Ionospheric propagation effects can have significant impact on the signal properties of Synthetic Aperture Radar (SAR) systems and they increase with decreasing carrier frequency. Recently, theoretical analyzes of ionospheric distortions in low-frequency SAR signals have indicated a multitude effects that are likely to affect the quality of SAR, interferometric SAR (InSAR), and polarimetric SAR...

Systemic acquired resistance (SAR) is a plant immune response induced after a local infection by necrotizing pathogens. The Arabidopsis NPR1 gene is a positive regulator of SAR, essential for transducing the SAR signal salicylic acid (SA). Mutations in the NPR1 gene abolish the SA-induced expression of pathogenesis-related (PR) genes and resistance to pathogens. To identify additional regulator...

This paper presents a simple yet very effective timedomain sparse representation and the associated sparse recovery techniques that can robustly capture raw ultra-wideband (UWB) synthetic aperture radar (SAR) records. Unlike previous approaches in compressed sensing for SAR, we take advantage of the sparsity and the correlation directly in the raw received pulses before even attempting image fo...

The authors attempted to estimate rice-planted areas using multi-temporal RADARSAT fine-mode and ERS1/SAR data in an early period of rice-planting season. The eastern part of Hiroshima City, HigashiHiroshima City, was selected as the test field, and three multi-temporal RADARSAT fine-mode images and ERS-1/SAR images, taken before and after rice-planting were used as the test data. From the firs...

This paper focuses on Design and Implementation of 10 Bit, 2MS/s successive approximation Register (SAR) Analog to digital converter (ADC) using Split DAC architecture. This SAR ADC architecture is designed and simulated using GPDK 0.18um CMOS technology. It consists of different blocks like sample and hold, comparator, Successive Approximation Register (SAR) and Split Digital to analog convert...

SAR sensors are able to operate under nearly all weather conditions, at daylight or in the night. This is especially beneficial for event-driven applications, like time-critical change-detection for disaster management. Unfortunately, SAR systems suffer from occlusions and ambiguities, especially in urban areas. Additionally, due to layover and foreshortening effects, the geo-referencing of SAR...

This paper introduces a new and novel radar interferometry based on Doppler synthetic aperture radar (Doppler-SAR) paradigm. Conventional SAR interferometry relies on wideband transmitted waveforms to obtain high range resolution. Topography of a surface is directly related to the range difference between two antennas configured at different positions. Doppler-SAR is a novel imaging modality th...

a r t i c l e i n f o a b s t r a c t Synthetic Aperture Radar (SAR) provides high resolution images of terrain and target reflectivity. SAR systems are indispensable in many remote sensing applications. Phase errors due to uncompensated platform motion degrade resolution in reconstructed images. A multitude of autofocusing techniques has been proposed to estimate and correct phase errors in SA...

By acquiring information over a wide area regardless of weather conditions and solar illumination, space-borne Synthetic Aperture Radar (SAR) has the potential to be a promising application for traffic monitoring. However, the backscatter character of a vehicle in a SAR image is unstable and varies with image parameters, such as aspect and incidence angle. To investigate vehicle detectability i...

Local leaf infections by a necrogenic pathogen can lead to systemic acquired resistance (SAR) in untreated leaves. We reasoned that, whatever the nature of the long-distance signal, if it is transported in the phloem, the pattern of SAR induced within the plant by treatment of a single leaf should match the pattern of translocation out of that leaf. The source-sink relationships (orthostichies)...