| The development of computer programs for modeling antennas began in the 1960s when main-frame computers were making advancements. Modeling codes that could run on desktop computers made their appearance in the early 1980s. The design of directional antenna arrays for medium-frequency (MF) broadcasting stations has a much longer history, however, reaching back to the mid-1930s when computations were done using a slide rule.
In the early years, methods involving approximations (such as the assumption of sinusoidal current distributions on the radiators) were developed and broadcasters have used them with reasonable success up to the present day. For the most part, however, to do that work the broadcaster’s use of the computer has been relegated primarily to arithmetical operations rather than to actual modeling of the antenna. The success of simple design methods, and the fact that the generalpurpose modeling codes and broadcast antenna engineers sometimes seem to “speak a different language,” may account for the somewhat slow adoption of computer modeling by the broadcast community. |
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