shanmukha swamy - Academia.edu (original) (raw)

Papers by shanmukha swamy

Research paper thumbnail of Performance Analysis of MIMO-OFDM Wireless Communication System through Channel Estimation

Future wireless communication system have to be designed to integrate features such as high data ... more Future wireless communication system have to be designed to integrate features such as high data rates, high quality of service and multimedia in the existing communication frame work. Increased demand in wireless communication system has led to demand for higher network capacity and performance. Higher bandwidth, optimized modulation offer practically limited potential to increase the spectral efficiency. Hence MIMO systems utilizes space multiplex by using array of antenna’s for enhancing the efficiency at particular utilized bandwidth.OFDM-based air interface, spatial channel modelling, transceiver design, channel estimation and minimizing the BER ratio by modifying the Maximum Likelihood function through channel estimation.

Research paper thumbnail of Microcontroller Based Real Time Weather Monitoring Device with GSM

The measurements of temperature, atmospheric pressure, relative humidity and dew point temperatur... more The measurements of temperature, atmospheric pressure, relative humidity and dew point temperature remotely by using the sensors is not only important in weather monitoring but also crucial for many other applications like agricultural and industrial processes. A device for real time weather monitoring is presented in this paper to monitor the real time temperature, atmospheric pressure, relative humidity and dew point temperature of the atmosphere via GSM network, using analogue and digital components. The analogue outputs of the sensors are connected to a microcontroller through an ADC for digital signal conversion. An LCD display is also connected to the microcontroller to display the measurements. For analysis and archiving purposes, the data can be transferred over GSM and receiver section is connected to PC. Received data is further processed to generate graphical display using weather modeling algorithms. The device has many advantages compared to other weather monitoring systems in terms of its smaller size, on-device display, low cost, portable and robust.

Research paper thumbnail of Design & Implementation of Optimized DMWT Architecture for OFDM on FPGA

To cater the growing wireless broad band aspirations in the market, new technologies are emerging... more To cater the growing wireless broad band aspirations in the market, new technologies are emerging to take up the challenges. Accordingly requirements for the next generation technologies have started building up and have led to unprecedented demand for high speed architectures for complex signal processing applications. In this work a GHM (Geronimo, Hardian, and Massopust) filter based DMWT and IDMWT is implemented on FPGA optimizing area, power and speed performances. The model is simulated using simulink and tested for its functionality using HDL code and is synthesized using Xilinx ISE targeting Virtex-5 FPGA. The performances of DMWT-OFDM in terms of BER show that DMWT-OFDM achieves higher BER performances compared with DWT-OFDM and FFT-OFDM.The proposed DMWT architecture operates at a maximum frequency of 340MHz and consumes power of 24mW.

Research paper thumbnail of Future Generation Ultra Supercomputing 256 × 256 Bits Multiplier for Signed-Unsigned Number

With the future 1 nm Hybrid CMOS technology, we proposed the Future Generation Ultra Supercomputi... more With the future 1 nm Hybrid CMOS technology, we proposed the Future Generation Ultra Supercomputing 256 × 256 Bits Multiplier for Signed-Unsigned Number. The Hybrid CMOS consists of the CMOS and Complimentary Pass Transistor Logic (CPTL). With the 1 nm future technology the various parameters predicted are the critical path delay of 0.1 ns (10 GHz), chip area of 136.23 μm and the power dissipation of 1171.4 μW.

Research paper thumbnail of Survey on Different Types of Channel Estimation Techniques in MIMO-OFDM Communication Systems

A Modern wireless broadband system of MIMO-OFDM (multiple input multiple outputorthogonal frequen... more A Modern wireless broadband system of MIMO-OFDM (multiple input multiple outputorthogonal frequency division multiplexing) is more popular because of good data transmission rate and its robustness against multipath fading & good spectral efficiency. This system provides reliable communication & wide coverage. A main challenge to MIMO-OFDM system is retrieval of the channel state information (CSI)accurately and synchronization between the transmitter & receiver. The channel state information is retrieved with the help of various estimation algorithms such as training based, blind and semi blind channel Estimation. This paper describes the basic introduction of OFDM, MIMO-OFDM system and explains the different channel estimation algorithms, optimization techniques and their utilization in MIMO system for 4G wireless mobile communication systems. Key Words— Channel Estimation, LS Estimation, MMSE Estimation, CSI, Mean Square Error.

