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This paper investigates the abnormal phenomenon of local blackening of the internal circuit substrate caused by low-pressure discharge in the thermal vacuum test of an L-band high-power pulsed solid-state power amplifier for satellite use, i.e., the residual flux inside the product volatilizes under vacuum conditions. Thus, the low-pressure discharge causes a rise in local temperature, and under high local temperature, the silicone rubber is thermally decomposed. There are four proposed engineering improvements, which are proved to be feasible and effective through simulation and re-test verification. The blackening problem's observation, analysis, and resolution are crucial to improve the reliability of high-power microwave solid-state power amplifiers used in spacecraft in high orbit. • Investigates the abnormal phenomenon of local blackening of the SSPA internal circuit substrate, and conduct multipactor research for different underlying factors. • To verify the conjecture of field strength distribution, the method of multi-physics co-simulation was used to determine the fault location and cause, then reproduce the problem scene. • Several effective improvement measures are proposed, and the reliability problem of SSPA is finally solved through simulation and experimental verification. [ABSTRACT FROM AUTHOR]

Abstract: The potentiality of multichannel SAR to provide wide swath and high resolution at the same time has been described in many papers in the last past years. The scope of this paper is to address some of the architectural and technological aspects related to the implementation of a multichannel receiver for a multibeam SAR, with the objective to provide some solutions for different configurations with increased complexity. A further point is the exploitation of the multichannel configuration for the implementation of very high resolution modes. [Copyright &y& Elsevier]

Abstract: Remote sensing in China began in the 1970s, and has undergone several distinct periods of its history from the initial introduction, the early experimentation, to the present innovative development phase. This paper presents an overview of significant achievements in the effort of building the national Earth observing system in China, which includes spaceborne and airborne Earth observing systems, and remote sensing ground satellite receiving station networks. By far, the system has played an important role in many application fields. [Copyright &y& Elsevier]

During the course of years, various activities have been carried out at CESI (incorporating now former CISE Innovative Technologies labs) on Doppler wind lidar (DWL) for spaceborne applications. Historically, the first activities were related to the development of a CO2 laser transmitter for the DWL development with coherent (heterodyne) detection technique. More recently, efforts have been directed to the technology of neodymium solid-state laser transmitter with direct detection (edge technique). Presently, a work in course involves a team of European firms including CESI and is devoted to the breadboarding of a diode-pumped UV laser for DWL application. [Copyright &y& Elsevier]

Archaeological and cultural heritage (ACH), one of the core carriers of cultural diversity on our planet, has a direct bearing on the sustainable development of mankind. Documenting and protecting ACH is the common responsibility and duty of all humanity. It is governed by UNESCO along with the scientific communities that foster and encourage the use of advanced non-invasive techniques and methods for promoting scientific research into ACH and conservation of ACH sites. The use of remote sensing, a non-destructive tool, is increasingly popular by specialists around the world as it allows fast prospecting and mapping at multiple scales, rapid analysis of multisource datasets, and dynamic monitoring of ACH sites and their surrounding environments. The cost of using remote sensing is lower or even zero in practical applications. In this review, in order to discuss the advantages of airborne and spaceborne remote sensing (ASRS), the principles that make passive (photography, multispectral and hyperspectral) and active (synthetic aperture radar (SAR) and light detection and ranging radar (LiDAR)) imaging techniques suitable for ACH applications are first summarized and pointed out; a review of ASRS and the methodologies used over the past century is then presented together with relevant highlights from well-known research projects. Selected case studies from Mediterranean regions to East Asia illustrate how ASRS can be used effectively to investigate and understand archaeological features at multiple -scales and to monitor and assess the conservation status of cultural heritage sites in the context of sustainable development. An in-depth discussion on the limitations of ASRS and associated remaining challenges is presented along with conclusions and a look at future trends. Unlabelled Image • A review of ACH applications in past 110 years of ASRS is performed. • Different ASRS techniques used for ACH application presented, including photography, spectral imaging, SAR and LiDAR. • Ground-truthing is the key to ASRS in ACH applications. • We finally point out the research trends that require further efforts. [ABSTRACT FROM AUTHOR]