The WI-187-UDR-15E is a laboratory-grade microwave E-Plane Sectoral Horn Antenna professionally engineered by Fei Teng Wireless Technology Co., Ltd. (FT-RF) for specialized radiation pattern shaping, broad-area signal capture, and anechoic calibration routines across the 3.95 GHz to 5.85 GHz C-Band spectrum. By flaring specifically within the vertical E-plane mechanical boundaries, this premium sectoral instrument enforces an asymmetrical illumination profile, delivering an expansive 78° horizontal spatial coverage swath while simultaneously preserving a tightly focused 16° vertical beamwidth aperture matrix. Precision CNC machined from high-grade structural aluminum alloy in Taiwan, the radiator maintains a stable typical directive gain profile of 15 dBi to provide absolute spatial tracking constancy. Featuring an integrated square UDR Flange format for direct, low-loss interconnect mating, this robust 0.9 KG structural component completely eliminates mode breakdown anomalies, rendering it the definitive choice for broad-area tactical monitoring, electronic warfare simulation networks, wide-angle chamber evaluations, and professional laboratory RF deployments where precise spatial parameters are required.