VLF/LF coupler and antenna modeling

An extremely versatile low-cost design tool has been developed to aid in the analyses of VLF/LF coupler and antenna systems. This tool is a computer program that is capable of simulating the performance of a wide range of transmitting wire antennas. The principle features of the program are (1) integration of a lumped constant network (coupler) with a distributed element (antenna); (2) incorporation of automatic tuning and coupling control; and (3) integration of time-domain and frequency-domain analyses with FSK (frequency shift keying) and MSK (minimum shift keying) modulation. A matched filter detector measures modulation loss due to bandlimiting and computes the effective antenna power.<>