Supervised MASTER Theses


Theses Summary Abstracts 


Future wireless systems are expected to serve very challenging requirements such as enhancing the spectral efficiency and transmission reliability, securing the transmission and guaranteeing low-complexity and low latency communications. In this scope, we investigate and propose in this work some promising research directions for ensuring an effective design for future wireless systems: 1) we study the combination of multi-dimensional OFDM modulations and non-coherent detection for enhancing the spectral efficiency and reducing the complexity in the design of future wireless systems. Particularly, in this regard, we propose and study a new technique termed as 'Non-Coherent Orthogonal Frequency Division Multiplexing with Subcarrier Power Modulation (NC-OFDM-SPM)' for doubling the spectral efficiency per receiving user/device through the exploration of the power of the subcarriers inside an OFDM block as an additional dimension for conveying extra information. The use of non-coherent detection ensures low-design complexity in this idea. 2) We propose a novel physical layer security design for effective and secure future multiple access communications. The proposed design is called 'Multi-User Auxiliary Signal Superposition Transmission (MU-AS-ST)' which is presented as an alternative design for the current conventional Power Domain NOMA which was studied by the 3GGP (3rd Generation Partnership Project) from release 13 till 16 under the name 'Multi- User Superposition Transmission (MUST)' before being eliminated from the study items in release 17. The proposed design superimposes auxiliary signals with the users data for can- celling the inter-user interference fully while achieving perfect secrecy against both internal (presence of an untrusted legitimate user) and external eavesdroppers. MU-AS-ST achieves better reliability than conventional NOMA and does not use Successive Interference Cancellation. Moreover, this design works for the combination of any two users regardless of their distance from the base station unlike conventional NOMA which works only for the cases where there exists a significant path-loss channel difference between paired (or super-imposed) users. Furthermore, carrying all the processing at the base station makes this design an appealing choice for processing-restricted communication devices such as IoT devices. 3) We study the integration of multi-dimensional OFDM modulation formats in multiple access setups for enhancing the spectral efficiency per area and per device for a more optimal usage of the spectrum allocated for wireless communications. As an example of this integration, we study the combination of OFDM-SPM with MU-AS-ST where we show that this leads to doubling the spectral efficiency per area and per device. The proposed designs were studied thoroughly and their performance was evaluated in terms of different performance metrics such as bit error rate, spectral efficiency, design complexity and peak to average power ratio (PAPR). Keywords: auxiliary signals, eavesdropping, IoT, low-complexity, multi-dimensional OFDM, multiple access, non-coherent detection, physical layer security, power domain NOMA, reliability, spectral efficiency, subcarrier power modulation, wireless communications. 


Muhammad Furqan Zia, "Novel Advanced Non-Orthogonal Multiple Access Security Scheme for 6G and Beyond Communication Networks", 22-01-2021 

The future wireless communication systems demand enhanced security and reliability than the current systems. In this research, we propose a more simple yet efficient physical layer security (PLS) technique for achieving reliable and secure communication in the multiple-input single-output non-orthogonal multiple access (MISO-NOMA) system. This system is capable of providing enhanced confidential communication as well as inter-user interference cancellation without using the successive interference cancellation (SIC) method. As conventional NOMA was already adopted under the name of multi-user superposition transmission (MUST) in release 13 of 3GPP but recently excluded from 3GPP-release 17 due to its performance degradation. In this work, we have analyzed these drawbacks and presented a new kind of NOMA with better performance results in cases where conventional NOMA fails. The proposed algorithm combines the benefit of pre-coder matrices with simultaneous transmission using antenna diversity to enhance the security and reliability of wireless communications with no leakage of information. The proposed new NOMA is specially designed for IoT devices that require limited processing at the receiver. The effectiveness of the developed scheme is verified and proven by extensive numerical simulations. 


Joel Poncha Lemayian, "UAV-based Smart Rescue System Utilizing a Novel Wireless Communication Technique With Enhanced Security Against Internal And External Attacks", 22-01-2021 

Numerous problems have been experienced due to the current exponential rise the urban population. Such challenges include insecurity and disaster management. These problems and more will be exacerbated in the future due to the persistent population increase in urban developments. It is therefore critical that new and efficient ways of managing such challenges are realized. Drone technology has been used in many applications due to its flexibility and cost-effectiveness. Such applications include goods delivery, surveillance, and tracking. Nevertheless, security has been a major concern and a stumbling block to further applications of drones. This work proposes an autonomous first response drone-based (Auto-FRD) smart rescue system with a novel secure communication technique. The Auto-FRD paradigm uses drones to provide quick responses to critical situations in a smart city setting. Additionally, the novel secure communication technique between the drone and the command centers is designed to utilize the characteristics of the channel such as noise and interference to enhance security by adding auxiliary signals to the transmitted data. Moreover, the Auto-FRD system is implemented using cheap LoRa technology. The efficiency and novelty of the proposed paradigm are presented via mathematical analysis and validated by Monte Carlo simulations. Results indicate that the proposed system drastically reduces the response time compared to conventional methods. Also, optimal base station placement is calculated using metaheuristic algorithms. 

