Service Antenna Array-Based Parameter Estimation for Decimeter Level Indoor Localization

Since the antenna interval of service antenna array for communication is greater than half a wavelength and does not satisfy the spatial sampling theorem, it is a great challenge to leverage service antenna array for channel state information-based signal parameters estimation, such as time-of-flight (TOF) and angle-of-arrival (AOA) estimation. To overcome this challenge, this letter proposes a diagonal spatial mapping-based multiple signal classification (MUSIC) and matching pursuit (MP) fusion (DSM-MMF) algorithm. First, a new virtual linear array is constructed by mapping the service antenna array on the diagonal of the plane array. Second, a fusion AOA and TOF estimation for the signal mapped on the virtual linear array is realized by utilizing the MUSIC and MP fusion algorithm. Third, through the unique geometric relationship between the virtual linear array and the service antenna array, the AOA and TOF can be obtained. Finally, experimental results show that the DSM-MMF’s median localization error is about four decimeters.

I. Introduction

Integrated sensing and communication (ISAC) has attracted intensive attention, and it has been regarded as an important research direction in sixth generation (6G). In our traditional applications, in order to achieve diversity and reduce interference in communication, the antenna spacing of communication equipment is often set larger. In the field of sensing, in order to obtain accurate target parameters, the spacing between equipment antennas must be less than half a wavelength. it is a challenge for us to use the existing communication equipment for target sensing and achieve ISAC.