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Susmita Das

Bio: Susmita Das is an academic researcher from National Institute of Technology, Rourkela. The author has contributed to research in topics: Bit error rate & Cognitive radio. The author has an hindex of 15, co-authored 126 publications receiving 885 citations.


Papers
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Journal ArticleDOI
TL;DR: Qualitative and quantitative study and analysis indicate that the proposed technique can be used as an effective tool for denoising of ECG signals and hence can serve for better diagnostic in computer-based automated medical system.

144 citations

Journal ArticleDOI
TL;DR: Channel state information for both single-input single-output (SISO) and MIMO systems based on pilot aided arrangement is investigated and MMSE estimation has been shown to perform much better than LS but is more complex than LS for the MIMo system using pilot carriers.
Abstract: A multiple-input multiple-output (MIMO) communication system combined with the orthogonal frequency division multiplexing (OFDM) modulation technique can achieve reliable high data rate transmission over broadband wireless channels. Channel state information for both single-input single-output (SISO) and MIMO systems based on pilot aided arrangement is investigated in this paper. The estimation of channel at pilot frequencies with conventional Least Square (LS) and Minimum Mean Square (MMSE) estimation algorithms is carried out through Matlab simulation. The performance of MIMO OFDM and SISO OFDM are evaluated on the basis of Bit Error Rate (BER) and Mean Square Error (MSE) level. Further enhancement of performance can be achieved through maximum diversity Space Time Block Coding (STBC) and Maximum Likelihood Detection at transmission and reception ends respectively. MMSE estimation has been shown to perform much better than LS but is more complex than LS for the MIMO system using pilot carriers.

62 citations

Proceedings ArticleDOI
01 Nov 2008
TL;DR: This research work provides description, comparative analysis and utility of various reference signal based algorithms as well as blind adaptive algorithms for smart antenna and exhaustive simulation study of beam patterns and learning characteristics have proved the efficacies of the proposed work from application point of view.
Abstract: Smart antenna is recognized as promising technologies for higher user capacity in 3G wireless networks by effectively reducing multipath and co-channel interference. Advent of powerful, low-cost, digital processing components and the development of software-based techniques has made smart antenna systems a practical reality for both base station and mobile station of a cellular communications systems in the next generation. The core of smart antenna is the selection of smart algorithms in adaptive array. Using beam forming algorithms the weight of antenna arrays can be adjusted to form certain amount of adaptive beam to track corresponding users automatically and at the same time to minimize interference arising from other users by introducing nulls in their directions. Thus interferences can be suppressed and the desired signals can be extracted. This research work provides description, comparative analysis and utility of various reference signal based algorithms as well as blind adaptive algorithms. Exhaustive simulation study of beam patterns and learning characteristics have proved the efficacies of the proposed work from application point of view.

56 citations

Journal ArticleDOI
TL;DR: A wavelet-based multiresolution approach along with Shannon energy envelope estimator is utilized to eliminate the noises in ECG signal and enhance the QRS complexes, and a Hilbert transform based peak finding logic is used to detect the R -peaks without employing any amplitude threshold.

55 citations

Journal ArticleDOI
TL;DR: This paper studies the various spectrum occupancy models used in diverse locations by research campaigns worldwide and evaluates up to what percentage the whole spectrum band is occupied by different services.
Abstract: In order to support the ever growing demand of wireless communication systems and wireless local area network based 802.11 devices, the regulators are developing techniques to overcome the permanent scarcity of radio resources. Spectrum sensing in cognitive radio (CR) is considered as a key technology which estimates the availability of the licensed spectrum band for additional usages. The underutilized licensed band can be exploited among the secondary users provided that they would not cause any interference to the primary user. So, evaluation of spectrum occupancy is the main approach towards the successful deployment of CR. This paper studies the various spectrum occupancy models used in diverse locations by research campaigns worldwide. The detail analyses of the empirical results in different scenarios of measurement have been compared. The purpose of this survey is to evaluate up to what percentage the whole spectrum band is occupied by different services.

32 citations


Cited by
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01 Jan 2016
TL;DR: The linear and nonlinear programming is universally compatible with any devices to read and is available in the book collection an online access to it is set as public so you can download it instantly.
Abstract: Thank you for downloading linear and nonlinear programming. As you may know, people have search numerous times for their favorite novels like this linear and nonlinear programming, but end up in malicious downloads. Rather than reading a good book with a cup of tea in the afternoon, instead they juggled with some infectious bugs inside their desktop computer. linear and nonlinear programming is available in our book collection an online access to it is set as public so you can download it instantly. Our digital library spans in multiple locations, allowing you to get the most less latency time to download any of our books like this one. Kindly say, the linear and nonlinear programming is universally compatible with any devices to read.

943 citations

Book
01 Jan 1994

607 citations