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Throughput and delay limits of chirp spread spectrum‐based IEEE 802.15.4a
Ullah, Niamat,Sanaullah Chowdhury, M.,Khan, Pervez,Ullah, Sana,Kwak, Kyung Sup Wiley 2012 International Journal of Communication Systems Vol. No.
<P><B>SUMMARY</B></P><P>The IEEE 802.15.4 standard is designed to provide a low‐power, low data rate protocol offering a high reliability. As an amendment to this standard, IEEE 802.15.4a introduces new options for physical layer to enable precision ranging. In this work, we analyzed the theoretical throughput and delay bounds of the unslotted version of chirp spread spectrum PHY‐based 802.15.4a. The formulae for transmission between one sender and one receiver for an ideal channel with no transmission errors are given. The throughput and delay bounds are derived for different frequency bands and data rates. Additionally, to measure spectral utilization, we measured the bandwidth efficiency for both the standards. We also compared our results with IEEE 802.15.4. The comparative analysis concludes that the performance of 802.15.4a exceeds 802.15.4 in terms of throughput and delay. The analytical results of throughput are verified by computer simulations. Copyright © 2011 John Wiley & Sons, Ltd.</P>
Niamat Ullah Ibne Hossain,Morteza Nagahi,Raed Jaradat,Chiranjibi Shah,Randy Buchanan,Michael Hamilton 한국CDE학회 2020 Journal of computational design and engineering Vol.7 No.3
Due to the widespread of new technologies, the modern electric power system has become much more complex and uncertain. The Integration of technologies in the electric power system has increased the exposure of cyber threats and correlative susceptibilities from malicious cyber-attacks. To better address these cyber risks and minimize the effects of the power system outage, this research identifies the potential causes and mitigation techniques for the smart grid (SG) and assesses the overall cyber resilience of smart grid systems using a Bayesian network approach. Bayesian network is a powerful analytical tool predominantly used in risk, reliability, and resilience assessment under uncertainty. The quantification of the model is examined, and the results are analyzed through different advanced techniques such as predictive inference reasoning and sensitivity analysis. Different scenarios have been developed and analyzed to identify critical variables that are susceptible to the cyber resilience of a smart grid system of systems. Insight drawn from these analyses suggests that overall cyber resilience of the SG system of systems is dependent upon the status of identified factors, and more attention should be directed towards developing the countermeasures against access domain vulnerability. The research also shows the efficacy of a Bayesian network to assess and enhance the overall cyber resilience of the smart grid system of systems.
Ullah, Sana,Saleem, Shahnaz,Higgins, Henry,Ullah, Niamat,Zhong, Yingji,Kwak, Kyung Sup Hindawi Publishing Corporation 2010 Eurasip Journal on Wireless Communications and Net Vol.2010 No.-
<P>The performance of the implant inside a human body with polarisation, distance, and different power settings at the base-station is presented. In addition, the unslotted CSMA/CA protocol is studied for a heterogeneous WBAN.</P>
WBAN MAC Protocols― Non-Saturation Modeling and Performance Analysis
( Pervez Khan ),( Niamat Ullah ),( Hoon Kim ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.3
The current literature on discrete-time Markov chain (DTMC) based analysis of IEEE 802.15.6 MAC protocols for wireless body area networks (WBANs), do not consider the ACK timeout state, wherein the colliding nodes check the ill fate of their transmissions, while other contending nodes perform backoff check that slot as usual. In this paper, our DTMC model accurately captures the carrier sense multiple access with collision avoidance (CSMA/CA) mechanism of IEEE 802.15.6 medium access control (MAC) and allows the contending nodes performing backoff to utilize the ACK timeout slot during collisions. The compared rigorous results are obtained by considering a non-ideal channel in non-saturation conditions, and CSMA/CA parameters pertaining to UWB PHY of IEEE 802.15.6 MAC protocols.
WBAN MAC Protocols- Non-Saturation Modeling and Performance Analysis
Khan, Pervez,Ullah, Niamat,Kim, Hoon Korean Society for Internet Information 2017 KSII Transactions on Internet and Information Syst Vol.11 No.3
The current literature on discrete-time Markov chain (DTMC) based analysis of IEEE 802.15.6 MAC protocols for wireless body area networks (WBANs), do not consider the ACK timeout state, wherein the colliding nodes check the ill fate of their transmissions, while other contending nodes perform backoff check that slot as usual. In this paper, our DTMC model accurately captures the carrier sense multiple access with collision avoidance (CSMA/CA) mechanism of IEEE 802.15.6 medium access control (MAC) and allows the contending nodes performing backoff to utilize the ACK timeout slot during collisions. The compared rigorous results are obtained by considering a non-ideal channel in non-saturation conditions, and CSMA/CA parameters pertaining to UWB PHY of IEEE 802.15.6 MAC protocols.
