On the Mapping between Steering Direction and Frequency of a Uniform Linear Array with Fixed True Time Delays
Conference: WSA 2020 - 24th International ITG Workshop on Smart Antennas
02/18/2020 - 02/20/2020 at Hamburg, Germany
Proceedings: ITG-Fb. 291: WSA 2020
Pages: 6Language: englishTyp: PDFPersonal VDE Members are entitled to a 10% discount on this title
Rave, Wolfgang; Jans, Christoph (Vodafone Chair Mobile Communications Systems, Technische Universität Dresden Germany)
Frequency dependent beam steering occurs when a wideband signal is transmitted or received by a uniform linear array and fixed true time delays τ of the order of the reciprocal bandwidth 1/fb are applied between adjacent antenna signals. The phenomenon is explained by the fact, that phase shifts depending on the product ftau between frequency and delay occur in the array propagation vector. In this work the mapping φ = g(f) between steering angle phiAOD and frequency that depends on carrier frequency fc via the antenna element spacing and relative bandwidth κ = fb/fc is derived in closed form. The effect becomes implementable when the absolute bandwidth is of the order of 1 GHz or higher so that the required delays are multiples of the order of 1 ns, i. e. in mm wave and RADAR applications. It may be used for beam selection by estimating the receive power spectral density.