This site presents a stand alone C program and API called TransmissionLineTopCalc for the solution of networks of transmission lines and loads arranged in a tree topology. The TCL interpreter has been integrated into TransmissionLineTopCalc providing powerful optimization, tuning, and analysis capabilities.
The following are calculated among others:
- Node voltage/current/impedance
- Transmission line characteristic impedance/propagation constant
- Node impulse and frequency response, input impedance versus frequency
- Transmission line voltage distribution as a function of length
The transmission line network topology and parameters including loads are described by an ASCII file. The program contains built-in models for various transmission line types including dielectric and plasma slabs. These are also stored in an ASCII database. See the User Guide and Documentation for details including the algorithms.
The TransmissionLineTopCalc stand alone and developed TCL commands and API is written in C and are licensed under the GNU Lesser General Public License. The TCL scripts are covered by the GNU General Public License. The scripts are separate from the TransmissionLineTopCalc library. The intention is to provide all of the source code of TransmissionLineTopCalc as open source code with freedom to modify and enhance the code. All modifications and enhancements to theTransmissionLineTopCalc C API, TCL Commands must be published if distributed. Any distribution of the created code linking to the the TransmissionLineTopCalc API and TCL commands must include a statement showing links to the original theTransmissionLineTopCalc source code. The source code linking into the TransmissionLineTopCalc API or TCL commands does not need to be exposed.
TransmissionLineTopCalc has been developed by Sasan Ardalan since 1987 while at NC State University and has been incorporated into Capsim since 1989. The code has been enhanced and debugged through the years. The integration with TCL was done in August 2006. Susan Alexander working with Prof. Ardalan developed the recursive solution to the binary tree representation of transmission lines. Ken Shuey provided support for modeling power transmission lines. Gary Ybarra (now a professor at Duke University) working with Professor Ardalan extended TransmissionLineTopCalc to model plane wave propagation and turbulent Plasma's as encountered in the re-entry or aero assist braking off the atmosphere. Joseph Hall, an outstanding programmer, developed a graphical interface to the underlying C code while at NC State back in 1988.