Coplanar waveguide microwave loop filter

✍ Scribed by L. C. Koh; S. Uysal

• Book ID: 101272194
• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 127 KB
• Volume: 16
• Category: Article
• ISSN: 0895-2477
• DOI: 10.1002/(sici)1098-2760(199709)16:1<4::aid-mop2>3.0.co;2-h

✦ Synopsis

4. Conclusions

A technique to improve the quality of radar images was demonstrated using simulated and measured radar data. Instead of applying second-order statistics to radar imaging, fourth-order statistics were used. The result is a greater dynamic range for conventional images using the Fourier Ž . transform. For subspace-based methods MUSIC , the separation between signal and noise subspace results in a larger step in the eigenvalues. The decision on the number of signal eigenvalues to use for imaging can be made more accurately. This will reduce the effect of spurious peaks in the image due to the commonly used principle of choosing a larger signal subspace, and thus including noise eigenvectors in the signal subspace.

The main advantage of the fourth-order images is the fact that small signals with amplitudes in the same range as the noise level can be detected. Using second-order statistics, these signals would have been lost in the noise. This opens a whole new range of applications for radar imaging, especially in environments where the noise level is relatively high and cannot be controlled.