kicad/pcb_calculator/transline/coax.cpp

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/*
* coax.cpp - coaxial class implementation
*
* Copyright (C) 2001 Gopal Narayanan <gopal@astro.umass.edu>
* Copyright (C) 2002 Claudio Girardi <claudio.girardi@ieee.org>
* Copyright (C) 2005, 2006 Stefan Jahn <stefan@lkcc.org>
*
* 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.
*
*/
/*
* coax.c - Puts up window for microstrip and
* performs the associated calculations
*/
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include "coax.h"
#include "units.h"
COAX::COAX() : TRANSLINE()
{
m_Name = "Coax";
Init();
}
double COAX::alphad_coax()
{
double ad;
ad = ( M_PI / C0 ) * m_parameters[FREQUENCY_PRM] * sqrt( m_parameters[EPSILONR_PRM] )
* m_parameters[TAND_PRM];
ad = ad * 20.0 / log( 10.0 );
return ad;
}
double COAX::alphac_coax()
{
double ac, Rs;
Rs = sqrt( M_PI * m_parameters[FREQUENCY_PRM] * m_parameters[MURC_PRM] * MU0
/ m_parameters[SIGMA_PRM] );
ac = sqrt( m_parameters[EPSILONR_PRM] )
* ( ( ( 1 / m_parameters[PHYS_DIAM_IN_PRM] ) + ( 1 / m_parameters[PHYS_DIAM_OUT_PRM] ) )
/ log( m_parameters[PHYS_DIAM_OUT_PRM] / m_parameters[PHYS_DIAM_IN_PRM] ) )
* ( Rs / ZF0 );
ac = ac * 20.0 / log( 10.0 );
return ac;
}
/**
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* \f$ Z_0 = \frac{Z_{0_{\mathrm{vacuum}}}}{\sqrt{\epsilon_r}}\log_{10}\left( \frac{D_{\mathrm{out}}}{D_{\mathrm{in}}}\right) \f$
*
* \f$ \lambda_g = \frac{c}{f \cdot \sqrt{ \epsilon_r \cdot \mu_r}} \f$
*
* \f$ L_{[\mathrm{rad}]} = \frac{ 2\pi\cdot L_{[\mathrm{m}]}}{\lambda_g} \f$
* */
void COAX::calcAnalyze()
{
double lambda_g;
m_parameters[Z0_PRM] =
( ZF0 / 2 / M_PI / sqrt( m_parameters[EPSILONR_PRM] ) )
* log( m_parameters[PHYS_DIAM_OUT_PRM] / m_parameters[PHYS_DIAM_IN_PRM] );
lambda_g = ( C0 / ( m_parameters[FREQUENCY_PRM] ) )
/ sqrt( m_parameters[EPSILONR_PRM] * m_parameters[MUR_PRM] );
/* calculate electrical angle */
m_parameters[ANG_L_PRM] =
( 2.0 * M_PI * m_parameters[PHYS_LEN_PRM] ) / lambda_g; /* in radians */
}
/**
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* \f$ D_{\mathrm{in}} = D_{\mathrm{out}} \cdot e^{-\frac{Z_0*\sqrt{\epsilon_r}}{2\pi \cdot Z_{0_{\mathrm{vacuum}}}}} \f$
*
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* \f$ D_{\mathrm{out}} = D_{\mathrm{in}} \cdot e^{ \frac{Z_0*\sqrt{\epsilon_r}}{2\pi \cdot Z_{0_{\mathrm{vacuum}}}}} \f$
*
* \f$ \lambda_g = \frac{c}{f \cdot \sqrt{ \epsilon_r \cdot \mu_r}} \f$
*
* \f$ L_{[\mathrm{m}]} = \frac{ \lambda_g cdot L_{[\mathrm{m}]}}{2\pi} \f$
* */
