Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Rajorshee Raha is active.

Publication


Featured researches published by Rajorshee Raha.


ieee international conference on control system computing and engineering | 2014

Synthesis of sampling modes for adaptive control

Rajorshee Raha; Aritra Hazra; Akash Mondal; Soumyajit Dey; P. P. Chakrabarti; Pallab Dasgupta

Recent studies have shown that adaptively regulating the sampling rate results in significant reduction in the computational resources of embedded software based control. Selecting a uniform sampling rate for a control loop is robust, but pessimistic for sharing processors among multiple control loops. Fine-grained regulation of periodicity achieves better resource utilization, but is hard to implement online in a robust way. However, an offline control theoretic analysis of the system illustrates the benefits of proper period selection for different modes. Such analysis reveals the necessity to automatically derive a multi-mode scheduler and converge on suitable periods for each mode. This paper proposes a methodology to automatically generate such a scheduler for an embedded real-time control system leveraging its design attributes. The proposed method provides significant gains in computational efficiency without trading off the performance.


international symposium on intelligent control | 2015

Adaptive sharing of sampling rates among software based controllers

Rajorshee Raha; Soumyajit Dey; Pallab Dasgupta

Recent control theoretic studies have shown that the sharing of electronic control unit (ECU) bandwidth among multiple controllers can be adaptively regulated to achieve better control performance as opposed to static bandwidth allocation to each controller. Unfortunately the ideal controllers cannot always be implemented, since the computational platform does not admit unrestricted choice of sampling periods for the controllers. Therefore the controllers for each combination of the sampling rates must be pre-synthesized. This paper develops an algorithmic basis for identifying the optimal feasible combination of sampling rates at various modes of a system consisting of multiple controllers. The proposed approach is shown to yield controllers that are feasible and having comparable benefits as compared to the ideal controllers.


IEEE Embedded Systems Letters | 2016

Multirate Sampling for Power-Performance Tradeoff in Embedded Control

Rajorshee Raha; Souradeep Dutta; Soumyajit Dey; Pallab Dasgupta

Recent research has emphasized the benefits of adaptively regulating the sampling rate of a plant as a function of its state of operation. In this letter, we study the problem in the context of the wide variety of low power embedded systems, where sampling rate has a direct relationship with power consumption. We propose a methodology for designing multirate controllers that switch between sampling rates depending on the disturbance levels while operating under a given energy budget. Our empirical studies indicate that better control performance can be achieved within the energy budget by adaptive regulation of the sampling rate, thereby demonstrating the efficacy of our proposal.


Ingénierie Des Systèmes D'information | 2013

Speaker Independent Word Recognition Using Cepstral Distance Measurement

Arnab Pramanik; Rajorshee Raha

Speech recognition has been developed from theoretical methods practical systems. Since 90’s people have moved their interests to the difficult task of Large Vocabulary Continuous Speech Recognition (LVCSR) and indeed achieved a great progress. Meanwhile, many well-known research and commercial institutes have established their recognition systems including via Voice system IBM, Whisper system by Microsoft etc. In this paper we have developed a simple and efficient algorithm for the recognition of speech signal for speaker independent isolated word recognition system. We use Mel frequency cepstral coefficients (MFCCs) as features of the recorded speech. A decoding algorithm is proposed for recognizing the target speech computing the cepstral distance of the cepstral coefficients. Simulation experiments were carried using MATLAB here the method produced relatively good (85% word recognition accuracy) results.


wireless and optical communications networks | 2012

De-noising/noise cancellation mechanism for sampled speech/voice signal

Arnab Pramanik; Rajorshee Raha

In any communication system noise always had been a major area of concern. Noise signals affect the transmitted signals during transmission. Every signal that we acquire at the receiver end of any communication system is somehow affected by noise. Noise is the unwanted part of the signal. Signals can be of various types in communication systems depending upon the requirement of the system, like signals carrying information during transmission of voice or speech or image or video. Each of these signals get affected during transmission. So for de-noising of these signals of deferent types we need different noise cancellation mechanism. In this paper we have adopted a noise cancellation mechanism for signals carrying information in voice communication. In voice communication the recorded speech data signal transmitted will be useless until and unless proper noise cancellation mechanism is adopted at the receiver end. There are so many mechanisms for such noise cancellation. A lot of research work is going on to find a complete solution to this problem. In this paper, we have adopted a new adaptive noise cancellation algorithm. This algorithm, we have proposed is based on mean power calculation of the speech signal. The average power of each speech frame is calculated. Then those frames are accepted which exhibits average power above certain threshold level.


