Citation
Abstract
The authors have discovered a computationally fast algorithm for approximating the amplitude A= </ I? + Q? of a quadrature pair (I,Q); specifically, the piecewise linear formula where X = max(\ll, |O\), Y = min(\|, |Q\|). Assuming a uniformly distributed quadrature pair phase angle, the maximum approximation error is 0.028A, the mean error is 0.000066A, and the standard deviation about A is 0.00828A. This algorithm is far more accurate than modified versions of Robertson’s approximation (A= X+bY, b= 1/2 or 3/8 or 1/4) currently being used for most digital signal processing applications. An immediate application is the wideband digital spectrum analyzer under development for monitoring radio frequency interference (RFI) at DSN stations. The algorithm could also be used in digital radar processors.
Details
- Volume
- 42-40
- Published
- August 15, 1977
- Pages
- 97–101
- File Size
- 283.0 KB