Research paper thumbnail of BIST-Based Low Power Test Vector Generator and Minimizing Bulkiness of VLSI Architecture

Journal of Circuits, Systems and Computers

In several pseudorandom built-in self-test (BIST) circuits, the applied test vectors will be gene... more In several pseudorandom built-in self-test (BIST) circuits, the applied test vectors will be generated by a linear feedback shift register (LFSR). This type of test pattern generator (TPG) may generate some repeated test patterns, which unnecessarily increases the test power without contributing much to the fault coverage. Based on the vast designs of TPG engine, the chip area also increases by contributing for the overall power consumption of the IC. This paper presents an approach called low power — bit complements test vector generation (LP-BCTVG) technique with bipartite (half fixed) and bit insertion (either 0 or 1) techniques. In order to reduce the test power, the LP-BCTVG inserts appropriate intermediate vectors in between consecutive test vectors generated by LFSR circuit. Hence, the application of final output vectors of LP-BCTVG circuit over circuit under test decreases the test power compared with LFSR-based BIST. By complementing the output bits of LP-BCTVG, we can redu...

Research paper thumbnail of Designing an Efficient Multimodal Biometric System using Palmprint and Speech Signal

This paper proposes a multimodal biometric system using palmprint and speech signal. In this pape... more This paper proposes a multimodal biometric system using palmprint and speech signal. In this paper, we propose a novel approaches for both the modalities. We extract the features using Subband Cepstral Coefficients for speech signal and Modified Canonical method for palmprint. The individual feature score are passed to the fusion level. Also we have proposed a new fusion method called weighted score. This system is tested on clean and degraded database collected by the authors for more than 300 subjects. The results show significant improvement in the recognition rate.

Research paper thumbnail of Power Reduction Technique in LFSR Using Modified Control Logic for VLSI Circuit

International Journal of Computer Applications

ABSTRACT

Research paper thumbnail of Minimizing Test Power in Vlsi Architecture Using Bist Based Low-Transition Test Pattern Generation Technique

The Integrated circuit (IC) contains Built-In Self-Test (BIST) and circuit under test (CUT), to t... more The Integrated circuit (IC) contains Built-In Self-Test (BIST) and circuit under test (CUT), to test the correct functionality of any integrated circuit, test patterns are generated from Built In Self Test and then same generated test patterns are applied to the Circuit-under-Test (CUT), minimizing hardware overhead is a major concern of BIST implementation. In pseudo-random BIST design, the test vectors are generated with the help of Linear Feedback Shift Registers (LFSR) and which is called as conventional LFSR. The main drawback of these conventional LFSRs is, it generates normally more number of random natured test vectors for testing the CUT in which many are repeated patterns and application of which unnecessarily increase the test power without contributing much to the fault coverage. Apart from this, as the bulkiness of the CUT increases, the test vector generating engine is even becomes large in terms of number of sequential or test vector generating element. So that it could generate as many numbers of vectors which can fits the number of I/O pins of CUT logic or part of CUT logic. Thus, the increase in size of test circuit also requires the considerable die size on IC. This paper presents a new approach, called Linear feedback shift register-Bit complement test pattern generation technique (LFSR-BCTPG). In LFSR-BCTPG technique, the output bits are complemented due to which unrepeated test vectors are increased also by which better fault coverage with reduction in the bulkiness of the test circuit can be achieved. Hence, in this approach, the proposed test circuit can be half in size, compared to other conventional test circuits to test a particular CUT. The final results of proposed approach have been compared with other methods and found that, this method is better in terms of dynamic power dissipation when applying the test vectors generated by the proposed method to four different ISCAS'89 benchmark circuits.

Research paper thumbnail of Implementation of Channel Estimation and Modulation Technique for MIMO System

International Journal of Wireless & Mobile Networks, 2011

Future wireless communication system have to be designed to integrate features such as high data ... more Future wireless communication system have to be designed to integrate features such as high data rates, high quality of service and multimedia in the existing communication framework. Increased demand in wireless communication system has led to demand for higher network capacity and performance. Higher bandwidth, optimized modulation offer practically limited potential to increase the spectral efficiency. Hence MIMO systems utilizes space multiplex by using array of antenna's for enhancing the efficiency at particular utilized bandwidth. MIMO use multiple inputs multiple outputs from single channel. These systems defined by spectral diversity and spatial multiplexing. The aim of this paper is to design and implement of channel estimation method and modulation technique for MIMO system. The design specifications are obtained using MATLAB. The RTL coding is carried for the design to be implemented on Xilinx FPGA.

