-- -- BUGS -- -- Copyright (C) 2003, 2004, 2005 Stefan Jahn -- -- 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. -- This file is intended to collect all known bugs (fixed or unfixed) in this package. We will consider fixing these sooner or later. Please send Qucs bug reports to . Bug: B0001 From: Stefan Jahn State: fixed (2004-10-19/stefan) Date: 2004-09-01 Description: Parallel coupled microstrip models do not work. In fact the characteristic impedances for even and odd mode are wrong. Fix: Found the appropriate publication by Kirschning. Bug: B0002 From: Stefan Jahn State: fixed (2005-05-12/stefan) Date: 2005-03-01 Description: Depending on the netlist input order it may occur that a DC analysis converges or does not converge (under-determined equation system?). Fix: The example netlists I had for this case are almostly rank-deficient MNA matrices. Thus another, numerically more stable, matrix decomposition algorithm has been implemented: the QR decomposition using Householder transformations. The solution algorithm can now be chosen. The new algorithm is now able to solve the test-cases - LU decomposition was not. Bug: B0003 From: Stefan Jahn State: fixed (2005-03-08/stefan) Date: 2005-03-01 Description: Noise correlation matrices of microstrip components can't be calculated assuming a simple attenuation because of the transition time effects. Fix: The calculation is performed using Bosma's theorem. Bug: B0004 From: Stefan Jahn State: fixed (2005-03-08/stefan) Date: 2005-03-01 Description: AC output resistance of the BJT model is much too high. Fix: Use conservative small signal equivalent circuit description instead of the 'NEWSGP' which works nice for DC calculation anyway. Bug: B0005 From: Stefan Jahn State: unfixed Date: 2007-12-30 Description: Empty subcircuit definitions in conjunction with duplicate nodes in the nodelist (shorted nodes) cause the simulator to withdraw the netlist.