AESA Fundamental Theory

This lecture describes theoretically how beams are electronically scanned and how AESA performance can be modeled analytically with illustrated examples. It begins with the 1D pattern expression for an AESA. This is followed by a detailed description of fundamental AESA performance parameters and their relation to the analytical pattern expression. These parameters include beamwidth, instantaneous bandwidth, grating lobes, error effects including quantization and random amplitude and phase errors, and amplitude weighting for sidelobe control. Building upon this foundation, more complex topics are detailed and derived for conformal arrays and 2D AESAs inclusive of circular apertures and grid type (rectangular and triangular). Different coordinate systems are described including antenna, radar, and antenna cone angle coordinate systems and how to compute the impact of roll, pitch, and yaw on AESA pattern performance.