Shipun Anuar Hamzah

GA-based QoS Route Selection Algorithm for Mobile Ad-Hoc Networks

The design of QoS routing protocol for mobile ad hoc networks is a challenging issue. In selecting the most optimal route from source to destination, one has to choose from a set of routes with the corresponding connectivity qualities. This paper describes the QoS routing scheme, that select a source-destination route using genetic algorithm (GA). The route need to satisfy the node bandwidth, node delay, end-to-end delay and node conectivity index. We described the GA operation including population initialization, fitness calculation, crossover process, mutation process and selection of GA parameters. Simulation experiments are performed for 20 mobile nodes to predict the basic performances of QoS routing algorithm in terms of the effect of mobility. The result shows that QoS routing can successfully utilized GA in finding the optimal route.

Size Reduction and Multiband Characteristic Using Koch Fractal Dipole

The Koch fractal dipole antenna is designed, simulated and fabricated for operating at 900MHz frequency band. By using Koch fractal antenna mathematic equation and some consideration, the desired resonant frequencies can be achieved. The designed antenna is started with developing microstrip dipole antenna for the same frequency operation. The size of Koch fractal dipole is reduced around 40% compactness compared to microstrip dipole. A multiband characteristic is investigated until third iteration with identication angle, thetas = 60deg trace width, W = 1mm and fabricate onto FR-4 substrate using SMA connector

Reduced Size Harmonic Suppressed Fractal Dipole Antenna with Integrated Reconfigurable Feature

The presence of harmonics are undesirable in many applications. Embedding fractal technology into an antenna makes it possible to reduce the physical size, increase its operating bandwidth and directivity. However, the technique can cause significant undesired harmonics problems associated with higher order modes of the antenna. This paper presents simulation and measurement work of a reduced size Koch fractal meander dipole antenna that has tunable capability of a reconfigurable operation within the observed range of 400Mhz to 3.5GHz. Each undesired harmonic is removed using one or two stubs. A microwave switch-able dipole antenna concept using Koch curve integrated with open circuit stubs is presented. The structure employed fractal technology that can eliminate higher order modes. With the utilization of Koch curves, the antenna size is reduced, but the number of higher order modes has proportionally increased. The size of the proposed antenna is small with regards to the operating frequency. The stub has improved the antenna performance.

Design Sierpinski Gasket Antenna for WLAN Application

This project mainly discussed on designing and fabricating the antenna using fractal concept to obtain the dual band resonant frequency at 2.4 GHz and 5.8 GHz for wireless local area network (WLAN) application. The application of fractal geometry can be used to miniaturize the antenna due to their self-similarity and this project focusing on designing the Sierpinski gasket antenna for first iteration. The antenna had been simulated using CST microwave studio, while the fabricated antenna had been tested using network analyzer. The results of both antenna simulation and measurement are in good agreement with the design expectation. The antenna was fabricated on printed circuit board (PCB) using epoxy/ glass (FR- 4) substrate with 30cm by 30cm metallic copper ground plane.

Design, Simulation, Fabrication and Measurement of a 900MHZ Koch Fractal Dipole Antenna

This paper present the design and fabrication of the Koch fractal dipole antenna. A multi-band element has been designed based on the Koch fractal which operates over two frequency band. The property of antennas such as return loss, S11 has been investigated at frequency of 900 MHz for GSM band. Wide bandwidth with input return loss of -10 dB has been achieved from 0 to 8 GHz using this fractal antenna. The size of fabricated antenna is reduced around 64% compare to conventional dipole antenna at these frequencies.

Analysis and receiving of downlink GSM signal using spectrum analyzer

Coverage prediction can help cellular radio operator to predict the service area that to be covered based on received radio field strength. However, the field measurement on the received radio signal strength is important and has to be carried out at a few locations. Receiving of cellular radio signal from a system operator including GSM (e.g. Maxis and Celcom) have been done by using spectrum analyzer around University of College Technology Tun Hussein Onn (KUiTTHO). This signal is then analyzed to determine the important parameters such as frequency, signal strength, channels, etc. In this work, we have developed a monopole antenna to receive the signal for indoor and outdoor locations.

