nec2small(1) Numerical Electromagnetics Code (Antenna Modelling Program)

Other Alias



nec2small [INPUT] [OUTPUT]


nec2, is a versatile numerical Boundary Element Method (commonly called Method of Moments) antenna modelling code for the analysis of antennas and other metal structures. It solves the integral equations for the currents induced on the structure by sources or incident fields. The structure may either be excited by voltage sources on the structure, or by an incident plane wave of either elliptic or linear polarisation. The structure and excitation are described in the INPUT file and the output is written to OUTPUT.


Due to the age of the program, it expects input in the form of punched cards fed into a hopper. It currently does not accept any options.

If OUTPUT is omitted, output is written to stdout and if INPUT and OUTPUT are omitted then the input is taken from stdin and the output written to stdout.

The maximum size of problem which the code can handle must be hard coded at compile time and no dynamic memory allocation is performed. Two versions are therefore provided suitable for different sizes of problem, nec2 is compiled for a maximum of 10000 wire segments and 5000 surface patches, while nec2small is compiled for a maximum of 600 wire segments and 200 surface patches.


nec2 has been superseded by nec4, but this revised code has not been made available to the public, so it is possible that some bugs remain in this version.

Also note that many variant source codes exist based on the original FORTRAN-IV listing in the report. This one is believed to be correctly working, but may still contain extra errors.


This manual page was written by <[email protected]>. The program was developed by G. J. Burke and A. J. Poggio of the Laurence Livermore Laboratory.