The Phase I technical objective is to design a small "virtual" receiving antenna which will operate in the HF, VHF, and UHF frequency ranges (approximately 1 MHz to 1500 MHz) and then to build and test a laboratory prototype. The virtual antenna will be capable of duplicating electrically, but not physically, the wide variety of antennas necessary to receive HF, VHF, and UHF signals. The virtual antenna is extremely low profile, lightweight, and man-packable. Conventional antenna design approaches have constraints which can result in physically large structures, especially at HF frequencies. Tradeoffs between size and electrical performance are required to develop small antennas. Analysis of the most prevalent RF environment in the frequency bands of interest will be necessary to allow optimizing the antenna size and performance tradeoff. Various factors related to the RF environment are analyzed with respect to duplicating as many antenna capabilities as possible in a single package. Delfin Systems has extensive experience in the design and simulation of small portable antennas, as well as communication system analysis and design. Many of Delfin Systems' products use optimized small, lightweight antennas, and ultra low power receivers. Delfin Systems is unique in that it has developed significant expertise in the smooth transition from computer modeling of antenna designs to successful implementation in hardware. The antenna developed in this work is universal, and is capable of working with all common existing equipment; modification of existing equipment is not required. The proposed antenna offers the best tradeoff between physical constraints and desirable electrical properties, and its use or inclusion in existing systems or operational scenarios, requires a minimum of effort and retraining of the user. The virtual antenna offers appreciable advantages over existing antenna schemes.
