Mohamad Yusoff Alias

Learn More
In mobile wireless sensor networks (WSN) coverage can be enhanced by moving the sensors so that a better arrangement is achieved. However, movement is a high energy consumption task. Therefore, in this paper besides coverage, the cost of moving the sensors is also taken into account. Both objectives are tackled in separate phases with coverage maximization(More)
Unlike a conventional wired network, a wireless network system is susceptible to attacks from malicious parties without the need to physically be present near the network entities or its equipments. With a large coverage area serving up to 50km in distance, the IEEE802.16 broadband wireless access (BWA) standard was designed from the ground up with security(More)
The family of minimum bit error rate (MBER) multiuser detectors (MUD) is capable of outperforming the classic minimum mean-squared error (MMSE) MUD in terms of the achievable bit-error rate (BER) owing to directly minimizing the BER cost function. In this paper, we will invoke genetic algorithms (GAs) for finding the optimum weight vectors of the MBER MUD(More)
Data offloading is a method to significantly improve network capacity. Offloading of data from macro-cells to pico-cells helps to ease capacity demand in hotspot areas where user distribution is dense and often demanding high bandwidths per user. This study uses a heterogeneous network using combined Long Term Evolution - WiFi IEEE 802.11n coverage to(More)
In this paper, we proposed a novel opportunistic spectrum aware routing in cognitive radio wireless mesh network (CRWMN) which allows the CR users effectively occupy the spectrum band depends on the spectrum availability and also perform dynamically channel switching for performance optimization. In a CRWMN, primary hidden node (PHN) and primary exposed(More)
Space-time block coded OFDM is capable of achieving substantial diversity gains, while supporting high bit-rates in wireless communications. By concatenating a space-time block coded OFDM scheme with powerful channel codes, the performance of the system can be further enhanced. In this contribution both Low-Density Parity-Check (LDPC) coding and turbo(More)
Vehicular communications are important to ensure emergency messages are transmitted on time to prevent accidents. Therefore, in recent years, various standardization bodies and automobile companies have developed vehicular ad hoc network (VANET) to ensure public road safety. The current IEEE802.11p schemes utilize only traffic type to categorize priority(More)
Voice over Internet Protocol (VoIP) services are susceptible to Internet Protocol (IP) network burstiness causing packets drop and momentary gap in the call. The main objective of this paper is to study the effect of various voice codec schemes on the VoIP Quality of Service (QoS). Popular voice codecs such as G.711, G.729A Conjugate-Structure(More)
This paper introduces a novel simulation testbed for investigating WLAN indoor localization systems. This testbed referred to as WiLocSim consists of a novel beacon received signal strength (RSS) simulator which provides realistic modeling of beacon signal characteristics such as multipath propagation, measurement noise and body loss. Each component of the(More)
Optical Orthogonal Frequency Division Multiplexing (O-OFDM) provides major advantages in mitigating Group-Velocity Dispersion (GVD) in Single Mode Fiber (SMF). Unfortunately, when the uncompensated long-haul transmission ranges become very large, substantial dispersion is accumulated. Owing to the large accumulated dispersion, the Cyclic Prefix (CP)(More)