Research paper thumbnail of Performance analysis of DWT based OFDM over FFT based OFDM and implementing on FPGA

International Journal of VLSI Design & Communication Systems, 2011

Growth in technology has led to unprecedented demand for high speed architectures for complex sig... more Growth in technology has led to unprecedented demand for high speed architectures for complex signal processing applications. In 4G wireless communication systems, bandwidth is a precious commodity, and service providers are continuously met with the challenge of accommodating more users with in a limited allocated bandwidth. To increase data rate of wireless medium with higher performance, OFDM (orthogonal frequency division multiplexing) is used. Recently DWT (Discrete wavelet transforms) is adopted in place of FFT (Fast Fourier transform) for frequency translation. Modulation schemes such as 16-QAM, 32-QAM, 64-QAM and 128-QAM (Quadrature amplitude modulation) have been used in the developed OFDM system for both DWT and FFT based model. In this paper we propose a DWT-IDWT based OFDM transmitter and receiver that achieve better performance in terms SNR and BER for AWGN channel. It proves all the wavelet families better over the IFFT-FFT implementation. The OFDM model is developed using Simulink, various test cases have been considered to verify its performance. The DWT-OFDM using Lifting Scheme architecture is implemented on FPGA optimizing hardware, speed & cost. The wavelet filter used for this is Daubechies (9, 7) with N=2. The RTL code is written in Verilog-HDL and simulated in Modelsim. The design is then synthesized in Xilinx and implemented on Virtex5 FPGA board and the results were validated using ChipScope.

Research paper thumbnail of Low Power Pipelined Dwt-Idwt Architecture for Ofdm System on Fpga

Procedia Engineering, 2012

Abstract OFDM systems are widely used in most of the wireless communication systems. OFDM achieve... more Abstract OFDM systems are widely used in most of the wireless communication systems. OFDM achieves better bandwidth efficiency and data rate. FFT module in OFDM system is being replaced with DWT to reduce complexities in hardware implementation. In this paper, we propose a modified Distributive Arithmetic (DA) based DWT architecture for OFDM system. The proposed module is implemented on FPGA and its performances are compared with parallel and pipelined DA DWT architecture. The proposed DWT logic operates at a maximum frequency of 378MHz and consumes power less than 26 mW. The memory size is reduced from 256 bytes to 16 bytes thus saving large storage space on FPGA. Functional verification of the developed system is carried out using modelsim. Simulink models for the OFDM unit are developed and performances are estimated.

Research paper thumbnail of A biometric identification system based on the fusion of palmprint and speech signal

2010 International Conference on Signal and Image Processing, 2010

Abstract Biometric systems allow automatic person recognition based on physical or behavioral fea... more Abstract Biometric systems allow automatic person recognition based on physical or behavioral features which belong to a certain person. Each biometric feature has its limits and no biometric system is perfect so unimodal biometric systems raise a variety of ...

Research paper thumbnail of An efficient multimodal biometric face recognition using speech signal

2010 International Conference on Signal and Image Processing, 2010

Multimodal biometric face recognition using speech signal has engrossed much attention and has be... more Multimodal biometric face recognition using speech signal has engrossed much attention and has been applied in various domains primarily for surveillance, security & access control and law enforcement. In recent years much advancement have been made in face recognition techniques to cater to the challenges such as pose, expression, illumination, aging and disguise. However, due to advances in technology, there are new emerging challenges for which the performance of face recognition systems degrades and plastic/cosmetic surgery is one of them. In this paper we comment on the effect of plastic surgery face image in multimodal biometric face recognition using speech signal. Speaker identity is correlated with the physiological and behavioral characteristics of the speaker. These characteristics exist both in the spectral envelope (vocal tract characteristics) and in the suprasegmental features (voice source characteristics and dynamic features spanning several segments). Selecting the most effective fusion techniques depends on operational issues such as accuracy requirements, availability of training data, and the validity of simplifying assumptions.

Research paper thumbnail of High Speed Modified Booth Encoder Multiplier for Signed and Unsigned Numbers

2012 UKSim 14th International Conference on Computer Modelling and Simulation, 2012

This paper presents the design and implementation of signed-unsigned Modified Booth Encoding (SUM... more This paper presents the design and implementation of signed-unsigned Modified Booth Encoding (SUMBE) multiplier. The present Modified Booth Encoding (MBE) multiplier and the Baugh-Wooley multiplier perform multiplication operation on signed numbers only. The array multiplier and Braun array multipliers perform multiplication operation on unsigned numbers only. Thus, the requirement of the modern computer system is a dedicated and very high speed unique multiplier unit for signed and unsigned numbers. Therefore, this paper presents the design and implementation of SUMBE multiplier. The modified Booth Encoder circuit generates half the partial products in parallel. By extending sign bit of the operands and generating an additional partial product the SUMBE multiplier is obtained. The Carry Save Adderr (CSA) tree and the final Carry Look ahead (CLA) adder used to speed up the multiplier operation. Since signed and unsigned multiplication operation is performed by the same multiplier unit the required hardware and the chip area reduces and this in turn reduces power dissipation and cost of a system.

