Sabbir Ahmed

Sabbir Ahmed


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
2 April 2018 in Journal of Intelligent & Robotic Systems
Verified
Journal Article
Closed access
PDF file
GPG. Pantelimon
G. Pantelimon
KTK. Tepe
K. Tepe
Rupp CarriveauRupp Carriveau
Rupp Carriveau
SASabbir Ahmed
Sabbir Ahmed

4 November 2020 in Applied Sciences
Verified
Journal Article
Open access
PDF file
Elvin Ugonna EziamaElvin Ugonna Eziama
Elvin Ugonna Eziama
Faroq AwinFaroq Awin
Faroq Awin
SASabbir Ahmed
Sabbir Ahmed
Luz  Marina Santos JaimesLuz Marina Santos Jaimes
Luz Marina Santos Jaimes
PAPelumi Akinyemi
Pelumi Akinyemi
Danilo Corral-De-WittDanilo Corral-De-Witt
Danilo Corral-De-Witt
Connected and automated vehicles (CAVs) as a part of Intelligent Transportation Systems (ITS) are projected to revolutionise the transportation industry, primarily by allowing real-time and seamless information exchange of vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I). However, these connectivity and automation are expected to offer vast numbers of benefits, new challenges in terms of safety, security and privacy also emerge. CAVs continue to rely heavily on their sensor readings, the input obtained from other vehicles and the road side units to inspect roadways. Consequently, anomalous reading of sensors triggered by malicious cyber attacks may lead to fatal consequences. Hence, like all other safety-critical applications, in CAVs also, reliable and secure information dissemination is of utmost importance. As a result, real time detection of anomaly along with identifying the source is a pre-requisite for mass deployment of CAVs. Motivated by this safety concerns in CAVs, we develop an efficient anomaly detection method through the combination of Bayesian deep learning (BDL) with discrete wavelet transform (DWT) to improve the safety and security in CAVs. In particular, DWT is used to smooth sensor reading of a CAV and then feed the data to a BDL module for analysis of the detection and identification of anomalous sensor behavior/data points caused by either malicious cyber attacks or faulty vehicle sensors. Our numerical experiments show that the proposed method demonstrates significant improvement in detection anomalies in terms of accuracy, sensitivity, precision, and F1-score evaluation metrics. For these metrics, the proposed method shows an average performance gain of 7.95%, 9%, 8.77% and 7.33%, respectively when compared with Convolutional Neural Network (CNN-1D), and when compared with BDL, the corresponding numbers are 5%, 7.9%, 7.54% and 4.1% respectively.

10 October 2019 in Applied Sciences
Verified
Journal Article
Open access
PDF file
Danilo Corral-De-WittDanilo Corral-De-Witt
Danilo Corral-De-Witt
SASabbir Ahmed
Sabbir Ahmed
Faroq AwinFaroq Awin
Faroq Awin
José-Luis Rojo-ÁlvarezJosé-Luis Rojo-Álvarez
José-Luis Rojo-Álvarez
KTKemal Tepe
Kemal Tepe
Television White Spaces (TVWS)-based cognitive radio systems can improve spectrum efficiency by facilitating opportunistic usage of television broadcasting spectrum by secondary users without interfering with primary users. Previously applied models introduce missed detection errors, giving a limited estimation of the spectrum occupancy, which does not correspond to the reality of its usage, hence resulting in a partial waste of this resource. Considering jointly parameters like false alarm probability and detection probability, this article proposes a probabilistic model that can identify TVWS with improved accuracy. The proposed model considers energy detection criteria, combined with simultaneous sensing of the noise and of the signal from primary users. In order to demonstrate the model effectiveness, a low-cost Mobile Spectrum Sensing Station prototype was designed, implemented, and subsequently mounted on a vehicle. More than eight million spatio-temporally variant data samples were collected by scanning the UHF-TV spectrum of 500–698 MHz in the city of Windsor, ON, Canada. Analysis of the collected data showed that the proposed model achieves an accuracy improvement of about 9.6% compared to existing models, demonstrating that TVWS vary with spatial displacement and increasing significantly in the rural areas. Even in the most crowded spectrum zone, about 28% of the channels are identified as TVWS, and this number increases to a maximum of 60% in less crowded regions in urban areas. We conclude that the proposed model improves the TVWS detection compared with other used models, and also that the elements considered in this research contribute to reduce the complexity of the mathematical calculations while maintaining the accuracy. A low-cost open-source sensing station has been designed and tested, which represents an operative and useful data source in this setting.

29 September 2020 in Telecom
Verified
Journal Article
Open access
PDF file
Danilo Corral-De-WittDanilo Corral-De-Witt
Danilo Corral-De-Witt
SASabbir Ahmed
Sabbir Ahmed
José-Luis Rojo-ÁlvarezJosé-Luis Rojo-Álvarez
José-Luis Rojo-Álvarez
KTKemal Tepe
Kemal Tepe
The current demand for a wireless electromagnetic spectrum is higher than ever before due to rapid technological development in the field of information and communication technologies that has resulted in monumental growth in data-centric services. The usage of idle TV channels in the Television Ultra High Frequencies (TV-UHF) band (500–698 MHz), also known as Television White Spaces (TVWS), is a relatively new and promising concept for wireless connectivity that can be used to cater to the demand. A challenge in this setting is to figure out a fast and cost-effective method of TVWS presence estimation, such as the use of open hardware and software tools, reducing sensing time. This article proposes a Rapid Estimation Method (REM) for TVWS estimation that uses the statistical information of the sensed signals. Our probabilistic approach analyzes the collected parameters of more than eight million data samples taken by scanning the TV-UHF spectrum in the city of Windsor, ON, Canada. The calculated statistical parameters and a group of auxiliary parameters were combined to estimate rapidly the amount of TVWS available in the sensed locations. By applying the proposed rapid estimation method, the presence of TVWS was identified and verified with an accuracy of about 76% according to the results obtained, the average variation when comparing the calculated and detected probabilities of TVWS was in a range of 15%, and the method could be a viable solution to the spectrum need.