Muhammad Mahtab Alam

• PhD in Signal Processing and Telecommunication
• Professor at Tallinn University of Technology

In this paper accurate mobility and radio link modeling for intra-body communication is presented. The proposed enhanced mobility and radio link models introduce space and time variations to existing IEEE 802.15.6 channel models which can be used for better performance evaluation of new and existing algorithms and protocols. The contributions of th...

In this survey a new application paradigm life and safety for critical operations and missions using wearable Wireless Body Area Networks (WBANs) technology is introduced. This paradigm has a vast scope of applications, including disaster management, worker safety in harsh environments such as roadside and building workers, mobile health monitoring...

A wireless body area sensor network (WBASN) demands ultra low power and energy efficient protocols. Medium access control (MAC) layer plays a pivotal role for energy management in WBASN. Moreover, idle listening is the dominant energy waste in most of the MAC protocols. WBASN exhibits wide range of traffic variations based on different physiologica...

This paper presents a self organized asynchronous medium access control (MAC) protocol for wireless body area sensor (WBASN). The protocol is optimized in terms of latency and energy under variable traffic. A body sensor network (BSN) exhibits a wide range of traffic variations based on different physiological data emanating from the monitored pati...

Energy modeling is an important issue for designing and dimensioning low power wireless sensor networks (WSN). In order to help the developers to optimize the energy spent by WSN nodes, a pragmatic and precise hybrid energy model is proposed. This model considers different scenarios that occur during the communication and evaluates their energy con...

This article presents a novel machine learning (ML) augmented sensor fusion scheme for seamless indoor-outdoor positioning using ultra-wideband (UWB) and global navigation satellite system (GNSS) sensors. Dilution of precision (DOP) is a common metric that describes the level of geometrical uncertainty and is often applied in sensor fusion schemes....

In this survey paper, we present an extensive review of the use of RIS in 6G radio localization, highlighting their pivotal role as a low-cost, energy-efficient technology that reshapes wireless communication and localization landscapes. Investigating the versatile capabilities of RIS, we explore their dynamic control over electromagnetic wave mani...

Presents corrections to the paper, (Erratum to “UWB and GNSS Sensor Fusion Using ML-Based Positioning Uncertainty Estimation”).

The rapid advancement of autonomous and heterogeneous unmanned aerial vehicle (UAV) swarms necessitates efficient computation offloading (CO) strategies to optimize their performance in industries, e.g., disaster management, surveillance, and environmental monitoring. UAVs face constraints such as limited energy, latency requirements, and failure r...

The integration of reconfigurable intelligent surfaces (RIS) in wireless environments offers channel programmability and dynamic control over propagation channels, which is expected to play a crucial role in sixth generation (6G) networks. The majority of RIS-related research has focused on simpler, quasi-free-space conditions, where wireless chann...

This paper presents a novel Sliding Window selection scheme tailored for optimizing the Non-Overlapping Backoff Algorithm (SW-NOBA). SW-NOBA is devised to tackle inter-priority collisions, while minimizing instances of intra-priority collisions. Its adaptive nature, dynamically responding to channel conditions influenced by factors such as node den...

5G radio signal strength- and quality measurements can be used to distinguish between Line of Sight (LOS) and non- Line of Sight (NLOS) channels with good accuracy. Classification results, obtained with the use of Machine Learning (ML) methods, can be used to significantly improve positioning accuracy in complex radio environments. Two measurement...

Anomaly detection and fall prevention represent one of the key research areas within gait analysis for patients suffering from neurological disorders. Deep Learning has penetrated into healthcare applications, encompassing disease diagnosis and anomaly prediction. Connected wearable medical sensors are emerging due to computationally expensive mach...

Goal: Real-time abnormality detection in gait analysis is an open challenge. The existing state-of-the-art is limited by the fact that it does not take into account ’in-step’ anomaly detection. Timely detection of gait abnormalities during the mid-swing phase of the step (i.e., within 50ms detection time) is required to make informed gait correctio...

The Internet of Things (IoT) is an essential part of 5G, Beyond-5G (B5G), and 6G systems; it has several applications in two of the principal 5G use cases, namely ultra-reliable low-latency communications (URLLC) and massive machine-type communications (mMTC), and in their successors within B5G and 6G: extreme ultra-reliable low-latency communicati...