SADIQ IQBAL, "New transmission methods for improving the performance of future 6G and beyond networks by utilizing signal superposition and precoding techniques", 2022 

To provide superior spectral efficiency, enhanced system reliability, improved SNR gain, and be able to completely utilize a network's resources without sharing and interference among users, we propose four communication designs; 1) The first design includes a signal superposition-based dual transmission communication technique that is capable of simultaneously improving data rates from one side and reducing data errors from another side. 2) The second design includes a single-input multiple-output design for better deployment of power resources than currently employed systems. 3) The third design includes a new communication scheme that can simultaneously provide multiplexing gain and diversity gain. 4) The fourth design talks about PU-MIMO-ST (Precoded Universal MIMO Superposition Transmission) technique that can provide a network's complete resources and capabilities to every user without any interference and sharing at all. These proposed communication designs perform better than the conventional systems and provide more benefits for future networks. 


SHAHEER KHALID, "Novel comp designs for improving the performance of cell- edge users in future wireless networks", 2022 

The increase in cellular traffic is leading the advancement of cellular technologies to massively improve the quality of high-end communication experiences such as high throughput, high reliability, and universal access. To accomplish these demands in a cellular environment is a huge challenge, and it is more critical at the cell edges infected with interference. To address these requirements and challenges, we propose novel Enhanced Cooperative Multi-Point (eCoMP) and Hybrid Coordinated Multi-Point (H-CoMP) designs for cell-edge users to combat inter-cell interference (ICI), inter-user interference (IUI), and improve spectral efficiency. Superimposed supporting signals and channel-based precoders are designed to deal with ICI, remove channel effects, and provide reliable communication to cell-edge users. Mathematical models and simulations highlight the inventiveness and efficiency of the proposed paradigms compared to other competitive schemes. The results show the performance of the proposed solutions and the ability to reduce system complexity, leading to enhanced overall system performance. 


HAMZA ALI, "Protecting IMSI from fake base stations exploitation and spoofers' impersonations in 5G and beyond cellular networks", 2022 

Fifth age (5G) portable organizations require confirmed and completely got transmissions between client gadgets and 5G base stations (gNodeB). In the ongoing 5G innovation standard, cell phones can't recognize a genuine and a phony base station (BS) by observing the guideline 5G security conventions. This weakness is a perilous security issue recognized in 5G cell networks around the world, where programmers and spoofers can undoubtedly imitate or hack the important data of portable clients. Albeit 5G security conventions are upgraded to forestall such sorts of assaults, counterfeit BSs compromise the security of remote correspondence organizations. To the best of the creators' information, there is right now no security technique accessible in the writing that can empower clients to distinguish who is sending the association demand reaction., in this work, we propose a clever hack-verification structure that can totally get IMSI bringing about avoidance against satirizing assaults. 


MUHAMMET KIRIK, "Multiple input multiple output with antenna number modulation and its applications", 2022  

Multi-user applications of multiple input multiple output systems with antenna number modulation (MIMO-ANM) are proposed in this thesis to be used instead of conventional MIMO and its other variations for providing more advantageous and reliable data transmission in future wireless systems. In the MIMO-ANM scheme, the additional data bits are conveyed by changing the number of active transmit antennas instead of their indices. To utilize all available antennas of MIMO-ANM, Multi-User MIMO-ANM and Multi-User OFDM-SNM are proposed in this thesis as novel multi-access data transmission methods that target serving multiple users by dedicating the antennas/subcarriers used for implementing ANM/SNM to serve a far user, whereas the remaining antennas/subcarriers are used to send data for a near user. The acquired results show that MIMO-ANM and its applications for different communication scenarios offer highly competitive performances and desirable benefits for future wireless networks. 



MOHAMMED KHER NOMAN IBRAHIM HIJAZI, "Signal Space Diversity and Convolutional Neural Network Based Equalizer for Improving the Reliability Performance of OFDM with Sub-carrier Power Modulation", 10-06-2021 

As the demand for higher data rates increases exponentially, there is a shift towards exploring contemporary techniques that are likely to offer higher spectral efficiency. A new modulation technique termed as orthogonal frequency division multiplexing with sub-carrier power modulation (OFDM-SPM) has recently been introduced. It is an original technique that is still largely underexplored and aims at transmitting more bits per sub-carrier ., it was found that the additional data stream conveyed by subcarriers' power has a higher bit error rate (BER) performance compared to the data stream conveyed by conventional modulation schemes. To overcome this shortfall, signal space diversity (SSD) is proposed in this work to be integrated with OFDM-SPM to help improve the overall BER performance. Furthermore, the performance results of OFDM-SPM-SSD are compared with those of OFDM-SPM with maximal ratio combining (MRC), and the obtained results show that OFDM-SPM-SSD offers superior performance. To improve the reliability performance of OFDM-SPM furthermore, more I will propose the use of a CNN-based equalizer for OFDM-SPM. 


ABDELRAHMAN M.A ABUQAMAR, "STBC and Back Propagation Artificial Neural Network for Improving the Performance of Orthogonal Frequency Division Multiplexing with Subcarrier Power Modulation",  10-06-2021 

Orthogonal Frequency Division Multiplexing with Subcarrier-Power Modulation (OFDM-SPM) has recently been proposed as a promising, the OFDM-SPM technique is compounded with Alamouti space-time block coding (STBC) in a multiple-input-single-output (MISO) set up to study, investigate, and quantify the wireless system's performance of their combination over a multi-path Rayleigh fading channel. For making STBC work well with OFDM-SPM, a suitable equalizer is proposed for detecting the SPM power bits, and it is observed that there is a considerable improvement in the BER. It was found that the sub-carrier optimized power-reassignment scheme provides the best BER performance for the proposed transmission scheme.