Shukri Korakkottil Kunhi Mohd

Bio: Shukri Korakkottil Kunhi Mohd is an academic researcher from Universiti Sains Malaysia. The author has contributed to research in topics: CMOS & Amplifier. The author has an hindex of 4, co-authored 22 publications receiving 44 citations. Previous affiliations of Shukri Korakkottil Kunhi Mohd include Universiti Sains Malaysia Engineering Campus.

Implementation of IEEE 802.15.4-based OQPSK-pulse-shaping block on FPGA

Abstract: This paper describes implementation of an offset quadrature phase shift keying (OQPSK)-pulse-shaping block as a part of digital transmitter The implementation is based on 24 GHz-band IEEE 802154 standard In this paper, the implementation results are compared to the results of OQPSK modulator and pulse-shaping block in terms of simulation waveform, design size, and synthesis run time These blocks were designed using Verilog code through Xilinx ISE as a new design method and been implemented on Spartan3E XC3S500E field programmable gate array (FPGA) Current review shows that configurations for the implementation of OQPSK-pulse-shaping block, require 264% slices, 229% sliced flip-flops, and 155% look-up tables (LUTs), which is much better than the results of OQPSK modulator and pulse-shaping block At clock frequencies of 2 MHz and 25 MHz, the synthesis run time for OQPSK-pulse-shaping block shows substantial improvement with 48 ns faster than the two blocks

Development of the CRC block for Zigbee Standard on FPGA

Abstract: CRC (Cyclic Redundancy Check) block was developed on FPGA (Field Programmable Gate Array) in order to meet the needs for simple, low-power and low-cost wireless communication such as Zigbee Zigbee operates primarily in the 24 GHz band, which makes the technology easily applicable and worldwide available This paper gives a short overview of CRC block in the digital transmitter based on Zigbee Standard The purpose of the research is to diversify the design methods by using the Verilog code entry through Xilinx ISE 82i Here, the simulation and measurement results are also presented to verify the functionality of the CRC block The data rate of CRC block is 250 kbps

Effect of working fluid, acceleration and heater power on temperature profile inside a thermal convective accelerometer

Abstract: Convective accelerometer does not contain seismic mass and work based on free convection heat transfer of electrical heater inside a hermetic chamber. Its sensitivity is dependent to the temperature distribution of working fluid inside the hermetic chamber. In this paper, the effect of working fluid properties, acceleration and heater power on temperature profile inside the convective accelerometer hermetic chamber is presented. Convective accelerometers with various working fluids (air, carbon dioxide, water, nitrogen, argon, helium, and ethylene glycol), heater powers (0.1 to 1.0 watts), and accelerations (1 to 5 g) were simulated by using ConventorWare 2010 software. Result shows, without acceleration the temperature profile of working fluid is symmetry around the vertical axis in relation to the heat source while with acceleration, the temperature profile is slightly skewed towards the acceleration direction. Argon is the best candidate for working fluid because it produces the largest temperature difference between the left and the right sides of the heater which would result in high sensitivity accelerometer. Convective accelerometer sensitivity also can be enhanced by increasing heater power, using gas-phase working fluids and locating the temperature sensors in the range between 100 to 300 μm away from the heater.

Development of Bit-to-Chip Block for Zigbee Transmitter on FPGA

Abstract: Digital transmitter was developed on FPGA (Field Programmable Gate Array) in order to meet the needs for simple, low-power and low-cost wireless communication such as Zigbee. Zigbee operates primarily in the 2.4 GHz band, which makes the technology easily applicable and worldwide available. However, this paper only covers the bit-to-symbol block and the symbol-to-chip block of the digital transmitter for an acknowledgment frame. These two blocks are combined together as bit-to-chip block before implemented on Spartan3E XC3S500E FPGA. The purpose of the research is to diversify the design methods by using the Verilog code entry through Xilinx ISE 8.2i. Here, the simulation and measurement results are also presented to verify the functionality of the combined block. The frequency for input data and output data are 250 kHz and 2 MHz respectively.

Low velocity impact and compression after impact properties on gamma irradiated Kevlar/oil palm empty fruit bunch hybrid composites

Abstract: This work investigates the dynamic impact response of Kevlar/oil palm empty fruit bunch (EFB) hybrid composite structures with/without gamma radiation under low velocity impact (LVI) and compression after impact (CAI) test. The layering pattern Kevlar/oil palm EFB/Kevlar (K/OP/K) was applied in this work. Irradiation with gamma ray with various doses were applied from 25–150 kGy. LVI results shows that hybrid Kevlar/oil palm EFBs (Kevlar/OPEFB) that were not irradiated have greater impact resistance as compared to irradiated hybrid Kevlar/OPEFB. It was also observed that the hybridization of Kevlar/OPEFB with gamma irradiation helped to improve the compressive residual strength of the composites. It was found that Kevlar/OPEFB hybrid composites with the layering sequence K/OP/K can withstand up to 35 J of impact energy, with the optimum gamma radiation dose at 50 kGy.

