTEDPAIR::calcAnalyze() { double tw = atan( m_parameters[TWISTEDPAIR_TWIST_PRM] * M_PI * m_parameters[PHYS_DIAM_OUT_PRM] ); // pitch angle m_parameters[EPSILON_EFF_PRM] = m_parameters[TWISTEDPAIR_EPSILONR_ENV_PRM] + ( 0.25 + 0.0007 * tw * tw ) * ( m_parameters[EPSILONR_PRM] - m_parameters[TWISTEDPAIR_EPSILONR_ENV_PRM] ); m_parameters[Z0_PRM] = ZF0 / M_PI / sqrt( m_parameters[EPSILON_EFF_PRM] ) * acosh( m_parameters[PHYS_DIAM_OUT_PRM] / m_parameters[PHYS_DIAM_IN_PRM] ); m_parameters[LOSS_CONDUCTOR_PRM] = 10.0 / log( 10.0 ) * m_parameters[PHYS_LEN_PRM] / m_parameters[SKIN_DEPTH_PRM] / m_parameters[SIGMA_PRM] / M_PI / m_parameters[Z0_PRM] / ( m_parameters[PHYS_DIAM_IN_PRM] - m_parameters[SKIN_DEPTH_PRM] ); m_parameters[LOSS_DIELECTRIC_PRM] = 20.0 / log( 10.0 ) * m_parameters[PHYS_LEN_PRM] * M_PI / C0 * m_parameters[FREQUENCY_PRM] * sqrt( m_parameters[EPSILON_EFF_PRM] ) * m_parameters[TAND_PRM]; m_parameters[ANG_L_PRM] = 2.0 * M_PI * m_parameters[PHYS_LEN_PRM] * sqrt( m_parameters[EPSILON_EFF_PRM] ) * m_parameters[FREQUENCY_PRM] / C0; // in radians } // ------------------------------------------------------------------- void TWISTEDPAIR::show_results() { setResult( 0, m_parameters[EPSILON_EFF_PRM], "" ); setResult( 1, m_parameters[LOSS_CONDUCTOR_PRM], "dB" ); setResult( 2, m_parameters[LOSS_DIELECTRIC_PRM], "dB" ); setResult( 3, m_parameters[SKIN_DEPTH_PRM] / UNIT_MICRON, "µm" ); } void TWISTEDPAIR::showAnalyze() { setProperty( Z0_PRM, m_parameters[Z0_PRM] ); setProperty( ANG_L_PRM, m_parameters[ANG_L_PRM] ); // Check for errors if( !std::isfinite( m_parameters[Z0_PRM] ) || m_parameters[Z0_PRM] < 0 ) setErrorLevel( Z0_PRM, TRANSLINE_ERROR ); if( !std::isfinite( m_parameters[ANG_L_PRM] ) || m_parameters[ANG_L_PRM] < 0 ) setErrorLevel( ANG_L_PRM, TRANSLINE_ERROR ); // Find warnings to display - physical parameters if( !std::isfinite( m_parameters[PHYS_DIAM_IN_PRM] ) || m_parameters[PHYS_DIAM_IN_PRM] <= 0.0 ) setErrorLevel( PHYS_DIAM_IN_PRM, TRANSLINE_WARNING ); if( !std::isfinite( m_parameters[PHYS_DIAM_OUT_PRM] ) || m_parameters[PHYS_DIAM_OUT_PRM] <= 0.0 ) { setErrorLevel( PHYS_DIAM_OUT_PRM, TRANSLINE_WARNING ); } if( m_parameters[PHYS_DIAM_IN_PRM] > m_parameters[PHYS_DIAM_OUT_PRM] ) { setErrorLevel( PHYS_DIAM_IN_PRM, TRANSLINE_WARNING ); setErrorLevel( PHYS_DIAM_OUT_PRM, TRANSLINE_WARNING ); } if( !std::isfinite( m_parameters[PHYS_LEN_PRM] ) || m_parameters[PHYS_LEN_PRM] < 0.0 ) setErrorLevel( PHYS_LEN_PRM, TRANSLINE_WARNING ); } void TWISTEDPAIR::showSynthesize() { if( isSelected( PHYS_DIAM_IN_PRM ) ) setProperty( PHYS_DIAM_IN_PRM, m_parameters[PHYS_DIAM_IN_PRM] ); else if( isSelected( PHYS_DIAM_OUT_PRM ) ) setProperty( PHYS_DIAM_OUT_PRM, m_parameters[PHYS_DIAM_OUT_PRM] ); setProperty( PHYS_LEN_PRM, m_parameters[PHYS_LEN_PRM] ); // Check for errors if( !std::isfinite( m_parameters[PHYS_DIAM_IN_PRM] ) || m_parameters[PHYS_DIAM_IN_PRM] <= 0.0 ) { if( isSelected( PHYS_DIAM_IN_PRM ) ) setErrorLevel( PHYS_DIAM_IN_PRM, TRANSLINE_ERROR ); else setErrorLevel( PHYS_DIAM_IN_PRM, TRANSLINE_WARNING ); } if( !std::isfinite( m_parameters[PHYS_DIAM_OUT_PRM] ) || m_parameters[PHYS_DIAM_OUT_PRM] <= 0.0 ) { if( isSelected( PHYS_DIAM_OUT_PRM ) ) setErrorLevel( PHYS_DIAM_OUT_PRM, TRANSLINE_ERROR ); else setErrorLevel( PHYS_DIAM_OUT_PRM, TRANSLINE_WARNING ); } if( m_parameters[PHYS_DIAM_IN_PRM] > m_parameters[PHYS_DIAM_OUT_PRM] ) { if( isSelected( PHYS_DIAM_IN_PRM ) ) setErrorLevel( PHYS_DIAM_IN_PRM, TRANSLINE_ERROR ); else if( isSelected( PHYS_DIAM_OUT_PRM ) ) setErrorLevel( PHYS_DIAM_OUT_PRM, TRANSLINE_ERROR ); } if( !std::isfinite( m_parameters[PHYS_LEN_PRM] ) || m_parameters[PHYS_LEN_PRM] < 0.0 ) setErrorLevel( PHYS_LEN_PRM, TRANSLINE_ERROR ); // Check for warnings if( !std::isfinite( m_parameters[Z0_PRM] ) || m_parameters[Z0_PRM] < 0 ) setErrorLevel( Z0_PRM, TRANSLINE_WARNING ); if( !std::isfinite( m_parameters[ANG_L_PRM] ) || m_parameters[ANG_L_PRM] < 0 ) setErrorLevel( ANG_L_PRM, TRANSLINE_WARNING ); } #define MAX_ERROR 0.000001 // ------------------------------------------------------------------- void TWISTEDPAIR::calcSynthesize() { if( isSelected( PHYS_DIAM_IN_PRM ) ) minimizeZ0Error1D( &( m_parameters[PHYS_DIAM_IN_PRM] ) ); else minimizeZ0Error1D( &( m_parameters[PHYS_DIAM_OUT_PRM] ) ); }