Mahesh Banavar | Clarkson University (original) (raw)

Papers by Mahesh Banavar

This paper describes the development of an energy-efficient amplify-and-forward distributed estim... more This paper describes the development of an energy-efficient amplify-and-forward distributed estimation scheme using realistic amplifier models. Specifically, a novel algorithm is presented that enables distributed estimation in the presence of amplifier compression resulting from the energy-efficient but non-linear class AB operation. In this system, a digital predistortion scheme is utilized to fit the amplifier at each sensor to a mathematically tractable, soft compression function that roughly mimics the compression region of the amplifier. It is shown both analytically and via simulation that using this scheme has two benefits over linear amplifier operation: improved transmitter efficiency by operating the amplifier in compression, and reduced sensitivity to heavy-tailed distributions due to the soft saturation.

IEEE Transactions on Circuits and Systems – I, vol. 61, no. 1, pp. 302-311, January 2014.

A distributed estimation problem is considered with multiple-access channels between sensors and ... more A distributed estimation problem is considered with multiple-access channels between sensors and a fusion center. The sensors phase-modulate their noisy observations before transmitting them to the fusion center, where a signal parameter is estimated. The asymptotic efficiency of this estimator is then determined by using two inequalities that relate the Fisher information and the characteristic function. A necessary and sufficient condition for equality is found for the first time in the literature. The loss in efficiency of the distributed estimation scheme relative to the centralized approach is quantified for different sensing noise distributions. It is shown that this distributed estimation system does not incur an efficiency loss if and only if the sensing noise distribution is Gaussian.

Information Theory, IEEE Transactions on (Volume:57 , Issue: 10 )

ABSTRACT In this paper, a novel wireless sensor network discovery algorithm is presented which es... more ABSTRACT In this paper, a novel wireless sensor network discovery algorithm is presented which estimates the locations of a large number of low powered, randomly distributed sensor nodes. Initially, all nodes are at unknown locations except for a small number which are termed the “anchor” nodes. The remaining nodes are to be located as part of the discovery procedure. As the locations of sensor nodes are estimated, they can be used in the localization of other nodes.

Abstract Handheld devices are increasingly finding more applications in STEM education. In this p... more Abstract Handheld devices are increasingly finding more applications in STEM education. In this paper, we present the design of an interactive signal processing simulation software operating on both the iPhone OS (iOS) and Android platforms. This object-oriented application is called i-JDSP and is conceptually based on the award-winning Java-DSP (J-DSP) simulation environment. The i-JDSP app offers a user-friendly visual programming interface and provides users with a compelling multi-touch programming experience.

Abstract The use of mobile devices and tablets in engineering education has been gaining lot of i... more Abstract The use of mobile devices and tablets in engineering education has been gaining lot of interest, due to its interactive capabilities and its ability to stimulate student interest. On the other hand, this technology can also enable instructors to broaden the scope of their curriculum and increase student participation. In this paper, we describe an interactive application to perform signal processing simulations on iOS devices such as the iPhone and the iPad.

Abstract A distributed estimation problem using sensor networks is considered. A parameter is obs... more Abstract A distributed estimation problem using sensor networks is considered. A parameter is observed in noise by sensors, phase-modulated using complex exponentials and transmitted over a Gaussian multiple-access channel to a fusion center. The received signal is used to estimate the parameter under observation. The system is evaluated using the asymptotic variance of the estimate.

ABSTRACT Distributed inference has applications in fields as varied as source localization, evalu... more ABSTRACT Distributed inference has applications in fields as varied as source localization, evaluation of network quality, and remote monitoring of wildlife habitats. In this dissertation, distributed inference algorithms over multiple-access channels are considered. The performance of these algorithms and the effects of wireless communication channels on the performance are studied. In a first class of problems, distributed inference over fading Gaussian multipleaccess channels with amplify-and-forward is considered.

Abstract—In this paper, the performance of different localiza-tion algorithms are compared in the... more Abstract—In this paper, the performance of different localiza-tion algorithms are compared in the context of the sequential Wireless Sensor Network (WSN) discovery problem. Here, all sensor nodes are at unknown locations except for a very small number of so called anchor nodes at known locations. The locations of nodes are sequentially estimated such that when the location of a given node is found, it may be used to localize others.

