Portable Near-Field Antenna Scanner

A highly innovative, but, nevertheless, low risk, near field measurement system approach is proposed which will cost = $50K for a truly portable system, including the probe position-scanning apparatus (for small to medium sized antennas). The approach uses extremely light-weight probes and cables to allow a corresponding reduction in probe positioning apparatus size and weight. The heavy and expensive microwave receiver is replaced by a much-smaller, lighter-weight, and less-expensive, broadband heterodyne system. The probes are non- perturbing, eliminating mutual coupling - the principal drawback to more widespread use of the near-field method. For this and other reasons, both high accuracy and speed are anticipated. Without change of probe or other components, the system will cover a broad frequency range (e.g., 50 - 1000 MHz or 1 - 18 GHz) and can be used equally well with 0-dBm sources or with high-power transmitters (with safety). The approach is low-risk because it simply combines principles already proven by the proposers. A complete system (with rudimentary position scanning) will be demonstrated in the laboratory during Phase I. An option to develop a non-perturbing radiating-probe capability to complement the primary, receiving-probe approach is also proposed.