The deployment of 5G has exposed capacity constraints in realizing the key vision of the Internet of Everything (IoE). Therefore, the researchers are exploring potentials of Digital Twin Network (DTN) in wireless networks. DTN is a novel technology to create virtual replicas of physical environment for testing, optimizing, and managing wireless net...

This article investigates the use of Ultra-Wideband (UWB) ranging residuals for coordinate integrity estimation and their use in a filtering scheme. Typically, UWB system accuracy is improved using channel statistics to detect and mitigate non-line of sight (NLOS) effects between UWB sensors and the object to be located, potentially improving the e...

Wireless Body Area Networks (WBANs) have significantly enhanced various aspects of human life, particularly in healthcare, fitness, entertainment, sports, and etc. In WBANs, the sensor nodes are placed in and around the body along with the sink node, which collects the physiological data from these sensors and forwards it for further processing. Th...

Network slicing applied to a radio access network (RAN) offers the potential to enhance the satisfaction of service requirements and optimize resource utilization, particularly in scenarios where radio resources are limited. The dependence of RAN slice performance on the allocated bandwidth part (BWP) size has not been investigated. In this paper,...

Narrow-band Internet of Things (NB-IoT) and LTE CAT-M are part of low-power wide-area network (LPWAN) access technologies that provide long-range and energy-efficient network access to IoT devices. In this study, we conducted empirical measurements on both NB-IoT and LTE CAT-M networks inside a street manhole. Street manholes are an integral part o...

In this paper, the goal is to reduce the time needed for the placement and migration of services of Connected Automated Vehicles (CAV) using precise hybrid positioning method. First, to place a service in a Multi-access Edge Computing (MEC) node, there should be sufficient resources in the served MEC node; otherwise, the service would be placed on...

Network slicing offers the potential to enhance service satisfaction and optimize resource utilization, particularly in scenarios where radio resources are limited. Subslicing has been shown to improve the slice performance. In this paper, the monitor-analyze-plan-execute-knowledge (MAPE-K)-type management closed control loop (MCCL) is implemented...

Performing 5G coverage planning across borders introduces real-life challenges related to legalities, intercountry agreements, and binding documents. This work provides RF network modelling exercise results to provide uninterrupted 5G coverage to the Via Baltica and Rail Baltica transport corridors crossing Estonia and Latvia and on the border with...

With the advent of sixth-generation (6G) networks, significant advancements are anticipated in wireless communication, particularly in critical communication scenarios where reliable and efficient communication is of utmost importance. Device-to-Device (D2D) communication is a pivotal technology in6G which allows direct communication between nearby...

The automatic detection of gait anomalies can lead to systems that can be used for fall detection and prevention. In this paper, we present a gait anomaly detection system based on the Matrix Profile (MP) algorithm. The MP algorithm is exact, parameter free, simple and efficient, making it a perfect candidate for on the edge deployment. We propose...

Narrow-Band-Internet of Things (NB-IoT) is a promising wireless communication technology for harsh signal propagation conditions, including underground connectivity. The purpose of this study is to evaluate the real-life signal quality of an NB-IoT cellular sensor network for the monitoring and control of urban drainage systems. The implementation...

A swarm of autonomous and heterogeneous drones has many benefits in various scenarios e.g. search and rescue, disaster management, agriculture, delivery and logistics, mapping and surveying, environmental monitoring, etc. However, the presence of obstacles in the environment poses challenges to communication between drones, including network covera...

Open Radio Access Network (O-RAN) is a decentralized, intelligent, and open network architecture. RAN Network Functions (RNF) are split into Open Central Unit (O-CU), Open Distributed Unit (O-DU), and Open Radio Unit (O-RU), which are deployed on commercial hardware and cloud nodes as containerized Network Functions (CNFs). This paper presents a co...

In 5G and beyond, the network slicing is a crucial feature that ensures the fulfillment of service requirements. Nevertheless, the impact of the number of slices and slice size on the radio access network (RAN) slice performance has not yet been studied. This research is needed to understand the effects of creating subslices on slice resources to s...

Increased demand for fast edge computation and privacy concerns have shifted researchers’ focus towards a type of distributed learning known as federated learning (FL). Recently, much research has been carried out on FL; however, a major challenge is the need to tackle the high diversity in different clients. Our research shows that using highly di...

