IEEE Std 1502-2020 pdf download – IEEE Recommended Practice for Radar Cross-Section Test Procedures.
2. Normative references The following referenced documents are indispensable for the application of this document (i.e., they must be understood and used, so each referenced document is cited in text and its relationship to this document is explained). For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments or corrigenda) applies. IEEE Std 145™-2013, IEEE Standard for Definitions of Terms for Antennas. 3, 4 IEEE Std 149™, IEEE Standard Test Procedures for Antennas. IEEE Std 211™-2018, IEEE Standard Definitions of Terms for Radio Wave Propagation. 3. Definitions, acronyms, and abbreviations 3.1 Definitions For the purposes of this document, the following terms and definitions apply. IEEE Std 145-2013, IEEE Std 211-2018, and the IEEE Standards Dictionary Online should be consulted for terms not defined in this clause. 5, 6 radar cross section (RCS): A measure of the reflective strength of a radar target, usually represented by the symbol σ and measured in square meters. RCS is defined as 4π times the ratio of the power per unit solid angle scattered in a specified direction to the power per unit area in a plane wave incident on the scatterer from a specified direction. More precisely, it is the limit of that ratio as the distance from the scatterer to the point where the scattered power is measured approaches infinity. Three cases are distinguished as follows: a) Monostatic or backscatter RCS: The incident and reflected scattering directions are coincident but opposite in sense. b) Forward-scatter RCS: Energy is reflected or scattered in the same direction as the incident wave. c) Bistatic RCS: Energy is reflected or scattered in any direction other than the incident direction or the opposite of the incident direction.
4. Radar cross-section measurement process 4.1 Introduction Radar scattering is typically represented as the RCS of the test object. The term RCS evolved from the basic metric for radar scattering: the ratio of the power scattered from an object in units of power per solid angle (steradians) normalized to the plane-wave illumination in units of power per unit area. The RCS is thus given in units of area (or effective cross-sectional area of the target, hence the name). Note that the RCS of the test object is a property of the test object alone; it is neither a function of the radar system nor the distance between the radar and the test object, as long as the object is in the far field. Because the RCS of a target can have large amplitude variation in frequency and angle, it is expressed in units of decibels with respect to a square meter and is abbreviated as dBsm (sometimes DBSM or dBm 2 ). In terms of this definition, the RCS of a radar target is a scalar ratio of powers. If the effects of polarization and phase are included, the RCS can be characterized by the complex polarimetric scattering (CPS) matrix, which is based on one-half the real part of the complex Poynting vector. The CPS is proportional to a Hadamard product of a 2×2 matrix of the real-valued RCSs corresponding to each of the four combinations of transmit-receive polarizations and a 2×2 matrix of the complex exponentials associated with the phases of the scattered fields for the same combinations of both polarizations (Bhattacharyya, Sengupta [B6], Ruck [B64]).