• Design of band-notched ultra wideband antenna for indoor and wearable wireless communications

      Ur-Rehman, Masood; Abbasi, Qammer Hussain; Akram, Muhammad; Parini, Clive G.; University of Bedfordshire; Texas A & M University at Qatar; University of Engineering and Technology, Pakistan; Queen Mary University of London (Institution of Engineering and Technology, 2014-10-16)
      Design of a tapered-slot ultra wideband (UWB) band-notched wearable antenna is presented in this study. The antenna operation covers the whole UWB frequency spectrum of 7.5 GHz ranging from 3.1 to 10.6 GHz, while rejecting the wireless local area network operation at 5.25 GHz band. The performance of the antenna is analysed through simulations and validated through measurements. The antenna makes use of ultra-thin liquid crystal polymer (LCP) substrate. The presented return loss and radiation pattern results show that the antenna offers excellent performance in the UWB frequency band in free space. Use of the LCP substrate makes the antenna to efficiently mitigate the bending effects. Moreover, the antenna performs well in on-body configurations and its working is little affected in adversely hot and humid weather conditions. Furthermore, it offers good on-body communication link and pulse fidelity. These features make the proposed antenna design a well-suited choice for hand-held and wearable UWB applications.
    • Double threshold authentication using body area radio channel characteristics

      Zhao, Nan; Ren, Aifeng; Hu, Fangming; Zhang, Zhiya; Ur-Rehman, Masood; Zhu, Tianqiao; Yang, Xiaodong; Alomainy, Akram; Xidian University, China; University of Bedfordshire; et al. (Institute of Electrical and Electronics Engineers Inc., 2016-06-06)
      The demand of portable and body-worn devices for remote health monitoring is ever increasing. One of the major challenges caused by this influx of wireless body area network (WBAN) devices is security of user's extremely vital and personal information. Conventional authentication techniques implemented at upper layers of the Open System Interconnection (OSI) model usually consumes huge amount of power. They also require significant changes at hardware and software levels. It makes them unsuitable for inherently low powered WBAN devices. This letter investigates the usability of a double threshold algorithm as a physical layer security measure in these scenarios. The algorithm is based on the user's behavioral fingerprint extracted from the radio channel characteristics. Effectiveness of this technique is established through experimental measurements considering a variety of common usage scenarios. The results show that this method provides high level of security against false authentication attacks and has great potential in WBANs.
    • Enhancing cell-edge performance using multi-layer soft frequency reuse scheme

      Hossain, Md. S.; Tariq, Faisal; Safdar, Ghazanfar Ali; Radio Access Group, Bangladesh; Queen Mary University of London; University of Bedfordshire (Institution of Engineering and Technology, 2015-10-29)
      In cellular systems, maintaining data rate at the cell edge has been a challenging task due to strong co-channel interference from neighbouring cells. Several techniques have been proposed to tackle the issue, among which soft frequency reuse (SFR) is the most widely used. A novel multi-layer SFR scheme combined with cell sectoring is proposed to improve the performance in cell-edge region. Then, a spectrum allocation scheme in a three-cell reuse system is designed to ensure the maximisation of the efficiency. A generic expression for power allocation in different regions along with the signal-to-noise ratio of multi-layer SFR in sectored cell is derived. Finally, systemlevel simulation has been carried out to demonstrate the efficiency of the proposed resource allocation scheme. It is shown that the spectral efficiency at cell-edge area improves by ∼10% which is significant for the cell-edge region.
    • IEEE Access special section: advances in interference mitigation techniques for device-to-device communications

      Ur-Rehman, Masood; Gao, Yue; Chaudhry, Mohammad Asad Rehman; Safdar, Ghazanfar Ali; Xu, Yanli; University of Essex; Queen Mary University of London; University of Toronto; University of Bedfordshire; Shanghai Maritime University (IEEE, 2019-12-17)
    • Monitoring of patients suffering from REM sleep behavior disorder