Device-to-device (D2D) enables direct communication between two-user equipment (UEs) with or without the involvement of a base station (BS). D2D communication is a vital paradigm for designing a reliable public safety network (PSN) and supports several services in the sixth generation (6G) such as target monitoring, emergency search and rescue, etc...

Device-to-device (D2D) enables direct communication between two-user equipment (UEs) with or without the involvement of a base station (BS). D2D communication is a vital paradigm for designing a reliable public safety network (PSN) and supports several services in the sixth generation (6G) such as target monitoring, emergency search and rescue, etc...

Unmanned aerial vehicle (UAV)-assisted networks ensure agile and flexible solutions based on the inherent attributes of mobility and altitude adaptation. These features render them suitable for emergency search and rescue operations. Emergency networks (ENs) differ from conventional networks. They often encounter nodes with vital information, i.e.,...

Advances in Unmanned Air Vehicle (UAV) technology have paved a way for numerous configurations and applications in communication systems. However, UAV dynamics play an important role in determining its effective use. In this article, while considering UAV dynamics, we evaluate the performance of a UAV equipped with a Mobile-Edge Computing (MEC) ser...

This paper first presents a comprehensive analysis of Non-Line-of-Sight (NLoS) error cases in the Ultra-Wideband (UWB) Active-Passive Two-Way Ranging (AP-TWR) protocol. Based on this analysis, we then propose the Adaptive Extended Kalman Filter (A-EKF) positioning method, utilizing variances calculated from AP-TWR range estimates, which are adapted...

5G systems are capable of facilitating remarkable technological advances and promoting sustainability in Internet-of-Things-centric fields, such as the Transport and Logistics (T&L) sector and applications in Connected-and-Automated Mobility (CAM). The current article provides an overview of the latest developments in the applications of the 5G mob...

5G networks promise high data rates, low latency and extreme reliability. Existing literature is saturated with simulation and numerical investigations on 5G. However, a limited number of studies are available on the evaluation of 5G networks in real-time heterogeneous environments. As 5G networks are being deployed worldwide. Therefore, it is sign...

NB-IoT technology is characterized by e.g. wide coverage, massive connectivity, reduced device energy consumption, and lower device cost, making it a suitable choice for the Internet of Things (IoT) vision. With these NB-IoT provisions, this work presents an NB-IoT based visual Smart Waste ManagementSystem (SWMS) that involve the design and develop...

This paper explores least squares (LS), median (MED), inverse distance weighting (IDW), distance weighted estimator (DWE) and three different weighted least squares (WLS) methods for Ultra-Wideband (UWB) active-passive two-way ranging (AP-TWR) measurement matrix estimation. The proposed methods were tested with practical experiments in line-of-sigh...

Device-to-device (D2D) enables direct communication between two-user equipment (UEs) with or without the involvement of a base station (BS). D2D communication is a vital paradigm to design a reliable public safety network (PSN) and support several services in the sixth generation (6G) systems such as target monitoring, emergency search and rescue,...

Gait analysis is widely used for human disability level assessment, physiotherapeutic and medical treatment efficiency analysis. Wearable motion sensors are most widely used gait observation devices today. Automated detection of gait abnormalities, namely incorrect step patterns, would simplify the long term gait assessment and enable usage of corr...

This paper proposes two general active-passive two-way ranging (TWR) methods: AP1-TWR and AP2-TWR. The proposed methods rely on 2 types of anchors: active-passive and passive-only. The first type actively takes part in packet exchange and listens to transmissions of other active-passive anchors, and the second type only listens. Pairing these conce...

Recently, drones technology started unleashing numerous novel applications and services and became one of the killer applications for the Mobile Edge Computing (MEC) paradigm. The main challenge for real-time applications is, however, transferring data between data processing servers and drones, which yields considerable latency and energy consumpt...

The fifth-generation (5G) and beyond 5G (B5G) wireless networks introduced massive machine-type communications (mMTC) to cope with the growing demand of massive Internet of Things (IoT) applications. However, the heterogeneous characteristics of massive IoT and diverse quality of service (QoS) requirements may lead to severe interference that could...

