• A comprehensive study for indoor localization techniques using received signal strength

      Obeidat, Huthaifa A.N.; Abd-Alhameed, Raed A.; Elkhazmi, Elmahdi A.; Asif, Rameez; Usman, Muhammad; See, Chan H.; Elmegri, Fauzi; Ghazaany, Tahereh S.; Zhu, Shaozhen (Sharon); Noras, James M.; et al. (2013)
    • Design considerations of MIMO antennas for mobile phones

      Usman, Muhammad; Abd-Alhameed, Raed A.; Excell, Peter S. (2008)
      The paper presents a new modeling and design concept of antennas using polar- ization diversity of 2 £ 2 and 3 £ 3 Multiple Input Multiple Outputs (MIMO) system that is proposed for future mobile handsets. The channel capacity is investigated and discussed over Raleigh fading channel and compared to a linear/planner antenna array MIMO channel. The capacity is also discussed over three types of power azimuth spectrums. The results are compared to the constraints capacity limits in which the maximum capacity observed.
    • Evaluation of the angle of arrival based techniques

      Asif, Rameez; Usman, Muhammad; Ghazaany, Tahereh S.; Hussaini, Abubakar S.; Abd-Alhameed, Raed A.; Jones, Steven M.R.; Noras, James M.; Rodriguez, Jonathan (2013)
      In this work we present the angle of arrival estimation techniques and their comparison at different values of SNR using a 5 element UCA. The techniques that have been considered include phase interferometry, Multiple Signal Classification and covariance. The results show that for very low values of SNR the performance of the covariance matrix based algorithm is the best but for slightly higher values of SNR, MUSIC algorithm outperforms covariance.
    • Initial analysis of k-factor in the Gulf region

      AbouAlmal, A.; Usman, Muhammad; Abd-Alhameed, Raed A.; Al-Ahmad, Hussain; Jones, Steven M.R.; Excell, Peter S. (2013)
      This paper investigates the seasonal variations of effective earth radius factor, k, in the Arabian Gulf region where non-standard propagation phenomena are commonly experienced. The k-factor is derived from the vertical profile of refractivity in the area under study. The vertical refractivity gradient, δN, in the first kilometre of the atmosphere above the ground surface is analysed using long term meteorological data. Long-term radiosonde data gathered in the United Arab Emirates (UAE), are used to calculate the variations of refractivity gradient and k-factor parameter.
    • Investigation of harmonic rejection for triangular patch microstrip antenna

      Bin-Melha, Mohammed S.; Jan, Naeem A.; Usman, Muhammad; Elmegri, Fauzi; See, Chan H.; Abd-Alhameed, Raed A.; Excell, Peter S. (2013)
      A coplanar edge-fed triangular patch antenna with an integrated stubline is proposed for harmonic rejection application. The design is aimed to achieve a good impedance matching to 50 ω at the fundamental frequency while suppressing radiation of the first and second harmonics. The antenna is attended to operate around 1GHz, with acceptable power gain above 1dBi and less than -15dBi at the harmonics. Simulated and measured results show a reasonable agreement.
    • Liquid level monitoring using passive RFID tags

      Atojoko, Achimugu A.; Bin-Melha, Mohammed S.; Elkhazmi, Elmahdi A.; Usman, Muhammad; Abd-Alhameed, Raed A.; See, Chan H. (2013)
      Tank flooding have become major causes of pollution both in residential and industrial areas majorly caused by overflows of water(mostly residential) and volatile poisonous industrial liquids from the storage tanks. An effective way of avoiding this problem will be by deploying some mechanism to monitor liquid level at each point in time and escalating unusual liquid levelsto a pump control circuit or to the relevant authorities for prompt action to avoid a flooding occurrence. This paper presents a low cost power efficient liquid level monitoring technique. Passive RFID tags are designed modelled and deployed, the signal variation from the Alien Reader Software are used to effectively estimate the level of liquid in any surface or underground tank. The experimental set up is presented and an expository presentation is made of the passive tag design, modelled and simulated and adopted for same application.