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Wireless transmitters employing switching power amplifiers are popular both in RF and mm-wave designs. The efficiency of switching power amplifiers is dictated mainly by the maximum achievable switch size which in turn is governed by the switch transition frequency (tradeoff between switch on-resistance and capacitance). This paper presents a new architecture, the distributed switching power amplifier (DSPA), that helps break this tradeoff by distributing the switch in the nonlinear amplifier design, especially at high frequencies. A comprehensive analytical framework has been developed and the theory has been compared with simulation results.

The paper presents cooperative communication based wireless sensor network for monitoring Green house related parameters such as Temperature, humidity and Carbon-di-oxide. The system is demonstrated by using network simulator NS2 with increased network capacity to suit large geo graphical areas. The comparison results show that cooperative transmission provides better performance than non-cooperative transmission in various aspects, such as packet loss, packet delivery ratio (PDR), network capacity and throughput. It is observed that the energy efficient and successful transmission occurred within transmission range and better link quality. Further, the results proved that the transmission range increases as when throughput and packet delivery ratio are decreasing.

Network coding technique based wireless sensor network for environmental monitoring is described here. The network coding is implemented in CC2530 microcontroller and the performance of wireless sensor network is evaluated by analyzing packet delivery ratio (PDR) and packet error rate (PER). It is observed that the resources can be shared among the nodes with minimum number of transmission and repetition of packets can be reduced by using Network Coding.

The paper presents an indoor air quality monitoring system which comprises of real-time sensing unit that enables remote monitoring of environmental carbon-di-oxide, temperature, and relative humidity. The simple mail transfer protocol (SMTP)-based remote monitoring system employs an Internet of Things (IoT) signal processor (CC3100) interfaced on top of a low-power microcontroller (MSP430F5529). The system is also packed with a short messaging service (SMS)-based emergency alerting mechanism on the mobile network through SIM900 GSM module. The whole system when integrated with pre-calibrated non-dispersive infrared (COZIR) sensing unit showed good response in communicating the alert messages and E-mail. The information from sensing unit can be analyzed and logged for any period of time.

A real-time cooperative communication based wireless network is presented for monitoring health and activity of an end-user in their environment. The cooperative communication offers better energy consumption and also an opportunity to aware the current location of a user non-intrusively. The link between mobile sensor node and relay node is dynamically established by using Received Signal Strength Indicator (RSSI) and Link Quality Indicator (LQI) based on adaptive relay selection scheme. The study proposes a Linear Acceleration based Transmission Power Decision Control (LA-TPDC) algorithm to further enhance the energy efficiency of cooperative communication. Further, the occurrences of false alarms are carefully prevented by introducing three stages of sequential warning system. The real-time experiments are carried-out by using the nodes, namely mobile sensor node, relay nodes and a destination node which are indigenously developed by using a CC430 microcontroller integrated with an in-built transceiver at 868 MHz. The wireless node performance characteristics, such as energy consumption, Signal-Noise ratio (SNR), Bit Error Rate (BER), Packet Delivery Ratio (PDR) and transmission offset are evaluated for all the participated nodes. The experimental results observed that the proposed linear acceleration based transmission power decision control algorithm almost doubles the battery life time than energy efficient conventional cooperative communication.

This paper describes a wireless sensor network-based indoor air quality monitoring system. The indoor air quality defines the quality of the environment where people live. Here wireless sensor network serves as the tool for estimating the indoor air quality. The WSN comprises sensor nodes and a coordinator node which communicates using the IEEE 802.15.4 wireless standard ZigBee wireless module. The indoor air quality estimation is done by interfacing CO2, temperature and RH (Relative humidity) sensors with the sensor node. The sensor node gathers the sensor data and reports it to the coordinator for real-time monitoring using a GUI (Graphical user interface) developed in Java NetBeans to run on windows PC. The collected data can be used to maintain the environment parameters by interfacing it to a HVAC (Heating, Ventilation and Air Conditioning) system.

The next generation of technology is connecting to internet from a standalone device. The background of Internet of Things (IoT), which covers various areas like ubiquitous positioning, biometrics, energy harvesting technologies, and machine vision, makes researches to make deep study in these individual technologies. The paper presents human vital sign monitoring system which includes measurement of pulse rate and body temperature of patients from remote locations. Standalone device connectivity with Simple Mail Transfer Protocol (SMTP) server can be achieved by implementing a TCP/IP stack and Ethernet interface in a MSP430 controller. An IoT enabled network processor CC3100 and Computational processor MSP430 is interfaced with sensory components and made to communicate emergency signals through Global System for Mobile (GSM) and SMTP server. The sensors are pre-calibrated and the wireless system showed good response in sending messages and email. The physiological signals can be analyzed and data logged to identify history of ailments of particular user/patient. The system possesses the characteristics, such as less intrusiveness to the users and helps the caretakers as well as physicians with comfort in taking care of patients.