      Yang, Xiaodong; Shah, Syed Aziz; Ren, Aifeng; Zhao, Nan; Zhao, Jianxun; Hu, Fangming; Zhang, Zhiya; Zhao, Wei; Ur-Rehman, Masood; Alomainy, Akram; et al. (Institute of Electrical and Electronics Engineers Inc., 2018-04-16)
      Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia that involves involuntary, unwanted, and random movements of a dreaming patient. Typically, these dreams contain violent activities. There is a high likelihood of the patient being injured or hurting his bed-partner as a result of these enactments. Continuous monitoring of sleeping RBD patients can prevent these harmful events through timely intervention. This paper presents a novel method for continuous observation of RBD patients exploiting fine-grained amplitude and phase information of the wireless channel response. The variations in the wireless channel response as a result of different patient movements are assessed and used to identify RBD episodes. The data obtained are classified using a support vector machine and deliver an accuracy level of more than 90%. To the best of authors' knowledge, this is a first attempt at using radio frequency signals to sense RBD in real time.
    • A real-time monthly DR price system for the smart energy grid

      Mahmud, ASM Ashraf; Sant, Paul; Tariq, Faisal; Jazani, David; University of Bedfordshire; Queen Mary University of London (European Alliance for Innovation, 2017-08-03)
      The smart grid is the next generation bidirectional modern grid. Energy users' are keen on reducing their bill and energy suppliers are also keen on reducing their industrial cost. Our demand response model would benefit them both. We have tested our model with the UK based traditional price value using a real-time basis. Energy users significantly reduced their bill and energy suppliers reduced their industrial cost due to load shifting. The Price Control Unit (PCU) and Price Suggestions Unit (PSU) utilise and embedded algorithms to vary price based upon demand. Our model makes suggestions based on energy threshold and makes use of stochastic approximation methods to produce prices. Our results shows that bill and peak load reductions benefit both the energy provider and users. This model also addresses users' preferences, if users are non-responsive, they can still reduce their bills.
    • The road ahead for body-centric wireless communication and networks

      Ur-Rehman, Masood; Abbasi, Qammer Hussain; Alomainy, Akram; University of Bedfordshire; Texas A & M University at Qatar; University of Engineering and Technology, Pakistan; Queen Mary University of London (Institution of Engineering and Technology, 2015-02-26)
      Wireless interaction of the human user with the computing devices has seen a profound growth in the past decade. Wearable technology has successfully moved past the adoption stage and now stands at the brink of massive diversification with an explosion in popularity and applicability. The estimated market value of the wearable technology is expected to hit $32 billion mark by 2020 [1, 2]. It would cause the global wearable devices market it to grow from 20 million device shipments in 2015 to 187.2 million units annually by 2020 [3].
    • Threshold power based UE admittance and contention free resource allocation for interference mitigation in cognitive femtocells

      Safdar, Ghazanfar Ali; Tariq, Faisal; Kpojime, Harold Orduen; University of Bedfordshire; Queen Mary University of London (Springer, 2017-11-17)
      Femtocells are aimed at providing strong coverage in the indoor area where typical macrocell coverage is very poor. It has hugely attracted network operators and stakeholders mainly due to its simple plug and play operation and low cost. Femtocells operate on a much lower power compared to macrocell and thus provide a number of benefits including energy efficiency and frequent spatial reuse of the spectrum. Femtocells are overlaid on macrocells and designed to co-exist with them sharing the same spectrum pool. However, since they are deployed by the end user, no pre-deployment resource planning is possible. So, interference among the femtocells as well as between femtocells and macrocells remain a major bottleneck for successful operation of femtocell networks. This paper proposes a novel threshold power based admittance and contention free resource allocation for interference mitigation in cognitive femtocell networks. In our proposed scheme, a Femtocell Access Point with Cognitive radio capability known as Cognitive Femtocells (CF), sets a threshold value on the mutual interference between itself and a close by macrocell user equipment (MUE). To mitigate cross-tier interference, a CF classifies MUEs with higher than threshold interference value as Undesirable MUEs (UMUEs) and subsequently admits it as one of its user equipment. MUEs with lower than threshold interference values are classified as Desirable MUEs (DMUEs). To mitigate co-tier interference, proposed scheme introduces a scheduling engine which employs matching policy attributes and assigns resource blocks (RBs) of unique DMUEs to CFs to avoid any possible contention problems, thus providing improved co-tier interference. System level simulations have been performed to demonstrate effectiveness of scheme and significant performance improvement in terms of SINR, throughput and spectrum efficiency.