void COAX::calcSynthesize()
{
double lambda_g;
if( isSelected( PHYS_DIAM_IN_PRM ) )
{
/* solve for din */
m_parameters[PHYS_DIAM_IN_PRM] =
m_parameters[PHYS_DIAM_OUT_PRM]
/ exp( m_parameters[Z0_PRM] * sqrt( m_parameters[EPSILONR_PRM] ) / ZF0 * 2 * M_PI );
}
else if( isSelected( PHYS_DIAM_OUT_PRM ) )
{
/* solve for dout */
m_parameters[PHYS_DIAM_OUT_PRM] =
m_parameters[PHYS_DIAM_IN_PRM]
* exp( m_parameters[Z0_PRM] * sqrt( m_parameters[EPSILONR_PRM] ) / ZF0 * 2 * M_PI );
}
lambda_g = ( C0 / ( m_parameters[FREQUENCY_PRM] ) )
/ sqrt( m_parameters[EPSILONR_PRM] * m_parameters[MUR_PRM] );
/* calculate physical length */
m_parameters[PHYS_LEN_PRM] = ( lambda_g * m_parameters[ANG_L_PRM] ) / ( 2.0 * M_PI ); /* in m */
}
void COAX::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 COAX::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 );
}
}
/*
* show_results() - show results
*/
void COAX::show_results()
{
int m, n;
char text[256], txt[256];
m_parameters[LOSS_DIELECTRIC_PRM] = alphad_coax() * m_parameters[PHYS_LEN_PRM];
m_parameters[LOSS_CONDUCTOR_PRM] = alphac_coax() * m_parameters[PHYS_LEN_PRM];
setResult( 0, m_parameters[EPSILONR_PRM], "" );
setResult( 1, m_parameters[LOSS_CONDUCTOR_PRM], "dB" );
setResult( 2, m_parameters[LOSS_DIELECTRIC_PRM], "dB" );
n = 1;
m_parameters[CUTOFF_FREQUENCY_PRM] =
C0
/ ( M_PI * ( m_parameters[PHYS_DIAM_OUT_PRM] + m_parameters[MUR_PRM] ) / (double) n );
if( m_parameters[CUTOFF_FREQUENCY_PRM] > m_parameters[FREQUENCY_PRM] )
strcpy( text, "none" );
else
{
strcpy( text, "H(1,1) " );
m = 2;
m_parameters[CUTOFF_FREQUENCY_PRM] =
C0
/ ( 2 * ( m_parameters[PHYS_DIAM_OUT_PRM] - m_parameters[MUR_PRM] )
/ (double) ( m - 1 ) );
while( ( m_parameters[CUTOFF_FREQUENCY_PRM] <= m_parameters[FREQUENCY_PRM] ) && ( m < 10 ) )
{
sprintf( txt, "H(n,%d) ", m );
strcat( text, txt );
m++;
m_parameters[CUTOFF_FREQUENCY_PRM] =
C0
/ ( 2 * ( m_parameters[PHYS_DIAM_OUT_PRM] - m_parameters[MUR_PRM] )
/ (double) ( m - 1 ) );
}
}
setResult( 3, text );
m = 1;
m_parameters[CUTOFF_FREQUENCY_PRM] =
C0 / ( 2 * ( m_parameters[PHYS_DIAM_OUT_PRM] - m_parameters[MUR_PRM] ) / (double) m );
if( m_parameters[CUTOFF_FREQUENCY_PRM] > m_parameters[FREQUENCY_PRM] )
strcpy( text, "none" );
else
{
strcpy( text, "" );
while( ( m_parameters[CUTOFF_FREQUENCY_PRM] <= m_parameters[FREQUENCY_PRM] ) && ( m < 10 ) )
{
sprintf( txt, "E(n,%d) ", m );
strcat( text, txt );
m++;
m_parameters[CUTOFF_FREQUENCY_PRM] =
C0
/ ( 2 * ( m_parameters[PHYS_DIAM_OUT_PRM] - m_parameters[MUR_PRM] )
/ (double) m );
}
}
setResult( 4, text );
}