Smart Home Security Access System Using Field Programmable Gate Arrays

Received Dec 04, 2017 Revised Jan 11, 2018 Accepted Apr 15, 2018 Wireless Body Area Networks (WBANs) are fundamental technology in health care that permits the information of a patient’s essential body parameters to be gathered by the sensors. However, the safety and concealment defense of the gathered information is a key uncertain problem. A Hybrid Key Management (HKM) scheme [13] is worked based on Public Key Cryptography (PKC)-authentication scheme. This scheme uses a oneway hash function to construct a Merkle Tree. The PKC method increase the computational complexity and lacking scalability. Additionally, it increases expensive computation, communication costs and delay. To overcome this problem, Robust Security for Protected Health Information by ECC with signature Hash Function in WBAN (RSP) is proposed. The system employs hash-chain based key signature technique to achieve efficient, secure transmission from sensor to user in WBAN. Moreover, Elliptical Curve Cryptography algorithm is used to verifies the authenticate sensor. In addition, it describes the experimental results of the proposed system demonstrate the efficient data communication in a network.A Weblogs contains the history of User Navigation Pattern while user accessing the websites. The user navigation pattern can be analyzed based on the previous user navigation that is stored in weblog. The weblog comprises of various entries like IP address, status code and number of bytes transferred, categories and time stamp. The user interest can be classified based on categories and attributes and it is helpful in identifying user behavior. The aim of the research is to identifying the interested user behavior and not interested user behavior based on classification. The process of identifying user interest, it consists of Modified Span Algorithm and Personalization Algorithm based on the classification algorithm user prediction can be analyzed. The research work explores to analyze user prediction behavior based on user personalization that is captured from weblogs.Wireless Body Area Networks (WBANs) are fundamental technology in health care that permits the information of a patient’s essential body parameters to be gathered by the sensors. However, the safety and concealment defense of the gathered information is a key uncertain problem. A Hybrid Key Management (HKM) scheme [13] is worked based on Public Key Cryptography (PKC)-authentication scheme. This scheme uses a oneway hash function to construct a Merkle Tree. The PKC method increase the computational complexity and lacking scalability. Additionally, it increases expensive computation, communication costs and delay. To overcome this problem, Robust Security for Protected Health Information by ECC with signature Hash Function in WBAN (RSP) is proposed. The system employs hash-chain based key signature technique to achieve efficient, secure transmission from sensor to user in WBAN. Moreover, Elliptical Curve Cryptography algorithm is used to verifies the authenticate sensor. In addition, it describes the experimental results of the proposed system demonstrate the efficient data communication in a network.

A study on the achievable data rate in massive MIMO system

The achievable high data rates depend on the ability of massive multi-input-multi-output (MIMO) for the fifth-generation (5G) cellular networks, where the massive MIMO systems can support very high energy and spectral efficiencies. A major challenge in mobile broadband networks is how to support the throughput in the future 5G, where the highlight of 5G expected to provide high speed internet for every user. The performance massive MIMO system increase with linear minimum mean square error (MMSE), zero forcing (ZF) and maximum ratio transmission (MRT) when the number of antennas increases to infinity, by deriving the closed-form approximation for achievable data rate expressions. Meanwhile, the high signal-to-noise ratio (SNR) can be mitigated by using MMSE, ZF and MRT, which are used to suppress the inter-cell interference signals between neighboring cells. The achievable sum rate for MMSE is improved based on the distributed users inside cell, mitigated the inter-cell interference caused when send the same signal by other cells. By contrast, MMSE is better than ZF in perfect channel state information (CSI) for approximately 20% of the achievable sum rate.The achievable high data rates depend on the ability of massive multi-input-multi-output (MIMO) for the fifth-generation (5G) cellular networks, where the massive MIMO systems can support very high energy and spectral efficiencies. A major challenge in mobile broadband networks is how to support the throughput in the future 5G, where the highlight of 5G expected to provide high speed internet for every user. The performance massive MIMO system increase with linear minimum mean square error (MMSE), zero forcing (ZF) and maximum ratio transmission (MRT) when the number of antennas increases to infinity, by deriving the closed-form approximation for achievable data rate expressions. Meanwhile, the high signal-to-noise ratio (SNR) can be mitigated by using MMSE, ZF and MRT, which are used to suppress the inter-cell interference signals between neighboring cells. The achievable sum rate for MMSE is improved based on the distributed users inside cell, mitigated the inter-cell interference caused when send the s...

Design and Analysis of Triple Band Inverted-H Antenna for DCS, WiMAX and WLAN Applications

In the rapid progress of commercial communication applications, the development of multiband antenna has an important role. In this paper, a triple band Inverted-H planar antenna for DCS1700, WiMAX2600 and WLAN3100 is presented. The proposed antenna was designed using commercially available CST software. Then, the designed antenna was fabricated on a FR4 substrate and tested using network and spectrum analyzers. The measured S11 results are -15.14 dB, -15.88 dB and -25.77 dB for the three operating frequency bands of 1.764 GHz, 2.739 GHz and 3.17 GHz respectively. The simulated results such as in S11 and radiation patterns have good agreement with the measurement results.

Sierpinski Carpet Fractal Antenna with Harmonic Suppression Capability

A harmonic suppressed fractal antenna suitable for energy harvesting system is presented. Sierpinski Carpet fractal antenna is designed and developed with the capability to eliminate the harmonics frequencies of the higher order modes. To accomplish this, three open circuit stubs as a stubs-filter have been integrated on the transmission feed line to suppress the frequency from 2 GHz to 5 GHz. This technique is suitable for developing antenna with harmonic suppression or for single band antennas. The antenna is designed on the FR-4 board with the size of 38 mm x 38 mm which operates efficiently at 1.8 GHz, suitable for wireless communication applications. The prototype can suppress undesired harmful harmonic frequencies presents at 3.6 GHz and 4.2 GHz with the observed range. The antenna has a good potential to be used for rectenna system with small size and better performance. Simulation and measurement results obtained are in good agreement, which have confirmed the design concept.