Technical Papers and Algorithm Software
This is a list of papers and descriptions of the non-standard algorithms used in this library. These are fairly standard techniques, or modifications of techniques, amenable to real-time processing tasks.
Radar/Sonar Signal Processing Papers and Software
—Space-Time Adaptive Algorithms (STAP)
Note: There is a minor though fatal mistake in the math in "Algorithm 3: FAPI Algorithm" in Belkacemi et all. The Z-Matrix needs to be conjugated in H-Tilde Equation. The Badeau paper implementation of the FAPI algorithm is correct and has been successfully implemented in software.
The FAPI algorithm is presented with more rigor in this paper.
—FIR Filter Design Algorithms
These papers essentially refer to the same algorithm. The code for this filter design technique in included with most of the software downloads as module LS_FIR_Filter {.h,.cpp}.
During the conversion of the MATLAB code to C++, an error was made in converting the indices from MATLAB's 1-based to the C++ 0-based numbering. Change 'n' to '(n-1)' in equation (13). Note, label (13) was mistakenly omitted.
During the conversion of the MATLAB code to C++, an error was made in converting the indices from MATLAB's 1-based to the C++ 0-based numbering. Change 'n' to '(n-1)' in equations (30), (33), (37), (39), (41), and (43).
C++ Software for these Filter Synthesis Algorithms
—Blake Charts and Associated Information
Detailed radar-range equation calculation and background material.
—Radar Blade-Flash Phenomenon
This paper addresses a radar phenomenon where one of the blades of an aircraft rotor is illuminated, at just the right instant, so that a strong (radar) echo is returned directly back to the radar. This strong return is observed with an obviously erroneous Doppler velocity as this is based primarily on the rotation rate of the blade, it's blade-twist and the radar-target geometry. As micro-light aircraft have blades larger in proportion to their body size, this effect should be accentuated and the target more difficult to track. From news stories about UAV attacks on oil installations, this appears to be reality. Blade-flash events tend to be rare, about 1-out-of-1000 scans or so, and are more common at higher radar carrier frequencies. The radar-target geometry indicates blade-flash events should be more probable at close range. As a work-around for purposes of tracking in actual radar systems, the Doppler return is usually just ignored if the received value is obviously incorrect . The range-split information does appear valid in real systems. These casual observations come from experience with operational radar systems, their software, and the data collected from them.