Qasim Awais

4G: The future mobile technology

With the rapid growth of user demands, and the limitations of third generation (3G) mobile communication systems, it is expected that fourth generation (4G) mobile systems are likely to reach the consumer market in another 4-5 years. 4G systems are expected to become a platform capable of providing increased bandwidth, higher data rates, and greater interoperability across communication protocols, and user friendly, innovative, and secure applications. This system will primarily focus on seamlessly integrating the existing systems like GSM, wireless LAN, and Bluetooth. This paper describes modulation scheme, different technologies, and network architectures that support 4G mobile systems. Challenges and some applications will also be presented. At last recommendations will be followed by conclusion.

Broadband and three-dimensional vibration energy harvesting by a non-linear magnetoelectric generator

Vibration, widely existing in an ambient environment with a variety of forms and wide-range of scales, recently becomes an attractive target for energy harvesting. However, its time-varying directions and frequencies render a lack of effective energy technology to scavenge it. Here, we report a rationally designed nonlinear magnetoelectric generator for broadband and multi-directional vibration energy harvesting. By using a stabilized three-dimensional (3D) magnetic interaction and spring force, the device working bandwidth was largely broadened, which was demonstrated both experimentally and theoretically. The multidirectional vibration energy harvesting was enabled by three identical suspended springs with equal intersection angles, which are all connected to a cylindrical magnet. Numerical simulations and experimental results show that the nonlinear harvester can sustain large-amplitude oscillations over a wide frequency range, and it can generate power efficiently in an arbitrary direction. Moreover, ...

A Novel Dual Ultrawideband CPW-Fed Printed Antenna for Internet of Things (IoT) Applications

This paper presents a dual-band coplanar waveguide (CPW) fed printed antenna with rectangular shape design blocks having ultrawideband characteristics, proposed and implemented on an FR4 substrate. The size of the proposed antenna is just 25 mm × 35 mm. A novel rounded corners technique is used to enhance not only the impedance bandwidth but also the gain of the antenna. The proposed antenna design covers two ultrawide bands which include 1.1–2.7 GHz and 3.15–3.65 GHz, thus covering 2.4 GHz Bluetooth/Wi-Fi band and most of the bands of 3G, 4G, and a future expected 5G band, that is, 3.4–3.6 GHz. Being a very low-profile antenna makes it very suitable for the future 5G Internet of Things (IoT) portable applications. A step-by-step design process is carried out to obtain an optimized design for good impedance matching in the two bands. The current densities and the reflection coefficients at different stages of the design process are plotted and discussed to get a good insight into the final proposed antenna design. This antenna exhibits stable radiation patterns on both planes, having low cross polarization and low back lobes with a maximum gain of 8.9 dB. The measurements are found to be in good accordance with the simulated results.

Traffic Engineering Using Multi-protocol Label Switching (MPLS) for Delay Sensitive Traffic

Traffic engineering is one of the most challenging topics in Multi-protocol Label switching (MPLS) which deal with controlling traffic in such a way so that optimized path can be achieved with respect to network utilization and efficient data delivery. Internet traffic use Interior Gateway Protocol (IGP) to send traffic over the network using the shortest path, Which causes the problem of the overlapping, the links, traffic congestion and traffic from the source to destination can exceed the traffic capability to send the data to a destination and media will be stuck. In this paper, we propose design and simulation of network, which will enable the traffic-engineering concept using IGP for delay sensitive traffic. We also propose a model, which performs better for delay sensitive traffic using MPLS. Our proposed solution is validated using OPNET, which is a network simulation tool, the results shows that delay sensitive traffic can be handled proactively while using MPLS.

Cognitive Access Point to Handle Delay Sensitive Traffic in WLANs

Over the last few years, the widespread use of wireless local area networks (WLANs) continues to gain more and more impetus. Due to the increase in variety of multimedia applications such as voice, video and gaming traffic, it is paramount to develop a mechanism for the quality of service (QoS) to support different types of traffic in WLAN. IEEE 802.11e was introduced to handle delay sensitive traffic using Enhance Distributed Coordination Function (EDCF) which is an extension of Distributed Coordination Function (DCF) to categorize traffic in different groups e.g. Real time and non real time traffic. In this paper, We investigate the impact of traffic handling techniques as part of medium access control (MAC) on the performance of WLAN. Firstly, we propose MAC level parameters settings, which are found the most suitable to WLAN in comparison with DCF and EDCF and then we propose a cognitive access point (CAP) which is based on novel approaches to assign proprieties on station level using the proposed algorithm and embedded Packet fragmentation technique in the Revised MAC parameters in cognitive access point mechanism. The benefits of the proposed approach is validated via experimental results using OPNET Modeler 17.5.

Hybrid WLAN Markov Chain to Handle TCP and UDP Traffic

In the Modern Era of computing, The Wireless communication has gained popularity with the passage of time due to unique features, e.g. Flexibility, cost effective and easy to configure as compare to traditional wired networks. Since 1990swireless networks become the backbone of every network and there are lots of concerns in wireless communication, which are needed to address to achieve effectiveness and productivity. Allot of organization switches from a wired network to wireless network due to its simple and cost effective solution. IEEE defines wireless standards and continues improvements are done with the passage of time to overcome deficiencies. In this paper, we perform an analysis of TCP and UDP traffic in WLANs, we proposed a hybrid WLAN Markov chain to increase the efficiency of the back off windows scheme. The results are validated using OPNET Modeler, which shows that the proposed back off windows scheme perform better as compare to default backoff windows scheme.