A very efficient electronically tunable helical antenna convering hf band with 2 elements has been postulated. A unique pin diode tuning network allows the design of an antenna that is at least 10 db higher in efficiency than antennas of comparable size and provide USEC switching speeds. Some of the antenna characteristics have been demonstrated in previous work at vhf. The Phase I effort is intended to verify critical characteristics that have not to date been demonstrated. These characteristics include high power operation (e.g. 400 watts cw), network characteristics at hf, coupling between antennas in a co-site configuration, and failure mode analysis. The Phase I effort will include analytical modeling of the antenna plus fabrication of a test configuration that will be tested to demonstrate the above characteristics.
Keywords: Antennas High Power Tuned Electronically Helix Monopole HF
