Preliminary electromagnetic measurement results from trident Warrior'13 using sources of opportunity

摘要

Trident Warrior 2013 was conducted off the coast of Norfolk, VA from July 12–18, 2013. Passive RF measurements were made between 80–700 Hz using a vertically polarized monopole and a horizontally polarized bicone antennas that are mounted on the R/V Knorr. The RF measurements are composed of three phases: 1. Estimation of unknown source parameters from ship measurements next to the shore as a function of relative azimuth. These include the source power, antenna pattern, and losses. 2. Antenna patterns of receiving antennas attached to the ship are measured by spinning the ship around its axis and averaging the results of multiple turns. 3. One-way RF signal for multiple sources of opportunity are continuously recorded as the ship moves off shore and returns. After the parameters in (1) and (2) are calculated, it is possible to statistically estimate the propagation effects of the ducting environment. The sources of opportunity are composed of numerous FM, TV, Automatic Terminal Information Service (ATIS), VHF omnidirectional radio range (VOR), and Tactical Air Navigation System (TACAN).