Research paper thumbnail of An efficient multimodal biometric face recognition using speech signal

Multimodal biometric face recognition using speech signal has engrossed much attention and has be... more Multimodal biometric face recognition using speech signal has engrossed much attention and has been applied in various domains primarily for surveillance, security & access control and law enforcement. In recent years much advancement have been made in face recognition techniques to cater to the challenges such as pose, expression, illumination, aging and disguise. However, due to advances in technology, there are new emerging challenges for which the performance of face recognition systems degrades and plastic/cosmetic surgery is one of them. In this paper we comment on the effect of plastic surgery face image in multimodal biometric face recognition using speech signal. Speaker identity is correlated with the physiological and behavioral characteristics of the speaker. These characteristics exist both in the spectral envelope (vocal tract characteristics) and in the suprasegmental features (voice source characteristics and dynamic features spanning several segments). Selecting the...

Research paper thumbnail of High Speed Modified Booth Encoder Multiplier for Signed and Unsigned Numbers

This paper presents the design and implementation of signed-unsigned Modified Booth Encoding (SUM... more This paper presents the design and implementation of signed-unsigned Modified Booth Encoding (SUMBE) multiplier. The present Modified Booth Encoding (MBE) multiplier and the Baugh-Wooley multiplier perform multiplication operation on signed numbers only. The array multiplier and Braun array multipliers perform multiplication operation on unsigned numbers only. Thus, the requirement of the modern computer system is a dedicated and very high speed unique multiplier unit for signed and unsigned numbers. Therefore, this paper presents the design and implementation of SUMBE multiplier. The modified Booth Encoder circuit generates half the partial products in parallel. By extending sign bit of the operands and generating an additional partial product the SUMBE multiplier is obtained. The Carry Save Adderr (CSA) tree and the final Carry Look ahead (CLA) adder used to speed up the multiplier operation. Since signed and unsigned multiplication operation is performed by the same multiplier un...

Research paper thumbnail of Design and Analysis of NCO based OFDM model

International Journal of Intelligent Engineering Informatics, 2011

Today|s communication standards, such as Hiperlan/2, IEEE 802.11a/g, IEEE 802.16 and DVB, already... more Today|s communication standards, such as Hiperlan/2, IEEE 802.11a/g, IEEE 802.16 and DVB, already use OFDM for digital modulation. In this work, OFDM modulator and demodulator is designed using NCO-based logic. NCO designed can generate several frequencies that are required as per OFDM standards and supports 64, 32 and 16 subcarrier applications. The OFDM modulator and demodulator designed is modelled and validated against OFDM modulator with FFT logic. The NCO-based OFDM model reduces the computation time, thus improving latency and throughput. The NCO-based OFDM model is designed to operate with a sample time of 33 ?sec, and spurious free dynamic range of 48 dBc, frequency resolution of 30.5176 MHz. A channel with SNR of 60 dB is used for verification of developed OFDM model.

Research paper thumbnail of A biometric identification system based on the fusion of palmprint and speech signal

… and Image Processing (ICSIP), …, 2010

Biometric systems allow automatic person recognition based on physical or behavioral features whi... more Biometric systems allow automatic person recognition based on physical or behavioral features which belong to a certain person. Each biometric feature has its limits and no biometric system is perfect so unimodal biometric systems raise a variety of ...

Research paper thumbnail of Improved radix-4 and radix-8 FFT algorithms

Circuits and Systems, …, 2004

Page 1. IMPROVED RADIX-4 AND RADIX-8 FFT ALGORITHMS Saad Bouguezel, M. OmairAhmad, Fellow, IEEE, ... more Page 1. IMPROVED RADIX-4 AND RADIX-8 FFT ALGORITHMS Saad Bouguezel, M. OmairAhmad, Fellow, IEEE, and MNS Swamy, Fellow, IEEE ... [6] M. Hasan and T. Arslan, “ A coefficient memory ad-dressing scheme for VLSI implementation of FFT pro-cessors,” in Proc. ...