Performance Analysis of WBAN MAC Protocol under Different Access Periods
Khan, Pervez,Ullah, Niamat,Alam, Md. Nasre,Kwak, Kyung Sup SAGE Publications 2015 International journal of distributed sensor networ Vol.2015 No.-
<P>The IEEE 802.15.6 is a new standard on wireless body area network (WBAN) for short-range, extremely low power wireless communication with high data rates in the vicinity of, or inside, a human body. The standard defines two contention-based channel access schemes: slotted ALOHA and carrier sense multiple access with collision avoidance (CSMA/CA) using an alternative binary exponential backoff procedure. The standard supports quality of service (QoS) differentiation through user priorities and access phases. In this study, we develop an analytical model for the estimation of performance metrics such as energy consumption, normalized throughput, and mean frame service time, employing a Markov chain model under nonsaturated heterogeneous traffic scenarios including different access phases specified in the standard for different user priorities and access methods. We conclude that the deployment of exclusive access phase (EAP) is not necessary in a typical WBAN using CSMA/CA because it degrades the overall system throughput, consumes more energy per packet, and results in higher delay for nonemergency nodes.</P>
Azeem Umair,Younis Hannan,ullah Niamat,Mehboob Khurram,Ajaz Muhammad,Ali Mushtaq,Hidayat Abdullah,Muhammad Wazir 한국원자력학회 2024 Nuclear Engineering and Technology Vol.56 No.1
This study focuses on measuring the levels of naturally occurring radioactivity in the soil of Swabi, Khyber Pakhtunkhwa, Pakistan, as well as the associated health hazard. Thirty (30) soil samples were collected from various locations and analyzed for 226Ra, 232Th, and 40K radioactivity levels using a High Purity Germanium detector (HPGe) gamma-ray spectrometer with a photo-peak efficiency of approximately 52.3%. The average values obtained for these radionuclides are 35.6 ± 5.7 Bqkg 1, 47 ± 12.5 Bqkg 1, and 877 ± 153 Bqkg 1, respectively. The level of 232Th is slightly higher and 40K is 2.2 times higher than the internationally recommended limit of 30 Bqkg 1 and 400 Bqkg 1, respectively. Various parameters were calculated based on the results obtained, including Radium Equivalent (Raeq), External Hazard (Hex), Absorbed Dose Rate (D), Annual Gonadal Equivalent Dose (AGDE), Annual Effective Dose Rate, and Excess Lifetime Cancer Risk (ELCR), which are 170.3 ± 24 Bqkg 1, 0.46 ± 0.06 Bqkg 1, 81.4 ± 2.04 nGy h 1, 582 ± 78.08 μSvy 1, 99.8 ± 13.5 μSv Gy 1, and 0.349 ± 0.04, respectively. These values are below the limits recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) in 2002. This study highlights the potential radiation threats associated with natural radioactivity levels in the soil of Swabi and provides valuable information for public health and safety
Framed slotted aloha based MAC protocol for low energy critical infrastructure monitoring networks
Sanaullah Chowdhury, M.,Ullah, Niamat,Ameen, Mosaddique Al,Kwak, Kyung Sup John Wiley Sons, Ltd 2014 International Journal of Communication Systems Vol.27 No.10
<P><B>SUMMARY</B></P><P>Recently, the IEEE TG4k has been formed to amend the IEEE 802.15 family to address the low energy critical infrastructure monitoring networks. The purpose is to facilitate point to multi‐thousands of point communication to collect the scheduled and event data from a large number of nonmains powered endpoints that are widely dispersed. It should support low energy operation, which is necessary for multiyear battery life. Other major features are application data rate up to 40 Kb/s, thousands of endpoints per mains powered infrastructure, asymmetric application data flow, small and infrequent messages, tolerant to data latency, etc. In this paper, we present a discussion on low energy critical infrastructure monitoring networks. We propose a medium access control protocol based on framed slotted aloha for these networks. We investigated probable packet sizes, energy consumptions, battery lifetime and the success rate for our protocol. The proposed protocol is simple to implement. Simulation results show that it is efficient in terms of packet success rate, energy consumption, and battery lifetime.Copyright © 2012 John Wiley & Sons, Ltd.</P>