Dwipjoy Sarkar

A Real Time Embedded System Application for Driver Drowsiness and Alcoholic Intoxication Detection

This paper outlines a novel approach for the real time detection of car driver drowsiness and alcoholic intoxication. There are large numbers of road accidents which takes place due to fatigue or alcohol drinking of driver. Computer vision and alcohol gas sensor application is combined to an embedded system to achieve this goal. The proposed system is realized with an open source 5 megapixel digital camera supported embedded system board Raspberry-pi loaded with Raspbian-OS, and Python-IDLE with Open-CV installed. The Raspberry-pi system board is serially interfaced with another open source embedded system board Arduino Uno with I2C protocol, which will perform some task like issuing the alarm notification and switching off the car power source to stop the car upon receiving the positive detection message from Raspberry-pi. Keywords— Drowsiness, alcoholic intoxication, Raspberry pi, Arduino UNO, Open CV, Embedded System, Python IDLE, Haar Cascade classifier, Linux, Raspbian, OV5647, MQ-3, I2C, relay, buzzer.

Parasitic effect compensation of defected ground structure and its application to design of bandpass filter

Abstract This study demonstrates the parasitic effect observed in the passband of a bandpass filter (BPF) using a defected ground structure (DGS). This parasitic effect has been compensated by employing step discontinuity in the microstrip feed line. By implementing this technique, the performance of a pseudocombline BPF of 5 GHz operating frequency and a fractional bandwidth of around 15% together with a DGS cell is improved. The filter provides less than −1 dB insertion loss in the operating frequency and a stop band attenuation of about −20 dB on average. When the final BPF structure is simulated, fabricated, and measured, good agreement is observed between the simulated and measured results. The BPF proposed is applicable in the wireless LAN and RADAR systems.

Low cost and efficient ECG measurement system using PIC18F4550 microcontroller

This paper demonstrates a simple, efficient and low cost ECG and heart beat measurement system using PIC18F4550 microcontroller. The design includes LT1028 OP AMP IC based signal conditioning unit. Detected ECG signal inside microcontroller is send to a Lab VIEW based GUI platform with USB CDC protocol and also tested with RS-232 protocol. Signal plotting and heart beat calculation is done inside LabVIEW program. ECG signal can also be viewed from PWM port of PIC18F4550 microcontroller via a low pass filtering stage. The whole design is simulated successfully with Proteus circuit simulator. The ECG signal is extracted in audio format (.WAV) from LabVIEW biomedicai toolkit for ECG simulator keeping 1.2 mV upper voltage limit and -0.4 mV lower voltage limit. The audio file is given as the input to the circuit in Proteus. USB simulation is done with the help of Proteus Virtual USB and Microchip USB CDC driver. RS-232 virtual serial port is created using Eltima virtual serial port software. MPLAB IDE is used as microcontroller program compiler.

Coplanar Waveguide UWB Bandpass Filter Using Defected Ground Structure and Interdigital Capacitor

In this present work, a coplanar waveguide (CPW) ultra-wideband (UWB) bandpass filter (BPF) is proposed using defected ground structure (DGS) and interdigital capacitor having the exact passband frequency range of (3.1–10.6) GHz, minimum passband insertion loss of 0.14 dB and stopband rejection level below 20 dB from 11.8 to 16 GHz. Lumped equivalent circuit model of CPW UWB BPF is also extracted. Mathematical modelling to calculate values of generated inductances, capacitances and resistance of proposed BPF is indicated. Circuit size is miniaturized to an area of 7 mm × 9.3 mm and BPF is simulated on Fr4 substrate with dielectric constant of 4.4 and thickness of 1.6 mm. The proposed BPF is applicable for Bluetooth and wireless devices.

A low-cost 4.9 GHz balanced bandpass filter with good common mode isolation

Abstract This paper presents a compact and low-cost balanced bandpass filter (BPF) operating at 4.9 GHz with high selectivity using mixed coupled ‘U’ shaped resonators, parallel coupled feed line, open and centrally loaded short circuited stubs, respectively. The odd–even mode decoupling scheme and the weakly coupled resonator concepts are utilized for the analysis and validation of differential mode (DM) and common mode (CM) equivalent circuits of the proposed BPF. The passband CM response of the balanced BPF is suppressed above 30 dB by employing grounded stubs in the symmetry plane, which converts the CM response to an all stop characteristic. The second harmonics generated by the BPF is also suppressed using open stubs located near the feed lines. The proposed balanced BPF is fabricated on an FR4 substrate (εr = 4.4, h = 1.6 mm, tan δ = 0.02), which provides 10.7% measured 3 dB fractional bandwidth (FBW) and minimum 1.2 dB insertion loss in the passband (4.7–5.2 GHz). A good agreement is found between the simulated and measured results.