Research paper thumbnail of Performance Analysis of MIMO-OFDM Wireless Communication System through Channel Estimation

Future wireless communication system have to be designed to integrate features such as high data ... more Future wireless communication system have to be designed to integrate features such as high data rates, high quality of service and multimedia in the existing communication frame work. Increased demand in wireless communication system has led to demand for higher network capacity and performance. Higher bandwidth, optimized modulation offer practically limited potential to increase the spectral efficiency. Hence MIMO systems utilizes space multiplex by using array of antenna’s for enhancing the efficiency at particular utilized bandwidth.OFDM-based air interface, spatial channel modelling, transceiver design, channel estimation and minimizing the BER ratio by modifying the Maximum Likelihood function through channel estimation.

Research paper thumbnail of Microcontroller Based Real Time Weather Monitoring Device with GSM

The measurements of temperature, atmospheric pressure, relative humidity and dew point temperatur... more The measurements of temperature, atmospheric pressure, relative humidity and dew point temperature remotely by using the sensors is not only important in weather monitoring but also crucial for many other applications like agricultural and industrial processes. A device for real time weather monitoring is presented in this paper to monitor the real time temperature, atmospheric pressure, relative humidity and dew point temperature of the atmosphere via GSM network, using analogue and digital components. The analogue outputs of the sensors are connected to a microcontroller through an ADC for digital signal conversion. An LCD display is also connected to the microcontroller to display the measurements. For analysis and archiving purposes, the data can be transferred over GSM and receiver section is connected to PC. Received data is further processed to generate graphical display using weather modeling algorithms. The device has many advantages compared to other weather monitoring systems in terms of its smaller size, on-device display, low cost, portable and robust.

Research paper thumbnail of Design & Implementation of Optimized DMWT Architecture for OFDM on FPGA

To cater the growing wireless broad band aspirations in the market, new technologies are emerging... more To cater the growing wireless broad band aspirations in the market, new technologies are emerging to take up the challenges. Accordingly requirements for the next generation technologies have started building up and have led to unprecedented demand for high speed architectures for complex signal processing applications. In this work a GHM (Geronimo, Hardian, and Massopust) filter based DMWT and IDMWT is implemented on FPGA optimizing area, power and speed performances. The model is simulated using simulink and tested for its functionality using HDL code and is synthesized using Xilinx ISE targeting Virtex-5 FPGA. The performances of DMWT-OFDM in terms of BER show that DMWT-OFDM achieves higher BER performances compared with DWT-OFDM and FFT-OFDM.The proposed DMWT architecture operates at a maximum frequency of 340MHz and consumes power of 24mW.

Research paper thumbnail of Future Generation Ultra Supercomputing 256 × 256 Bits Multiplier for Signed-Unsigned Number

With the future 1 nm Hybrid CMOS technology, we proposed the Future Generation Ultra Supercomputi... more With the future 1 nm Hybrid CMOS technology, we proposed the Future Generation Ultra Supercomputing 256 × 256 Bits Multiplier for Signed-Unsigned Number. The Hybrid CMOS consists of the CMOS and Complimentary Pass Transistor Logic (CPTL). With the 1 nm future technology the various parameters predicted are the critical path delay of 0.1 ns (10 GHz), chip area of 136.23 μm and the power dissipation of 1171.4 μW.

Research paper thumbnail of Survey on Different Types of Channel Estimation Techniques in MIMO-OFDM Communication Systems

A Modern wireless broadband system of MIMO-OFDM (multiple input multiple outputorthogonal frequen... more A Modern wireless broadband system of MIMO-OFDM (multiple input multiple outputorthogonal frequency division multiplexing) is more popular because of good data transmission rate and its robustness against multipath fading & good spectral efficiency. This system provides reliable communication & wide coverage. A main challenge to MIMO-OFDM system is retrieval of the channel state information (CSI)accurately and synchronization between the transmitter & receiver. The channel state information is retrieved with the help of various estimation algorithms such as training based, blind and semi blind channel Estimation. This paper describes the basic introduction of OFDM, MIMO-OFDM system and explains the different channel estimation algorithms, optimization techniques and their utilization in MIMO system for 4G wireless mobile communication systems. Key Words— Channel Estimation, LS Estimation, MMSE Estimation, CSI, Mean Square Error.