This paper demonstrates a 240GHz wideband QPSK transmitter in 65nm bulk CMOS. The proposed transmitter employs an 80GHz local oscillator, a quadrature differential hybrid, and a QPSK modulator. Additionally, an 80GHz class-E switching power amplifier is used to efficiently boost the phase-modulated wideband signal. A frequency tripler then regenerates the modulated signal at 240GHz while preserving the QPSK constellation. By using on-chip slotted loop antennas, the transmitter achieves an EIRP of 1dBm. A maximum data rate of 16Gbps is achieved with a total power consumption of 220mW.

DC Motors have taken a great evolution from older brushed DC motors to today's BLDC motor. It has wide range of applications and hence it needs to have a better lifetime with higher efficiency. So for giving a higher efficiency, better lifetime and to get a better performance Brushless DC motors are developed. This brushless DC motor provides a greater efficiency with its complexity for controlling as a tradeoff, i.e. to get a better efficiency the complexity of the controlling systems increases. The BLDC motor needs the help of sensor to estimate its rotor position details to get controlled by the controlling circuit, which will directly affects the cost of the system. Now the sensorless controlling mechanisms have been developed which have made the cost lesser and provides better stability. Such an efficient sensorless controlling mechanism is proposed in this paper.

Wheel Loaders are heavy earth movers used for rugged real-time works like Construction, mining, Carrying, Demolition, Excavation and Hauling. Wheel Loaders have only conventional and analog control panels and indicators to monitor the vehicle's engine parameters. The earth mover operators face the problems of using these control panels. This project proposes a solution for the above problem by developing a sophisticated digital display in order to display both text and graphical symbols. The Digital displays are controlled by microcontrollers which analyze the transducer values and provide summarized and efficient parameters to the control panel with high resolution. This would enhance the operation of Wheel loaders in terms of ease-of-use, lane keeping, efficiency, safety and productivity.

A fully integrated 260GHz OOK transceiver is demonstrated in 65nm CMOS. Communication at 10Gb/s has been verified over a range of 40 mm. The Tx/Rx dual on-chip antenna array is implemented with half-width leaky wave antennas. Each Tx consists of a quadrupler driven by a class-D−1 PA with a distributed OOK modulator, and outputs +5 dBm of EIRP. The Rx uses a double balanced mixer to down-convert to a V-band IF signal that is amplified with a wideband IF driver and demoduated on-chip.

Background: Human identification has been studied since fourteenth century and it has gradually advanced for forensic purposes. Traditional methods such as dental, fingerprint, and DNA comparisons are probably the most common techniques used in this context, allowing fast and secure identification processes. But, in circumstances where identification of an individual by fingerprint or dental record comparison is difficult, palatal rugae may be considered as an alternative source of material. Aim: The present study was done to evaluate the individualistic nature and use of palatal rugae patterns for personal identification and also to test the efficiency of computerized software for forensic identification by photographic superimposition of palatal photographs obtained from casts. Materials and Methods: Two sets of Alginate impressions were made from the upper arches of 100 individuals (50 males and 50 females) with one month interval in between and the casts were poured. All the teeth except the incisors were removed to ensure that only the palate could be used in identification process. In one set of the casts, the palatal rugae were highlighted with a graphite pencil. All the 200 casts were randomly numbered, and then, they were photographed with a 10.1 Mega Pixel Kodak digital camera using standardized method. Using computerized software, the digital photographs of the models without highlighting the palatal rugae were overlapped over the images (transparent) of the palatal rugae with highlighted palatal rugae, in order to identify the pairs by superimposition technique. Incisors were remained and used as landmarks to determine the magnification required to bring the two set of photographs to the same size, in order to make perfect superimposition of images. Results: The result of the overlapping of the digital photographs of highlighted palatal rugae over normal set of models without highlighted palatal rugae resulted in 100% positive identification. Conclusion: This study showed that utilization of palatal photographs is highly viable. The photographic superimposition technique using Adobe Photoshop 8.0 software (used in this study for comparison of palatal rugae) was proved effective for human identification and can be used when ante-mortem data regarding palatal rugae is provided. This study also concluded that palatal rugae are highly individualistic and play an important role as a complementary method in personal identification.