The Design of CMOS Radio-Frequency Integrated Circuits: RF CIRCUITS THROUGH THE AGES

Abstract: This expanded and thoroughly revised edition of Thomas H. Lee's acclaimed guide to the design of gigahertz RF integrated circuits features a completely new chapter on the principles of wireless systems. The chapters on low-noise amplifiers, oscillators and phase noise have been significantly expanded as well. The chapter on architectures now contains several examples of complete chip designs that bring together all the various theoretical and practical elements involved in producing a prototype chip. First Edition Hb (1998): 0-521-63061-4 First Edition Pb (1998); 0-521-63922-0

Field Programmable Gate Array Applications—A Scientometric Review

Abstract: Field Programmable Gate Array (FPGA) is a general purpose programmable logic device that can be configured by a customer after manufacturing to perform from a simple logic gate operations to complex systems on chip or even artificial intelligence systems. Scientific publications related to FPGA started in 1992 and, up to now, we found more than 70,000 documents in the two leading scientific databases (Scopus and Clarivative Web of Science). These publications show the vast range of applications based on FPGAs, from the new mechanism that enables the magnetic suspension system for the kilogram redefinition, to the Mars rovers’ navigation systems. This paper reviews the top FPGAs’ applications by a scientometric analysis in ScientoPy, covering publications related to FPGAs from 1992 to 2018. Here we found the top 150 applications that we divided into the following categories: digital control, communication interfaces, networking, computer security, cryptography techniques, machine learning, digital signal processing, image and video processing, big data, computer algorithms and other applications. Also, we present an evolution and trend analysis of the related applications.

Critical Review of Natural Fiber Reinforced Hybrid Composites: Processing, Properties, Applications and Cost

Abstract: Increasing scientific interest has occurred concerning the utilization of natural fiber-enhanced hybrid composites that incorporate one or more types of natural enhancement. Annual natural fiber production is estimated to be 1,783,965 × 103 tons/year. Extensive studies have been conducted in the domains of natural/synthetic as well as natural/natural hybrid composites. As synthetic fibers have better rigidity and strength than natural fibers, natural/synthetic hybrid composites have superior qualities via hybridization compared to natural composites in fibers. In general, natural fiber compounds have lower characteristics, limiting the use of natural composites reinforced by fiber. Significant effort was spent in enhancing the mechanical characteristics of this group of materials to increase their strengths and applications, especially via the hybridization process, by manipulating the characteristics of fiber-reinforced composite materials. Current studies concentrate on enhancing the understanding of natural fiber-matrix adhesion, enhancing processing methods, and natural fiber compatibility. The optimal and resilient conceptions have also been addressed due to the inherently more significant variabilities. Moreover, much research has tackled natural fiber reinforced hybrid composite costs. In addition, this review article aims to offer a review of the variables that lead to the mechanical and structural failure of natural fiber reinforced polymer composites, as well as an overview of the details and costings of the composites.

A Review of Micromachined Thermal Accelerometers

Abstract: Thermal convection based micro-electromechanical accelerometer is a relatively new kind of acceleration sensor that does not require a solid proof mass, yielding unique benefits like high shock survival rating, low production cost, and integrability with CMOS integrated circuit technology. This article provides a comprehensive survey of the research, development, and current trends in the field of thermal acceleration sensors, with detailed enumeration on the theory, operation, modeling, and numerical simulation of such devices. Different reported varieties and structures of thermal accelerometers have been reviewed highlighting key design, implementation, and performance aspects. Materials and technologies used for fabrication of such sensors have also been discussed. Further, the advantages and challenges for thermal accelerometers vis-a-vis other prominent accelerometer types have been presented, followed by an overview of associated signal conditioning circuitry and potential applications.

A review of micromachined thermal accelerometers

Abstract: Thermal convection based micro-electromechanical accelerometer is a relatively new kind of acceleration sensor that does not require a solid proof mass, yielding unique benefits like high shock survival rating, low production cost, and integrability with CMOS integrated circuit technology. This article provides a comprehensive survey of the research, development, and current trends in the field of thermal acceleration sensors, with detailed enumeration on the theory, operation, modeling, and numerical simulation of such devices. Different reported varieties and structures of thermal accelerometers have been reviewed highlighting key design, implementation, and performance aspects. Materials and technologies used for fabrication of such sensors have also been discussed. Further, the advantages and challenges for thermal accelerometers vis-a-vis other prominent accelerometer types have been presented, followed by an overview of associated signal conditioning circuitry and potential applications.