Ghulam Ishaq Khan Institute of Engineering Sciences and Technology

About: Ghulam Ishaq Khan Institute of Engineering Sciences and Technology is a education organization based out in Topi, Pakistan. It is known for research contribution in the topics: Thin film & Quantum efficiency. The organization has 618 authors who have published 940 publications receiving 10674 citations.

Electromagnetic fields in a circular waveguide with D'B'-boundary conditions internally coated with chiral-nihility medium

Abstract: The present study deals with the propagation of electromagnetic fields and power in a circular waveguide, with D'B'- boundary conditions, internally coated with chiral-nihility medium. The electromagnetic fields inside the two layer circular waveguide defined by D'B'-boundary conditions, with one layer containing free space while other layer containing chiral- nihility medium, is investigated. D'B'-boundary conditions require vanishing of derivatives of the normal field components of D and B vectors, hence named as D'B'-boundary conditions. It has been investigated that unlike to the chiral-nihility coated perfect electromagnetic conductor (PEC) waveguide, there is a non-zero power transfer in chiral-nihility region in waveguide with D'B' boundary conditions.

Shock-proof and supple multiplex sensor based on Silicon composite fabricated through an energy-free technology

Abstract: Smart multi-purpose electronic devices are the utmost demanding products for sports, medical, and personal supervision. In smart appliances, silicon (Si) is one of the most common and widely utilized materials with remarkable properties in electronics. Still, the challenge is to exploit it for intelligent and innovative multi-functional applications under changing climate conditions. In this work, we proposed an all-in-one shock-proof and vibration-free smart, flexible multiplex, i.e., optical, thermal, compression, and stress sensor fabricated through energy-free rubbing-in technology. The p-type Si composite with carbon nanotubes (CNTs) and rubber acts as the device's active layer. The CNTs help to boost the conductivity of Si and rubber aid to enhance the flexibility as well as made the device shock and vibration-proof. Eventually, such multi-purpose devices are extremely encouraging for future smart wearable gadgets of the next generation not only due to their small size but also due to their cost-effectiveness.

MMSE equalization for discrete wavelet packet based OFDM

Abstract: In Orthogonal Frequency Division Multiplexing (OFDM), Fourier Transform (FT) is used as a modulation technique. To avoid Inter-symbol Interference (ISI) in OFDM by a time dispersive channel, a Cyclic Prefix (CP) is used which also reduces its spectral efficiency. Wavelet Packet Transform (WPT) as a modulation scheme has been proposed for wireless communication. In this paper, WPT based OFDM is presented and proposed using Minimum Mean Square Error (MMSE) equalizer. Equalization is a major factor in wavelets. MMSE is proposed for Wavelet based OFDM (WOFDM) based on WPT and compared with Zero Forcing Equalizer (ZFE). The performance is measured for arbitrary magnitude Finite Impulse Response (FIR) channels in the presence of Additive White Gaussian Noise (AWGN) and impulse noise. Simulation results show a clear improvement in Bit Error Rate (BER) for MMSE over ZFE equalization technique in the presence of noise.