Empirical Study of Flight-Dynamic Influences on Radar Cross-Section Models

Abstract

In this work, measurements and a method for analyzing flight-dynamic effects on radar cross-section models for aircraft are presented. Flight-dynamic effects need to be considered when designing combat aircraft and creating target models for radar simulators. The work is based on flight data from three different types of aircraft: Piper PA-28 Archer II, Boeing 737, and Saab JAS 39 Gripen. Using inertial navigation and global-positioning systems, the motions of the three aircraft are recorded in flight. From the data, aspect angles toward a radar station located in the extension of the intended flight path are generated using a simulator. It is found that the major contribution to perturbations in aspect angles is due to the rotational degrees of freedom and that bivariate normal distributions are a good candidate for approximating the uncertainty in aspect angles for all three aircraft types. It is also found that each rotational degree of freedom is close to a normal distribution but that the parameter values of the distribution vary with altitude and aircraft type. NomenclatureAz = azimuth aspect angle, deg a = major axis of confidence ellipse, deg b = minor axis of confidence ellipse, deg El = elevation aspect angle, deg E i = incident electric vector field, V∕m E s = scattered electric vector field, V∕m G = antenna gain h r = radar antenna height, m h t = target altitude, m P t = transmitted power, W R = range between radar and target, m R h = range to radar horizon, m R max = maximum detection range, m r e = effective radius of Earth, m S min = minimum detectable signal, W α = alpha risk θ = eigenvalue of Σ λ = radiation wavelength, m σ = radar cross-section, m 2 μ = mean value, deg ρ = correlation coefficient Σ = covariance matrix σ Az = azimuth standard deviation, deg σ El = elevation standard deviation, deg χ 2 2 α = upper αth percentile of chi-squared distribution with two degrees of freedom

Analysis of aerodynamic and stealth characteristics of aircraft under the action of microwave plasma

“…The European Union and Russia have also launched relevant programs and established comprehensive theoretical simulation test pathways. Persson and Bull [6] also proposed a method to measure and analyze the influence of flight dynamics on the radar cross-section model of an aircraft based on flight data from three different types of aircraft: Piper PA-28 Archer II, Boeing 737, and Saab JAS39 Gripen. Papageorgiou et al [7] proposed a Multidisciplinary Design Optimization (MDO) framework for the early design phase of Unmanned Aerial Vehicles (UAVs), focusing primarily on trade-offs between mission, stealth, and surveillance performance requirements for calculating radar cross-section (RCS) and sensor performance.…”