Research paper thumbnail of BIST-Based Low Power Test Vector Generator and Minimizing Bulkiness of VLSI Architecture

Journal of Circuits, Systems and Computers

In several pseudorandom built-in self-test (BIST) circuits, the applied test vectors will be gene... more In several pseudorandom built-in self-test (BIST) circuits, the applied test vectors will be generated by a linear feedback shift register (LFSR). This type of test pattern generator (TPG) may generate some repeated test patterns, which unnecessarily increases the test power without contributing much to the fault coverage. Based on the vast designs of TPG engine, the chip area also increases by contributing for the overall power consumption of the IC. This paper presents an approach called low power — bit complements test vector generation (LP-BCTVG) technique with bipartite (half fixed) and bit insertion (either 0 or 1) techniques. In order to reduce the test power, the LP-BCTVG inserts appropriate intermediate vectors in between consecutive test vectors generated by LFSR circuit. Hence, the application of final output vectors of LP-BCTVG circuit over circuit under test decreases the test power compared with LFSR-based BIST. By complementing the output bits of LP-BCTVG, we can redu...

Research paper thumbnail of Designing an Efficient Multimodal Biometric System using Palmprint and Speech Signal

This paper proposes a multimodal biometric system using palmprint and speech signal. In this pape... more This paper proposes a multimodal biometric system using palmprint and speech signal. In this paper, we propose a novel approaches for both the modalities. We extract the features using Subband Cepstral Coefficients for speech signal and Modified Canonical method for palmprint. The individual feature score are passed to the fusion level. Also we have proposed a new fusion method called weighted score. This system is tested on clean and degraded database collected by the authors for more than 300 subjects. The results show significant improvement in the recognition rate.

Research paper thumbnail of Power Reduction Technique in LFSR Using Modified Control Logic for VLSI Circuit

International Journal of Computer Applications

ABSTRACT

Research paper thumbnail of Minimizing Test Power in Vlsi Architecture Using Bist Based Low-Transition Test Pattern Generation Technique

The Integrated circuit (IC) contains Built-In Self-Test (BIST) and circuit under test (CUT), to t... more The Integrated circuit (IC) contains Built-In Self-Test (BIST) and circuit under test (CUT), to test the correct functionality of any integrated circuit, test patterns are generated from Built In Self Test and then same generated test patterns are applied to the Circuit-under-Test (CUT), minimizing hardware overhead is a major concern of BIST implementation. In pseudo-random BIST design, the test vectors are generated with the help of Linear Feedback Shift Registers (LFSR) and which is called as conventional LFSR. The main drawback of these conventional LFSRs is, it generates normally more number of random natured test vectors for testing the CUT in which many are repeated patterns and application of which unnecessarily increase the test power without contributing much to the fault coverage. Apart from this, as the bulkiness of the CUT increases, the test vector generating engine is even becomes large in terms of number of sequential or test vector generating element. So that it could generate as many numbers of vectors which can fits the number of I/O pins of CUT logic or part of CUT logic. Thus, the increase in size of test circuit also requires the considerable die size on IC. This paper presents a new approach, called Linear feedback shift register-Bit complement test pattern generation technique (LFSR-BCTPG). In LFSR-BCTPG technique, the output bits are complemented due to which unrepeated test vectors are increased also by which better fault coverage with reduction in the bulkiness of the test circuit can be achieved. Hence, in this approach, the proposed test circuit can be half in size, compared to other conventional test circuits to test a particular CUT. The final results of proposed approach have been compared with other methods and found that, this method is better in terms of dynamic power dissipation when applying the test vectors generated by the proposed method to four different ISCAS'89 benchmark circuits.

Research paper thumbnail of Implementation of Channel Estimation and Modulation Technique for MIMO System

International Journal of Wireless & Mobile Networks, 2011

Future wireless communication system have to be designed to integrate features such as high data ... more Future wireless communication system have to be designed to integrate features such as high data rates, high quality of service and multimedia in the existing communication framework. Increased demand in wireless communication system has led to demand for higher network capacity and performance. Higher bandwidth, optimized modulation offer practically limited potential to increase the spectral efficiency. Hence MIMO systems utilizes space multiplex by using array of antenna's for enhancing the efficiency at particular utilized bandwidth. MIMO use multiple inputs multiple outputs from single channel. These systems defined by spectral diversity and spatial multiplexing. The aim of this paper is to design and implement of channel estimation method and modulation technique for MIMO system. The design specifications are obtained using MATLAB. The RTL coding is carried for the design to be implemented on Xilinx FPGA.

