2019 URSI Asia-Pacific Radio Science Conference (AP-RASC)最新文献

{"title":"Analysis of mobile tower radiation and its health effects in Champhai District of Mizoram","authors":"Lallawmzuala, Lalrinthara Pachuau, Z. Pachuau","doi":"10.23919/URSIAP-RASC.2019.8738408","DOIUrl":"https://doi.org/10.23919/URSIAP-RASC.2019.8738408","url":null,"abstract":"With the significant increase in mobile phone usage,possible health risks related to Rf exposure have become the subject of considerable attention,.This includes effect from exposure to both cell phones and base stations.The aim of the present paper is to study different symptoms of health effects of Rf radiation from mobile tower on nearby inhabitants and those who were not exposed.Health concerns can be divided into two main categories : short term and long term effects.The short term effects include brain electrical activity,cognitive function,sleep, heart rate and blood pressure.However,the long term effects include tinnitus,headache,dizziness,fatique,sensations of warmth,dysesthesia of the scalp,visual symptoms,memory loss and sleep disturbance,muscle problem and epidemiological effects including cancer and brain tumours. A detailed survey was conducted on people living within and beyond 50m from mobile base station, on thirteen (13) different health symptoms faced by inhabitants living near mobile tower in six different localities in Champhai district for the first time since mobile tower was erected in 2005. Power density of RF radiation have also been measured within 50m and outside 50m from the station for GSM900 and GSM1800 in the same locality.The measured power densities have been compared with standard limits given by various scientific bodies like International Commission on Non-Ionizing Radiation Protection (ICNIRP),Bioinitiavive Report 2012 and current Indian National Standards. The radiation level is under permissible limits as per the guidelines adopted in India. Also the results were statistically analysed and compared by using Kruskal Walli’s t-test. It was found that the comparisions are statistically significant with p<0.05 in all the six localities where headache, memory loss and muscle pain are the most common health complaints.Correlation between power density and significant health complaints was studied and it has been observed that there is a strong positive correlation between power density and complaints on nonspecific health symptoms.","PeriodicalId":344386,"journal":{"name":"2019 URSI Asia-Pacific Radio Science Conference (AP-RASC)","volume":"42 27","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133787433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sparse signal detection with spatial diversity using multi-rate sampling","authors":"Esteban Selva, Y. Louët, A. Kountouris","doi":"10.23919/URSIAP-RASC.2019.8738211","DOIUrl":"https://doi.org/10.23919/URSIAP-RASC.2019.8738211","url":null,"abstract":"We propose a spectrum sensing system consisting of K spatially distributed cognitive radios linked to a fusion centre. Each cognitive radio samples a wideband sparse multi-band signal, where each band comes from a distant device, at a random rate below Nyquist. Estimations of the signal support are done locally on undersampled data, then are processed at the data fusion center which finally outputs the support of the original signal. The proposed system is resilient and offers substantial gains in terms of detection by exploiting spatial diversity. The overall sampling rate remains moderate and the local sampling rates are far below that of Nyquist, relaxing the sampling rate constraints on ADCs, a traditional limiting factor in wideband sampling.","PeriodicalId":344386,"journal":{"name":"2019 URSI Asia-Pacific Radio Science Conference (AP-RASC)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121967497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The NISAR Mission – An NASA/ISRO Space Partnership Supporting Global Research and Applications","authors":"P. Rosen, Raj Kumar","doi":"10.23919/URSIAP-RASC.2019.8738639","DOIUrl":"https://doi.org/10.23919/URSIAP-RASC.2019.8738639","url":null,"abstract":"Since the 2007 National Academy of Science “Decadal Survey” report [1], NASA has been studying concepts for a Synthetic Aperture Radar (SAR) mission to determine Earth change in three disciplines – ecosystems, solid earth, and cryospheric sciences. NASA has joined forces with the Indian Space Research Organisation (ISRO) to fulfill these objectives. The NASA-ISRO SAR (NISAR) mission is now in development for a launch readiness in late 2021. The mission’s primary science objectives are codified in a set of science requirements to study Earth land and ice deformation, and ecosystems, globally with 12-day sampling over all land and ice-covered surfaces throughout the mission life. The US and Indian science teams share global science objectives; in addition, India has developed a set of local objectives in agricultural biomass estimation, Himalayan glacier characterization, and coastal ocean measurements in and around India. Both the US and India have identified agricultural and infrastructure monitoring, and disaster response as high priority applications