A Novel Adaptive Optimized Fast Blind Channel Estimation for Cyclic Prefix Assisted Space–Time Block Coded MIMO-OFDM Systems

In this paper an adaptive optimized fast blind channel estimation using cyclic prefix supported with Space Time Block Coded Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing (STBC-MIMO-OFDM) system is presented. The main aspire of our technique is to support multiple users at the same time over same frequency band based on the Multi-Carrier Code-Division Multiple Access (MC-CDMA) approach. High complexity and low convergence is the main obstacle in earlier blind channel estimation techniques. Modified flower pollination algorithm is implemented to overcome this problem. The MC-CDMA approach is utilized to implement the blind channel estimation. The proposed MC-CDMA is used to reduce the error rate included in the Blind Channel Estimation. As a part of wireless communications, time block coding technique is utilized to transmit several copies of information across the number of antennas. To develop the consistency of data transfer different received data is used and then MFPA results in lower fuel cost compared to FPA. MFPA produces better results compared with previous methods.

     

Comparative study of FFA architectures using different multiplier and adder topologies

Parallel FIR filter is the prime block of many modern communication application such as MIMO, multi-point transceivers etc. But hardware replication problem of parallel techniques make the system more bulky and costly. Fast FIR algorithm (FFA) gives the best alternative to traditional parallel techniques. In this paper, FFA based FIR structures with different topologies of multiplier and adder are implemented. To optimize design different multiplication technique like add and shift method, Vedic multiplier and booth multiplier are used for computation. Various adders such as carry select adder, carry save adder and Han-Carlson adder are analyzed for improved performance of the FFA structure. The basic objective is to investigate the performance of these designs for the tradeoffs between area, delay and power dissipation. Comparative study is carried out among conventional and different proposed designs. The advantage of presented work is that; based on the constraints, one can select the suitable design for specific application. It also fulfils the literature gap of critical analysis of FPGA implementation of FFA architecture using different multiplier and adder topologies. Xilinx Vivado HLS tool is used to implement the proposed designs in VHDL.

     

Design and analysis of high-speed 8-bit ALU using 18 nm FinFET technology

All modern computational devices consist of ALU. With increase in complexity of software and the consistent shift of software towards parallelism, high speed processors with hardware support for time consuming operations such as multiplication would benefit. Smaller, compact devices such as IoT devices need to run software such as security software and be able to offload computation cost from the cloud. In this paper, a high speed 8-bit ALU using 18 nm FinFET technology is proposed. The arithmetic and logical unit consists of fast compute units such as Kogge Stone fast adder and Dadda multiplier along with basic logic gates. In this paper, an ALU with each compute unit optimized for speed is proposed, while responsibly consuming area. Dadda multiplier is of 8 × 8 architecture as opposed to conventional approach of 4 × 4 making it a true 8-bit ALU. Simulation and analysis is done using Cadence Virtuoso in Analog Design Environment. The transistor count of proposed design is 5298, the power consumption is 219 µW and maximum delay is 166.8 ps. The design is also expected to consume a maximum of one clock cycle for any computation.

     

A 0.6 V 117 nW high performance energy efficient system-on-chip (SoC) CMOS temperature sensor in 0.18 µm CMOS for aerospace applications

This research article presents and describes a novel design with improved performance low power consumption threshold voltage based CMOS thermal sensor for aerospace applications. The proposed temperature sensor utilizes the change in behavior of threshold voltage of MOSFET with variation in temperature. The challenge while designing the temperature sensor was to achieve the linearize output voltage with respect to change in temperature. Process corner analysis has been done to check the robustness of the circuit while performance analysis and sensitivity of the temperature sensor have been verified in the occurrence of parasitic. The proposed temperature sensor is featured with low power consumption, less power supply voltage utilization, high performance and sensitivity with inaccuracy as low as possible. The presented temperature sensor utilizes an active area of 18 µm × 9.85 µm with 117 nW power consumption. An improved linear performance with an inaccuracy of merely − 0.01 to + 0.47 °C over a wide temperature range of − 20 to + 120 °C is presented here. The sensitivity of proposed temperature sensor is found to be as high as 0.77 mV/°C. The proposed temperature sensor is realized and tested in Cadence virtuoso mixed signal design atmosphere using 0.18 µm CMOS technology and further investigated with support of tool from Mentor graphics. The engaged area of pad-limited chip is measured to be 0.96 mm².

