关键词：雷达；天线阵列；光束控制；高功率；低频率
摘 要：Foliage Penetration (FOPEN) radars are critical for detecting and identifying targets concealed by trees and forests. Typically, FOPEN transmits at high powers, making them difficult to design and operate at low frequencies where mismatches are possible. Low operating frequencies also result in large apertures that limit FOPEN systems to large platforms. Novel metamaterials have the potential to reduce the size of FOPEN antennas, but two persistent challenges remain. First, high transmit power requires a low-loss metamaterial solution. Second, the wide bandwidth required by FOPEN systems makes resonant metamaterials solutions unworkable. To shrink the volume of state-of-the-art FOPEN antennas and create a new capability for volume-limited aircraft, Lockheed Martin (LM) Corporation, in conjunction with the Ohio State University (OSU), proposes to develop a novel, metamaterial FOPEN antenna. Shadow Harvest, currently a USAF/ACC JCTD, is a sensor pod and roll-on/roll-off analyst module that adds ISR capability to any C-130 in the USAF fleet within 24 hours.