Abstract: A computerized process can design antennas using a completely deductive approach, that is, the desired electromagnetic properties are specified and the wire configuration that most closely produces the optimum result is synthesized. This new process uses a genetic algorithm in conjunction with an electromagnetic code. The genetic algorithm randomly selects a sample set of possible wire configurations from among all possible wire configurations. The performance of each configuration is computed using the electromagnetic code and ranked in order of quality. Partial solutions to this problem are obtained by "mating" the best wire configurations with one another. This evolutionary process is continued until an optimal wire configuration is obtained. Although this new process has only been tested on wire antennas, it can be used to design printed antennas, microstrip antennas, patch antennas and any other type of antenna that can be analyzed using an electromagnetic code.

Abstract: The cylindrical chamber allows one to quickly package a test fixture with attached sample, cool it to liquid-nitrogen temperature in a few minutes, and warm it back up to room temperature in a few minutes in a dry, helium or nitrogen atmosphere, which prevents water or ice from condensing on the test fixture and sample.