Integrated Sensing and Communicationusing OFDM and Stepped FMCWSignals : Proof-of-Concept and Evaluation with Software DefinedRadios

Abstract: The thesis work shows the implementation of sensing and communication, so a basic knowledge of analog and digital communication systems is needed to understand this paper Background. With the increase in smart devices, the bandwidth requirements are increased, which created congestion in the radio spectrum resources. To overcome this spectrum congestion, Integrated Sensing and Communication (ISAC) can be used. This can be achieved by using Orthogonal Frequency-Division Multiplexing (OFDM) signals. In ISAC, both sensing and communication use the same resources,which in turn predominantly improves the efficiency of the spectrum resources usage and reduces the cost of hardware. Objectives. The main aim of this research is to integrate radar sensing and communication using Software Defined Radios (SDR) and GNU Radio. The goal is to design a signal waveform and a receiver algorithm supporting both sensing and communications and then carry out experiments on an SDR unit to evaluate the functionality and performance. Methods. Experimentation is used in this research and is conducted at Ericsson Research Laboratory. The experiment is divided into three major parts. First, to test the sensing functionalities using Frequency Modulated Continuous Waves (FMCW). Second, to test the communication functionalities using OFDM signals. Third, to design the receiver algorithm and signal waveform for ISAC. To verify the dual functional paradigm, the results from the ISAC are compared with the individual test results of sensing and communications using FMCW and OFDM signals. Results. A receiver algorithm is designed to calculate the sensing range and BER of ISAC using an SDR. The results show the possibility of implementing ISAC using OFDM in GNU Radio with SDR. The thesis project can also be viewed as a proof of concept for ISAC on SDR, helping in providing useful information related to radar sensing and communication using OFDM and performance evaluation. Conclusions. The experimental results show the dual-functional waveform for ISAC, helping in the evolution of 5G and beyond 5G communication systems. The identified drawbacks can be used by future researchers working on advanced 5G mobile communication systems to develop more efficient systems. Keywords: Communications, FMCW, GNU Radio, ISAC, OFDM, SDR, Sensing.