Research paper thumbnail of Performance analysis of DWT based OFDM over FFT based OFDM and implementing on FPGA

International Journal of VLSI Design & Communication Systems, 2011

Growth in technology has led to unprecedented demand for high speed architectures for complex sig... more Growth in technology has led to unprecedented demand for high speed architectures for complex signal processing applications. In 4G wireless communication systems, bandwidth is a precious commodity, and service providers are continuously met with the challenge of accommodating more users with in a limited allocated bandwidth. To increase data rate of wireless medium with higher performance, OFDM (orthogonal frequency division multiplexing) is used. Recently DWT (Discrete wavelet transforms) is adopted in place of FFT (Fast Fourier transform) for frequency translation. Modulation schemes such as 16-QAM, 32-QAM, 64-QAM and 128-QAM (Quadrature amplitude modulation) have been used in the developed OFDM system for both DWT and FFT based model. In this paper we propose a DWT-IDWT based OFDM transmitter and receiver that achieve better performance in terms SNR and BER for AWGN channel. It proves all the wavelet families better over the IFFT-FFT implementation. The OFDM model is developed using Simulink, various test cases have been considered to verify its performance. The DWT-OFDM using Lifting Scheme architecture is implemented on FPGA optimizing hardware, speed & cost. The wavelet filter used for this is Daubechies (9, 7) with N=2. The RTL code is written in Verilog-HDL and simulated in Modelsim. The design is then synthesized in Xilinx and implemented on Virtex5 FPGA board and the results were validated using ChipScope.

Research paper thumbnail of Low Power Pipelined Dwt-Idwt Architecture for Ofdm System on Fpga

Procedia Engineering, 2012

Abstract OFDM systems are widely used in most of the wireless communication systems. OFDM achieve... more Abstract OFDM systems are widely used in most of the wireless communication systems. OFDM achieves better bandwidth efficiency and data rate. FFT module in OFDM system is being replaced with DWT to reduce complexities in hardware implementation. In this paper, we propose a modified Distributive Arithmetic (DA) based DWT architecture for OFDM system. The proposed module is implemented on FPGA and its performances are compared with parallel and pipelined DA DWT architecture. The proposed DWT logic operates at a maximum frequency of 378MHz and consumes power less than 26 mW. The memory size is reduced from 256 bytes to 16 bytes thus saving large storage space on FPGA. Functional verification of the developed system is carried out using modelsim. Simulink models for the OFDM unit are developed and performances are estimated.

Research paper thumbnail of A biometric identification system based on the fusion of palmprint and speech signal

2010 International Conference on Signal and Image Processing, 2010

Abstract Biometric systems allow automatic person recognition based on physical or behavioral fea... more Abstract Biometric systems allow automatic person recognition based on physical or behavioral features which belong to a certain person. Each biometric feature has its limits and no biometric system is perfect so unimodal biometric systems raise a variety of ...

Research paper thumbnail of An efficient multimodal biometric face recognition using speech signal

2010 International Conference on Signal and Image Processing, 2010

Multimodal biometric face recognition using speech signal has engrossed much attention and has be... more Multimodal biometric face recognition using speech signal has engrossed much attention and has been applied in various domains primarily for surveillance, security & access control and law enforcement. In recent years much advancement have been made in face recognition techniques to cater to the challenges such as pose, expression, illumination, aging and disguise. However, due to advances in technology, there are new emerging challenges for which the performance of face recognition systems degrades and plastic/cosmetic surgery is one of them. In this paper we comment on the effect of plastic surgery face image in multimodal biometric face recognition using speech signal. Speaker identity is correlated with the physiological and behavioral characteristics of the speaker. These characteristics exist both in the spectral envelope (vocal tract characteristics) and in the suprasegmental features (voice source characteristics and dynamic features spanning several segments). Selecting the most effective fusion techniques depends on operational issues such as accuracy requirements, availability of training data, and the validity of simplifying assumptions.

Research paper thumbnail of High Speed Modified Booth Encoder Multiplier for Signed and Unsigned Numbers

2012 UKSim 14th International Conference on Computer Modelling and Simulation, 2012

This paper presents the design and implementation of signed-unsigned Modified Booth Encoding (SUM... more This paper presents the design and implementation of signed-unsigned Modified Booth Encoding (SUMBE) multiplier. The present Modified Booth Encoding (MBE) multiplier and the Baugh-Wooley multiplier perform multiplication operation on signed numbers only. The array multiplier and Braun array multipliers perform multiplication operation on unsigned numbers only. Thus, the requirement of the modern computer system is a dedicated and very high speed unique multiplier unit for signed and unsigned numbers. Therefore, this paper presents the design and implementation of SUMBE multiplier. The modified Booth Encoder circuit generates half the partial products in parallel. By extending sign bit of the operands and generating an additional partial product the SUMBE multiplier is obtained. The Carry Save Adderr (CSA) tree and the final Carry Look ahead (CLA) adder used to speed up the multiplier operation. Since signed and unsigned multiplication operation is performed by the same multiplier unit the required hardware and the chip area reduces and this in turn reduces power dissipation and cost of a system.