for the mission.","PeriodicalId":344386,"journal":{"name":"2019 URSI Asia-Pacific Radio Science Conference (AP-RASC)","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125529556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reducing the RCS of MIMO Antenna using Angularly Stable FSS","authors":"S. R. Thummaluru, R. Chaudhary","doi":"10.23919/URSIAP-RASC.2019.8738419","DOIUrl":"https://doi.org/10.23919/URSIAP-RASC.2019.8738419","url":null,"abstract":"1.A systematic design procedure for reducing the MIMO antenna RCS has been presented in this paper. The RCS reduction has been achieved at 11.3 GHz, which is out-of-band as compared to antenna working frequency of 2.18 GHz. The design flow starts with developing an isolation enhancement network for MIMO antenna which is not going to disturb the RCS reduction process. Next, an incident-and polarization-angle insensitive frequency selective surface (FSS) is designed and its array is introduced in the place of a conventional ground plane of MIMO antenna. Designed FSS is introduced in such a way that the antenna characteristics and isolation among the antenna ports are preserved by achieving the RCS reduction of an antenna at the bandpass frequency of FSS. The proposed FSS is angularly stable, hence, almost constant RCS reduction has been found for most of the incident angles. The final proposed low RCS MIMO antenna has been fabricated and measured to validate the simulation results.","PeriodicalId":344386,"journal":{"name":"2019 URSI Asia-Pacific Radio Science Conference (AP-RASC)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124627139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of nonlinear interaction of plasma wave using higher order spectrum in whistler frequency range","authors":"Shivali Verma, Harleen. Kaur, A. Gwal","doi":"10.23919/URSIAP-RASC.2019.8738704","DOIUrl":"https://doi.org/10.23919/URSIAP-RASC.2019.8738704","url":null,"abstract":"Various types of wave phenomena in the whistler frequency range have been studied in the ionosphere-magnetosphere system in past, which specify the significance of wave-wave interactions in the space plasma. In our work we shall be paying attention on spectrum broadening processes which can be unified by the parametric (nonlinear) interaction of whistler mode waves with ionosphere and magnetospheres plasma [1]. These effects are enlightening on the basis of whistler wave interactions with small-scale plasma irregularities and quasi-electrostatic lower-hybrid resonance (LHR) waves. This process is analogous to the parametric interaction of high-frequency (HF) radio waves in the ionosphere F-layer near the reflection level [2].An analytical study of nonlinear-mode coupling between the VLF transmitter pulse and natural ELF/VLF emissions during the spectrum broadening by bicoherence analysis has been done by many researchers [3, 4, 5, 6]. Therefore in this attempt we analyses the nonlinear wave-wave interaction in whistler frequency range by wavelet bicoherence analysis. In past the bicoherence analysis computed over the Fourier modes of the VLF signal but due to the non-stationary and non-Gaussian nature of VLF signal, we compute the bicoherence by a better tool termed as wavelet transform. The wavelet bicoherence mathematically define as [7]","PeriodicalId":344386,"journal":{"name":"2019 URSI Asia-Pacific Radio Science Conference (AP-RASC)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117097822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Autonomous data collection for Disaster management: location aspects","authors":"T. Tanzi, M. Chandra","doi":"10.23919/URSIAP-RASC.2019.8738499","DOIUrl":"https://doi.org/10.23919/URSIAP-RASC.2019.8738499","url":null,"abstract":"In Search and Rescue (SaR) operations, Autonomous system dedicated to data collection meant for the rescuers constitute a good way to detect buried people under debris. For example, a Ground Penetrating Radar (GPR) coupled to an autonomous system, constitutes a very efficient tool available for accessing unreachable domains for the rescuers. Such areas are characterised by very hostile conditions. These are dangerous zones due to their instability, and due to the difficulty to move in this environment, for instance: holes, geological breaches, narrow passages, etc. The possibilities to block the autonomous system in the hostile environment and to lose it are very important aspects that need to be addressed.","PeriodicalId":344386,"journal":{"name":"2019 URSI Asia-Pacific Radio Science Conference (AP-RASC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120962540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"All-optical clock recovery from advanced modulation formats through injection-locking of fiber laser","authors":"M. Srivastava, L. V., B. Srinivasan, D. Venkitesh","doi":"10.23919/URSIAP-RASC.2019.8738246","DOIUrl":"https://doi.org/10.23919/URSIAP-RASC.2019.8738246","url":null,"abstract":"The use of advanced modulation formats in optical communication imposes stringent requirements on optical signal to noise ratio (OSNR) and thus, 3R (re-amplification, reshaping and retiming) regeneration is increasingly relevant in long-haul communication