Wavelet-modified fringe-adjusted joint transform correlator
| Autor: | Alpana Bhagatji, Arun K. Gupta, Naveen K. Nishchal, B. P. Tyagi |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Computer science
Gaussian ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION symbols.namesake Speckle pattern Wavelet Optics Computer vision Differential (infinitesimal) Electrical and Electronic Engineering Mathematics business.industry Autocorrelation Spectral density Wavelet transform Speckle noise Function (mathematics) Filter (signal processing) Atomic and Molecular Physics and Optics Electronic Optical and Magnetic Materials symbols Artificial intelligence Joint (audio engineering) Focus (optics) business Algorithm |
| Zdroj: | Optics & Laser Technology. 40:99-112 |
| ISSN: | 0030-3992 |
| Popis: | In this paper, we implement a wavelet-modified fringe-adjusted joint transform correlator (JTC) for real-time target recognition applications. In real-time situation the input scene is captured using a charge-coupled device (CCD) camera. The obtained joint power spectrum is multiplied by a pre-synthesized fringe-adjusted filter and the resultant function is processed with an appropriately scaled wavelet filter. Three performance measure parameters: correlation peak intensity, peak-to-sidelobe ratio, and signal-to-clutter ratio have been calculated for fringe-adjusted joint transform correlator (FJTC) and wavelet-modified fringe-adjusted joint transform correlator (WFJTC). The WFJTC has been found to yield better results in comparison to conventional FJTC. To suppress the undesired strong dc, the resultant function is differentiated. Differential processing wavelet-modified fringe-adjusted joint power spectrum removes the zero-order spectra and hence improves the detection efficiency. To focus the correlation terms in different planes in order to capture one of the desired autocorrelation peaks and discard the strong dc and another autocorrelation peak, chirp-encoding technique has also been applied. Targets with Gaussian and speckle noise have also been used to check the correlation outputs. Computer simulation and experimental results are presented. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect