Ms. Nilima Rani Chaube
Nilima Rani Chaube (Member, 2013) received B.Sc. degree from Bundelkhand University, Jhansi in 1988, M.Sc. (Electronics) Degree from Dayalbagh Educational Institute, Agra in 1990 and M. Tech. (Microwave Electronics) from University of Delhi in 1992.
She joined Institute for Plasma Research (IPR), Gandhinahar in year 1993 and was responsible for the design and development of multi-channel Superheterodyne Radiometer (60-75 GHz) for Electron Cyclotron Emission diagnostic of Aditya tokamak Plasma. She joined Space Applications Centre in 1999 and developed algorithms for data products generation of Active (Scatterometer Oceansat-2, RISAT-1) and Passive (Multi Scanning Microwave Radiometer (MSMR) Oceansat-1) microwave sensors.
She has developed various image formation algorithms using Simulator-Processor-Evaluator approach for various imaging modes of SAR. SAR Simulator is designed to generate raw data in Stripmap, ScanSAR and Spotlight modes for a given orbit and geolocation of point target. She has developed various algorithms Range Doppler and Chirp Scaling algorithms for Stripmap mode, Short Inverse Fast Fourier Transform algorithm for burst mode like Alternate polarization, modified Specan algorithm for ScanSAR mode and variable fm rate sub-aperture algorithm for sliding Spotlight mode for SAR processor. Evaluator is developed to certify the performance of Processor by evaluating geometric and radiometric characteristics (3dB resolution, PSLR, ISLR) of point targets. All algorithms are validated at various look angles frequencies (L, C & X band) using ERS1, RADARSAT1 & DLR-ESAR raw data and are used for generating RISAT-1 data products. She has also developed SAR Geolocation algorithm for geocoding of SAR SLC & ML images. She has analysed effectiveness of RISAT-1 onboard Block Adaptive Quantization (BAQ) by implementing BAQ on DLR-ESAR raw data. She has also provided simulated RISAT raw data for testing hardware of near real time processor. She has evaluated quality of DMSAR and TECSAR raw data and data products. She has analysed RISAT-2 Stripmap & Spotlight mode raw data & data products to ascertain in orbit radiometric & geometric performance, geo-location accuracy and internal distortion up to cm levels. She has developed algorithms for Altimeter data processing and supported ground segment activity of SARAL AltiKa data products. She has simulated Altimeter waveform over ocean region and developed Maximum Likelihood Estimator for retrieval of significant wave height, off nadir pointing and back scattering coefficient. She has also developed Raw data Processor (for converting raw data count to backscatter coefficient) based on Specan algorithm for Scatterometer onboard Oceansat-2. She has also analysed Optical (MX & HySI payloads, IMS-1) data. She has designed and implemented algorithm in FPGA Xilinx Virtex Series for high precision (16 bit) analog to digital conversion for MM-wave sounders. Currently she is principal investigator of SARAL-utilization programme for characterization of land cover using SARAL-AltiKa data.
She has been on deputation to IAI/ELTA Israel and CNES France. She has authored/co-authored 74 technical documents with 4 national and 6 international publications. She is recipient of Astronautical Society of India (ASI) Space Gold Medal award for year 2008 for her meritorious contribution to ISRO programmes. She is life member of Indian Society of Remote Sensing.