Lightweight erectable space antennas

The requirements for large leightweight antennas for various space applications has led to the investigation of many types of self-erecting space antennas. The techniques for achieving erectable antennas are discussed, along with the possibilities and problems that each presents to the antenna engineer. Some erectable antenna types, including several which have been built at Goodyear Aircraft Corporation, are described. These include an inflatable turnstile, mechanically erected parabolics, an inflatable lenticular, an inflatable airmat paraboloid and a foamed reflector. An example of the type of problem to be discussed includes the tradeoff between the structural aspects and the electrical design of the lenticular antenna, which uses fabric drop threads in its interior and therefore requires some attention to the dielectric constant of the medium to achieve equivalent electrical path lengths.