"Automated Angular Received-Power Characterization of Embedded mmWave Transmitters Using Geometry-Calibrated Spatial Sampling"

"This paper presents an automated measurement methodology for angular received-power characterization of embedded millimeter-wave (mmWave) transmitters using geometry-calibrated spatial sampling. Characterization of integrated mmWave transmitters remains challenging due to limited angular coverage and alignment variability in conventional probe-station techniques, as well as the impracticality of anechoic-chamber testing for platform-mounted active modules. To address these challenges, we introduce RAPTAR, an autonomous measurement system for angular received-power acquisition under realistic installation constraints. A collaborative robot executes geometry-calibrated, collision-aware hemispherical trajectories while carrying a calibrated receive probe, enabling controlled and repeatable spatial positioning around a fixed device under test. A spectrum-analyzer-based receiver chain acquires amplitude-only received power as a function of angle and distance following quasi-static pose stabilization. The proposed framework enables repeatable angular received-power mapping and power-domain comparison against idealized free-space references derived from full-wave simulation. Experimental results for a 60-GHz radar module demonstrate a mean absolute received-power error below 2 dB relative to simulation-derived references and a 36.5 % reduction in error compared to manual probe-station measurements, attributed primarily to reduced alignment variability and consistent spatial sampling. Unlike classical antenna metrology, the proposed approach does not rely on coherent field acquisition, probe correction, or near-\/far-field transformations, and instead targets geometry-consistent power-domain characterization of installed active mmWave modules. The methodology is readily applicable to embedded radar systems integrated into vehicles, aerial platforms, and robotic structures\u2014such as automotive bumpers or unmanned aerial vehicles\u2014without loss of generality, providing a practical and portable solution for angular validation when conventional turntables and anechoic facilities are impractical or infeasible."