links. Clock recovery is a critical functionality for performing the mid-span 3R regeneration and an all-optical implementation is desirable to minimise the number of O-E-O conversions [1]. Injection locking of fiber lasers has proved to be a reliable method that yields improved jitter performance [2]. In this paper, we will explain the working principle of injection locking in an nonlinear polarisation rotation-based passive mode locked laser. We also present the details of clock tone enhancement from non-return-to-zero (NRZ) pulses using a nonlinear SOA. We will further discuss the experimental results of clock recovery for 10 Gbaud NRZ signals, and its resilience to carrier wavelength and modulation formats such as OOK, BPSK, QPSK and 16-QAM.","PeriodicalId":344386,"journal":{"name":"2019 URSI Asia-Pacific Radio Science Conference (AP-RASC)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123400925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review: Wideband Spectrum Sensing for Next Generation Wireless Networks","authors":"H. Joshi, S. Darak","doi":"10.23919/URSIAP-RASC.2019.8738355","DOIUrl":"https://doi.org/10.23919/URSIAP-RASC.2019.8738355","url":null,"abstract":"Next generation wireless networks are expected to operate in licensed, shared as well as unlicensed spectrum. To enable this, central controller or base stations need wide-band spectrum sensing (WSS) to periodically identify potential spectrum resources and allocate them to the desired users. The main challenge in WSS is the requirement of prohibitively high sampling rate analog-to-digital converters (ADC) which are area and power hungry. To overcome this bottleneck, sub-Nyquist sampling based WSS (SNS-WSS) techniques have been discussed in the literature. The SNS-WSS exploits the sparse nature of a wideband spectrum and hence, accomplish WSS using low-rate ADCs. In this paper, we review and compare the advantages and drawbacks of existing SNS-WSS. We also discuss future research directions for making SNS-WSS feasible in next generation wireless networks.","PeriodicalId":344386,"journal":{"name":"2019 URSI Asia-Pacific Radio Science Conference (AP-RASC)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128591209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics of Group III-V Based Multiple Quantum Well Transistor Laser: A simulation based Analysis","authors":"Jaspinder Kaur, R. Basu, A. Sharma","doi":"10.23919/URSIAP-RASC.2019.8738752","DOIUrl":"https://doi.org/10.23919/URSIAP-RASC.2019.8738752","url":null,"abstract":"Simulation based study of InGaAs-GaAs tunnel- injection transistor laser having multiple quantum wells in its base, is presented. We have utilized the luttinger-kohn k.p. model to obtain the various characteristics of multiple quantum well transistor laser including band to band tunneling, free carrier loss, bound state energies, TE gain, TE spontaneous emission rate density etc. Gain and spontaneous emission are calculated by quantum well bound state energies which are obtained through the schrodinger equation. In this paper, simulations are employed to obtain the characteristics of In0.2 Ga0.8 As having multiple quantum wells in its base.","PeriodicalId":344386,"journal":{"name":"2019 URSI Asia-Pacific Radio Science Conference (AP-RASC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130992115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Python Based InSAR Processing Tool For ISRO SAR Missions","authors":"Rajvi Panchal, S. Chirakkal, D. Putrevu, A. Misra","doi":"10.23919/URSIAP-RASC.2019.8738729","DOIUrl":"https://doi.org/10.23919/URSIAP-RASC.2019.8738729","url":null,"abstract":"Interferometric Synthetic Aperture Radar (InSAR) is a remote sensing technique widely used to generate elevation maps, commonly known as interferograms, that depicts surface deformations and topographic trends. Changes in topography and deformations can be measured over span of days to years and are recorded in the form of fringes. Taking into consideration the upcoming NASA-ISRO Synthetic Aperture Radar (NISAR) mission, which is designed to support wide-swath interferometry, it is high time to develop a InSAR processing tool dedicated to ISRO missions. Due to its versatile features, popularity, flexibility and the huge library support, the tool development was chosen to be in Python3 programming language. In this paper the first results obtained from the in-house developed, python 3 based, software tool for InSAR processing are presented. The tool is slated to become part of the Microwave Data Analysis Software (MIDAS) of SAC, which is a generic SAR processing software suite. Currently, the tool accepts ERS 1/2, ENVISAT, RADARSAT-2 and ALOS-2 data. For verification purpose, the outputs generated by the tool are compared with those generated by the freely available Delft Object-oriented Radar Interferometric Software (DORIS) developed by the Delft Institute of Earth Observation and Space Systems (DEOS), Delft University of Technology.","PeriodicalId":344386,"journal":{"name":"2019 URSI Asia-Pacific Radio Science Conference (AP-RASC)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134048717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}