Optimal Waveform Design for Integrated Localization and Communication in OFDM Systems

With the growing demand of the fusion of communication and localization functionalities, the integrated localization and communication (ILAC) techniques have drawn significant research interests. In this paper, we focus on the waveform design in orthogonal frequency division multiplexing (OFDM) systems to improve the performance of both communication and localization. A dual-functional system where the base station transmits downlink signals to communicate with multiple users as well as provide localization service simultaneously is established. The performance metrics of communication and localization are theoretically analyzed. The waveform is firstly optimized to minimize the error bounds of position estimation. Then the multiuser interference is minimized to guarantee communication performance through a further waveform optimization algorithm. Finally, the performance trade-off of ILAC is investigated in consideration of different weights of these two functionalities, and the corresponding waveform design method is proposed. Through numerical results, we show that the proposed waveform optimization methods are able to improve the performance of ILAC in OFDM systems, and is feasible to cover heterogeneous ILAC scenarios.