Research paper thumbnail of An efficient multimodal biometric face recognition using speech signal

Multimodal biometric face recognition using speech signal has engrossed much attention and has be... more Multimodal biometric face recognition using speech signal has engrossed much attention and has been applied in various domains primarily for surveillance, security & access control and law enforcement. In recent years much advancement have been made in face recognition techniques to cater to the challenges such as pose, expression, illumination, aging and disguise. However, due to advances in technology, there are new emerging challenges for which the performance of face recognition systems degrades and plastic/cosmetic surgery is one of them. In this paper we comment on the effect of plastic surgery face image in multimodal biometric face recognition using speech signal. Speaker identity is correlated with the physiological and behavioral characteristics of the speaker. These characteristics exist both in the spectral envelope (vocal tract characteristics) and in the suprasegmental features (voice source characteristics and dynamic features spanning several segments). Selecting the...

Research paper thumbnail of High Speed Modified Booth Encoder Multiplier for Signed and Unsigned Numbers

This paper presents the design and implementation of signed-unsigned Modified Booth Encoding (SUM... more This paper presents the design and implementation of signed-unsigned Modified Booth Encoding (SUMBE) multiplier. The present Modified Booth Encoding (MBE) multiplier and the Baugh-Wooley multiplier perform multiplication operation on signed numbers only. The array multiplier and Braun array multipliers perform multiplication operation on unsigned numbers only. Thus, the requirement of the modern computer system is a dedicated and very high speed unique multiplier unit for signed and unsigned numbers. Therefore, this paper presents the design and implementation of SUMBE multiplier. The modified Booth Encoder circuit generates half the partial products in parallel. By extending sign bit of the operands and generating an additional partial product the SUMBE multiplier is obtained. The Carry Save Adderr (CSA) tree and the final Carry Look ahead (CLA) adder used to speed up the multiplier operation. Since signed and unsigned multiplication operation is performed by the same multiplier un...

Research paper thumbnail of Design and Analysis of NCO based OFDM model

International Journal of Intelligent Engineering Informatics, 2011

Today|s communication standards, such as Hiperlan/2, IEEE 802.11a/g, IEEE 802.16 and DVB, already... more Today|s communication standards, such as Hiperlan/2, IEEE 802.11a/g, IEEE 802.16 and DVB, already use OFDM for digital modulation. In this work, OFDM modulator and demodulator is designed using NCO-based logic. NCO designed can generate several frequencies that are required as per OFDM standards and supports 64, 32 and 16 subcarrier applications. The OFDM modulator and demodulator designed is modelled and validated against OFDM modulator with FFT logic. The NCO-based OFDM model reduces the computation time, thus improving latency and throughput. The NCO-based OFDM model is designed to operate with a sample time of 33 ?sec, and spurious free dynamic range of 48 dBc, frequency resolution of 30.5176 MHz. A channel with SNR of 60 dB is used for verification of developed OFDM model.

Research paper thumbnail of A biometric identification system based on the fusion of palmprint and speech signal

… and Image Processing (ICSIP), …, 2010

Biometric systems allow automatic person recognition based on physical or behavioral features whi... more Biometric systems allow automatic person recognition based on physical or behavioral features which belong to a certain person. Each biometric feature has its limits and no biometric system is perfect so unimodal biometric systems raise a variety of ...

Research paper thumbnail of Improved radix-4 and radix-8 FFT algorithms

Circuits and Systems, …, 2004

Page 1. IMPROVED RADIX-4 AND RADIX-8 FFT ALGORITHMS Saad Bouguezel, M. OmairAhmad, Fellow, IEEE, ... more Page 1. IMPROVED RADIX-4 AND RADIX-8 FFT ALGORITHMS Saad Bouguezel, M. OmairAhmad, Fellow, IEEE, and MNS Swamy, Fellow, IEEE ... [6] M. Hasan and T. Arslan, “ A coefficient memory ad-dressing scheme for VLSI implementation of FFT pro-cessors,” in Proc. ...