Abstract: An overview perspective of sensor systems and signal and information processing algorit... more Abstract: An overview perspective of sensor systems and signal and information processing algorithms is provided. The development of independent and self-contained sensor devices is discussed for use in wireless sensor networks. Distributed inference techniques for detection and estimation at the fusion center are also discussed.

ABSTRACT A method of protein secondary structural classification is proposed. This method uses th... more ABSTRACT A method of protein secondary structural classification is proposed. This method uses the mean of cepstral feature vectors derived from linear prediction of numerically mapped protein sequences. This is done using two different amino acid indexing techniques, ie, the electron-ion interaction pseudopotentials and Oobatake-Ooi indexing. The classifier's performance is evaluated using the resubstitution test, the jackknife test, and the 10-way crossvalidation method.

Abstract: A relationship between the Fisher information and the characteristic function is establ... more Abstract: A relationship between the Fisher information and the characteristic function is established with the help of two inequalities. A necessary and sufficient condition for equality is found. These results are used to determine the asymptotic efficiency of a distributed estimation algorithm that uses constant modulus transmissions over Gaussian multiple access channels. The loss in efficiency of the distributed estimation scheme relative to the centralized approach is quantified for different sensing noise distributions.

Abstract A sensor network is used for distributed SNR estimation. Sensors observe a signal embedd... more Abstract A sensor network is used for distributed SNR estimation. Sensors observe a signal embedded in noise. These observations are phase modulated using a constant-modulus scheme and transmitted over a Gaussian multiple-access channel to a fusion center. At the fusion center, the location parameter and scale parameter are estimated using a minimum-variance estimator as well as computationally simple alternatives.

Proc. Int. Conf. Acoust …, Jan 1, 2008

Asilomar Conference on …, Jan 1, 2007

IEEE Transactions on …, Jan 1, 2010

Synthesis Lectures on …, Jan 1, 2008

Abstract This book provides an introduction to narrowband array signal processing, classical and ... more Abstract This book provides an introduction to narrowband array signal processing, classical and subspace-based direction of arrival (DOA) estimation with an extensive discussion on adaptive direction of arrival algorithms. The book begins with a presentation of the basic theory, equations, and data models of narrowband arrays. It then discusses basic beamforming methods and describes how they relate to DOA estimation. Several of the most common classical and subspace-based direction of arrival methods are discussed. The ...

Arxiv preprint arXiv: …, Jan 1, 2010

Abstract Orthogonal Frequency Division Multiplexing (OFDM) systems are widely used in the standar... more Abstract Orthogonal Frequency Division Multiplexing (OFDM) systems are widely used in the standards for digital audio/video broadcasting, WiFi and WiMax. Being a frequency-domain approach to communications, OFDM has important advantages in dealing with the frequency-selective nature of high data rate wireless communication channels. As the needs for operating with higher data rates become more pressing, OFDM systems have emerged as an effective physical-layer solution. This short monograph is intended as a tutorial ...

Teaching Documents by Mahesh Banavar

The use of mobile devices and tablets in engineering education has been gaining lot of interest, ... more The use of mobile devices and tablets in engineering education has been gaining lot of interest, due to its interactive capabilities and its ability to stimulate student interest. On the other hand, this technology can also enable instructors to broaden the scope of their curriculum and increase student participation. In this paper, we describe an interactive application to perform signal processing simulations on iOS devices such as the iPhone and the iPad. Furthermore, we describe two laboratory exercises to introduce continuous/discrete convolution and filter design. The exercises and the proposed application will be evaluated by students of an undergraduate DSP course at Arizona State University during Fall 2011. Finally, we describe the planned assessment methodology which will enable us to provide prescriptive recommendations for using i-JDSP in DSP courses.

Relevant Book with iPhone Simulations:

• A. Spanias, Digital Signal Processing; An Interactive Approach – 2nd Edition, 403 pages, Textbook with JAVA exercises, ISBN 978-1-4675-9892-7,Lulu Press On-demand Publishers Morrisville, NC, May 2014.
http://www.lulu.com/shop/andreas-spanias/dsp-an-interactive-approach-second-edition/paperback/product-21640001.html

J. Liu, S. Hu, J. J. Thiagarajan, X. Zhang, S. Ranganath, M. K. Banavar, and K. N. Ramamurthy, “Interactive DSP laboratories on mobile phones and tablets,” Proceedings of IEEE ICASSP, 2012.