Direction-of-Arrival Estimation Using Single Antenna in High-Speed-Train Environments

In this paper, a measurement campaign in high-speed- train (HST) environments is introduced where the down-link signals of an in-service Universal Mobile Terrestrial System (UMTS) deployed along a HST railway between Beijing and Shanghai were required by a single receiving antenna. Channel Impulse Responses (CIRs) are extracted from the data received in Common PIlot CHannels (CPICHs). The train speed is estimated by exploiting the characteristics of the Doppler frequency trajectory of the Line-of-Sight (LoS) path. Direction-of-Arrivals (DoAs) are estimated based on the Space-Alternating Generalized Expectation-maximization (SAGE) principle by constructing a virtual antenna array constructed on the knowledge of the train speed.