international conference on control automation and systems | 2017

Adaptive regulation of sampling rates for power efficient embedded control system design

Rajorshee Raha

In recent times adaptive regulation of sampling rates has gained significant attention in research community and researchers has demonstrated its effectiveness in embedded control applications from different perspectives. In low power embedded control systems, the sampling rate of the control tasks has a direct relationship with control performance and power consumption. In this paper, we investigate the possibility of improving the power efficiency of low power embedded control systems by regulating the sampling rate of the control tasks. On this regard, we present algorithmic approaches for on-line regulation of sampling rates of the control task under some power-performance trade-off. We present elaborative results which demonstrate the efficacy of our proposed approaches.


international conference on system theory, control and computing | 2016

Synthesis of sampling modes of multi-rate systems for guaranteed stability

Rajorshee Raha

Adaptive regulation of sampling period has gained significant attention in research community in recent times and some encouraging techniques has been reported in this research direction. One such promising technique is commonly referred as multi-rate sampling. A linear control system that uses multi-rate sampling contains a collection of sampling periods and appropriately designed controllers for the corresponding sampling modes. Further, the switching between the sampling modes may depend upon some switching guards. In this paper, we address the problem of the multi-rate sampling associated with linear time invariant control systems, by formalizing the basis of selecting the sampling periods for the different sampling modes, such that overall system stability under arbitrary switching can be guaranteed. We also present a framework for controller synthesis in a multi-rate setting, such that our primary goal is achieved. Further, we present a case study using standard academic example and provide results in support of our proposed methodology.


wireless and optical communications networks | 2012

Automated patch system to interface between HF and VHF radios with De-noising using wavelet transform

Rajorshee Raha; Arnab Pramanik

High frequency (HF),(3-30)MHz, and Very high frequency (VHF),(30-300)MHz, radio are the backbones of communication systems from many years. They are playing a major role in country wide communication system. Unfortunately there is no direct interface between these two radio frequencies. A lot of research work had been done to create a patch between HF radio and VHF radio. The main idea in this paper is to design an automated patch system to interface between HF and VHF radios. De-noising mechanism is used for noise reduction and a noise check mechanism is also used to ensure reliable communication. The patch system would be a bidirectional communication system to provide an interface between HF and VHF frequency ranges, and will not depend on any external signal rather will take the help of an internal signal to provide the interfacing.


arXiv: Systems and Control | 2015

Multi-mode Sampling Period Selection for Embedded Real Time Control

Rajorshee Raha; Soumyajit Dey; P. P. Chakrabarti; Pallab Dasgupta


Archive | 2013

HIGH SPEED INTEGRATED SIGNALING SYSTEM FOR UNDERGROUND MINES

Prabir Banerjee; Arnab Pramanik; Rajorshee Raha

Collaboration


Dive into the Rajorshee Raha's collaboration.

Top Co-Authors

Avatar

Pallab Dasgupta

Indian Institute of Technology Kharagpur

View shared research outputs
Top Co-Authors

Avatar

Soumyajit Dey

Indian Institute of Technology Kharagpur

View shared research outputs
Top Co-Authors

Avatar

Arnab Pramanik

Indian Institute of Technology Kharagpur

View shared research outputs
Top Co-Authors

Avatar

P. P. Chakrabarti

Indian Institute of Technology Kharagpur

View shared research outputs
Top Co-Authors

Avatar

Prabir Banerjee

Heritage Institute of Technology

View shared research outputs
Top Co-Authors

Avatar

Akash Mondal

Indian Institute of Technology Kharagpur

View shared research outputs
Top Co-Authors

Avatar

Aritra Hazra

Indian Institute of Technology Kharagpur

View shared research outputs
Top Co-Authors

Avatar

Souradeep Dutta

Indian Institute of Technology Kharagpur

View shared research outputs
Researchain Logo
Decentralizing Knowledge