Single-Site Localization Based on a New Type of Fingerprint for Massive MIMO-OFDM Systems

Localization for mobile devices is drawing increasing interest from both industry and academia as location-based services spring up in recent years. For rich scattering environments, such as urban areas and indoor corridors, fingerprint-based localization techniques are very promising. In this paper, we propose a fingerprint-based single-site localization method for massive multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) systems. A new angle delay channel power matrix fingerprint is extracted from instantaneous channel state information by taking full advantage of the high resolution in the angle and delay domains for massive MIMO-OFDM systems. A new fingerprint similarity criterion is proposed to facilitate localization. Based on the new criterion, an efficient location estimation method is developed. To reduce storage overhead and matching complexity, we also propose a fingerprint compression method and a two-stage fingerprint clustering algorithm for database preprocessing. Numerical results demonstrate the desirable performance of the proposed localization method.