Source Code Description: Subroutine GANT1

GANT1

PURPOSE: to consider the wire structure as a transmitting antenna and calculate the input impedance and current distribution.

METHOD: If a wire antenna is driven by a voltage generator v_i located at one of the current sampling points l_i and if displacement currents are neglected, Ampere's law yields

where F is the sinusoidal expansion function. Thus, the excitation voltages V_m will vanish everywhere except where v_i is not zero.

The DO LOOP ending with statement 50 uses the delta-gap model defined above to determine the excitation voltage CJ(I) for all the dipole modes. These are stored temporarily in CG(I). Then subroutine SQROT is called to obtain a solution of the simultaneous linear eguations. SQROT stores the solution (the loop currents) in CJ(I).

In the DO LOOP ending at statement 80, the complex power input and input impedance(s) are calculated. The time-average power input (PIN) is the real part of the complex power input.

Subroutine RITE is called to make the transformation from the loop currents to the branch currents. If IWR is a positive integer, RITE will write out the list of branch currents.

Finally, GANT1 calculates the radiation efficiency by calling subroutine GDISS to obtain the time-average power dissipated in the lumped loads and the imperfectly conducting wire.

CALLED BY:

• MAIN

CALLS TO:

• GDISS
• RITE
• SQROT