Device-to-device communication, as provided by the third generation partnership project standardization, can play a vital role in designing a reliable pervasive public safety network, which allows the user equipment (UEs) to communicate directly with each other in emergency situations. In this paper, we analyze the performance of direct discovery,...

Machine Learning (ML) techniques can play a pivotal role in energy efficient IoT networks by reducing the unnecessary data from transmission. With such an aim, this work combines a low-power, yet computationally capable processing unit, with an NB-IoT radio into a smart gateway that can run ML algorithms to smart transmit visual data over the NB-Io...

Today, unmanned aerial vehicles (UAVs) or drones are increasingly used to enable and support multi-access edge computing (MEC). However, transferring data between nodes in such dynamic networks implies considerable latency and energy consumption, which are significant issues for practical real-time applications. In this paper, we consider an autono...

In Public Safety Networks (PSNs), the conservation of on-scene device energy is critical to ensure long term connectivity to first responders. Due to the limited transmit power, this connectivity can be ensured by enabling continuous cooperation among on-scene devices through multipath routing. In this paper, we present a Reinforcement Learning (RL...

Device-to-device communication, as provided by the third generation partnership project standardization, can play a vital role in designing a reliable pervasive public safety network, which allows the user equipments to communicate directly with each other in emergency situations. In this paper, we present experimental results and evaluate the perf...

NarrowBand Internet of Things (NB-IoT) is an emerging cellular IoT technology that offers attractive features for deploying low-power wide area networks suitable for implementing massive machine type communications. NB-IoT features include e.g. extended coverage and deep penetration for massive connectivity, longer battery-life, appropriate through...

In this paper, we propose an inter-cell interference (ICI) minimization scheme for uplink transmission in the narrow-band internet of things (NB-IoT) systems. We first establish the theoretical ICI problem formulation and propose its corresponding solution for the orthogonal multiple access (OMA) NB-IoT system. Based on the theoretical formulation,...

NarrowBand Internet of Things (NB-IoT) is an emerging cellular IoT technology that offers attractive features for deploying low-power wide area networks suitable for implementing massive machine type communications. NB-IoT features include e.g. extended coverage and deep penetration for massive connectivity, longer battery-life, appropriate through...

The use of Aerial Base Stations (ABSs) has received a great deal of attention in academia and industry as a means to support the cellular communication traffic growth. In this article, we focus on obtaining the optimal altitude of an ABS using two criteria-maximum cell coverage area and minimum Symbol Error Rate (SER). Our study is done by using a...

Smart body area networks (SmartBAN) is an emerging wireless body area networks (WBAN) standard proposed by the European Telecommunications Standards Institute (ETSI). This paper first examines the potential of SmartBAN medium access control (MAC) layer with scheduled access to support a myriad of WBAN applications, having diverse data rate requirem...

This paper proposes a generalized approach combining two-way ranging (TWR) and passive ranging methods, called active-passive two-way ranging (AP-TWR). The proposed approach offers a generalized solution for a wide range of anchor configurations in positioning systems. The possibility to define active-passive and passive-only anchor roles allows sc...

See the pre-print version here: https://www.researchgate.net/publication/345942851_Active-Passive_Two-Way_Ranging_Using_UWB

Link/channel scheduling is a process by which different channels within the allowed set of frequencies or different timeslots from a single channel are assigned to achieve minimum interference to the neighbouring nodes and higher efficiency. Existing channel scheduling approaches are often evaluated under the assumption of random mobility model. Th...

In an event of a disaster, the connectivity of on-scene available User Equipment (UE) to the first responders is important because of the unavailability of conventional networks. Therefore, in this paper, considering the deployment of both the Unmanned Aerial Vehicle (UAV) and Mobile Command Center (MCC), we investigate end to end connectivity of U...

The growing network density and unprecedented increase in network traffic, caused by the massively expanding number of connected devices and online services, require intelligent network operations. Machine Learning (ML) has been applied in this regard in different types of networks and networking technologies to meet the requirements of future comm...

In scenarios, like critical public safety communication networks, On-Scene Available (OSA) user equipment (UE) may be only partially connected with the network infrastructure, e.g., due to physical damages or on-purpose deactivation by the authorities. In this work, we consider multi-hop Device-to-Device (D2D) communication in a hybrid infrastructu...