OBJECTIVE To identify search and rescue (SAR) trends in US National Park Service (NPS) units. METHODS A retrospective review of the US National Park Service Annual Search and Rescue Reports from 1992 to 2007 and the SAR statistics for all NPS units in 2005. RESULTS From 1992 to 2007 there were 78,488 individuals involved in 65,439 SAR incidents. These incidents ended with 2659 fatalities, 2...

Recently, Polarimetric SAR (PolSAR) techniques have been much studied as hot research topics in the area of SAR. The objective of this paper is to assess the Principal component analysis (PCA) technique combining with multi-polarimetric SAR data for change detection. PCA proposed in this paper give an effective and quick way to achieve the difference map from the whole multi-temporal images, an...

For multi-channel SAR system, since the minimum antenna area constraint is eliminated, wide swath and high resolution SAR image can be achieved. However, compared to mono-channel SAR system, there exist many deleterious factors in multi-channel SAR system which significantly degrade the quality of SAR image. In this paper, all the deleterious factors in the system are analyzed and classified ac...

In the recent past, airborne Synthetic Aperture Radar (SAR) remote sensing has witnessed several principal and technical improvements. In particular, spatial resolution has been increased significantly, polarimetric SAR, polarimetric interferometric SAR, and tomographic SAR were introduced, and repeat-pass interferometric SAR was developed for airborne SAR sensors. These advances have made poss...

Processing techniques used for analyzing synthetic aperture radar (SAR) data have recently become more complicated, as new SAR sensors have included a variety of sensing functions. Understanding the SAR processing technique is necessary to develop a new approach employing SAR data. This paper presents a concept, a system structure, and an implementation method for an educational SAR processor (...

The management of local and global power deposition in human subjects (specific absorption rate, SAR) is a fundamental constraint to the application of parallel transmission (pTx) systems. Even though the pTx and single channel have to meet the same SAR requirements, the complex behavior of the spatial distribution of local SAR for transmission arrays poses problems that are not encountered in ...