     

Origin of Current‐Controlled Negative Differential Resistance Modes and the Emergence of Composite Characteristics with High Complexity

Current‐controlled negative differential resistance has significant potential as a fundamental building block in brain‐inspired neuromorphic computing. However, achieving the desired negative differential resistance characteristics, which is crucial for practical implementation, remains challenging due to a lack of consensus on the underlying mechanism and design criteria. Here, a material‐independent model of current‐controlled negative differential resistance is reported to explain a broad range of characteristics, including the origin of the discontinuous snap‐back response observed in many transition metal oxides. This is achieved by explicitly accounting for a non‐uniform current distribution in the oxide film and its impact on the effective circuit of the device rather than a material‐specific phase transition. The predictions of the model are then compared with experimental observations to show that the continuous S‐type and discontinuous snap‐back characteristics serve as fundamental building blocks for composite behavior with higher complexity. Finally, the potential of our approach is demonstrated for predicting and engineering unconventional compound behavior with novel functionality for emerging electronic and neuromorphic computing applications.     

Conductivity studies of poly (vinyl alcohol)-iodine complex membrane

Summary The conductivities of polymers like poly (vinyl alcohol) (PVA) and its iodine complex membranes are reported here. PVA-iodine complex membrane was prepared by dipping PVA film into an I₂–KI solution. The formation of the complex membrane was confirmed by IR spectra. Conductivities were determined from 30 to 300 °C with a frequency ranges from 42 Hz to 500 KHz in solid state. It was observed that iodine is known to act as a catalyst for dehydration of PVA. A possible mechanism for the dehydration of PVA catalyzed by iodine is also explained.     

Rheological studies on cordierite honeycomb extrusion

The rheological parameters for a cordierite honeycomb extrusion were investigated using the Benbow–Bridgwater model. The extrusion pastes were formulated using typical binders, plasticizers, lubricants and pore-forming agents normally used for such extrusions. Pastes were found to have good pseudo-plasticity, low bulk yield and very low die-land shear stress, compared with the velocity dependent components of the respective pressure drops. In some formulation, reduced velocity contribution to the extrusion pressure with increased binder content found useful for better honeycomb extrusion. These characteristics of the honeycomb extrusion batches were analyzed by using dynamic bulk and shear stress components derived from the Benbow–Bridgwater six-parameter model and compared with the results of honeycomb extrusion trials. Plasticizing agents like polyethylenglycol (PEG) and glycerin were found to decrease the die entry pressure but showed no external lubricating effect leading to higher die-land pressure. Pore-forming agent, graphite was found to reduce both die entry and die land pressures, whereas, carbon increases the die entry pressure.     

Microstructural characterization of TRIP-aided steels

Cold rolled steel sheets containing 0.4C, 0.5Si, 1.5Mn, 1.0Al, 0.02Nb and 0.1Mo (mass%) were subjected to three heat treatment schedules to produce TRIP-aided steels with annealed martensite (AM), bainitic ferrite (BF) and polygonal ferrite (PF) matrix microstructures. The distribution of different phases in these three varieties of steels was estimated using some existing quantitative relationships. In most of the cases, distribution of different constituents of the microstructure and the partitioning of carbon among the different phases could be estimated.     

Machine intelligence (MI), competence and creativity

In mid-twentieth century, the hypothesis, ‘a machine can think’ became very popular after, Alan Turing’s article on ‘Computing Machinery and Intelligence’. This hypothesis, ‘a machine can think’ established the foundations of machine intelligence (MI), and claimed that machines have consciousness and creativity, with the power to compete with human beings. In the first section, I shall show how consciousness and creativity is conceptualized in the domain of MI. The main aim of MI is not only to construct difficult programs to solve our day-to-day problems, but also to reproduce mentality in machines. It was claimed that all the mental qualities are ascribable to machines. My intention in this paper is to clarify consciousness and creativity from a subjective point of view. My claim is that consciousness and creativity cannot be fully represented in a mechanistic domain. There are subjective mental or conscious states, which can be seen in a first-person perspective of their proper understanding.