Channel (broadcasting)

MIMO

Extremely high frequency

Beamforming

Base station

Computer science

Angle of arrival

Antenna (radio)

Transmitter

Telecommunications link

Engineering

Transmission (telecommunications)

Telecommunications

Algorithm

Multipath propagation

Codebook

Precoding

Electronic engineering

User equipment

Channel sounding

IEEE Transactions on Wireless Communications

Communication at millimeter wave (mm-wave) bands is expected to become a key ingredient of the next generation (5G) wireless networks. Effective mm-wave communications require fast and reliable methods for beamforming at both the user equipment (UE) and the base station sides, in order to achieve a sufficiently large signal-to-noise ratio after beamforming. We refer to the problem of finding a pair of strongly coupled narrow beams at the transmitter and receiver as the beam alignment problem. In this paper, we propose an efficient BA scheme for single-carrier mm-wave communications. In the proposed scheme, the BS periodically probes the channel in the downlink via a pre-specified pseudo-random beamforming codebook and pseudo-random spreading codes, letting each UE estimate the angle-of-arrival/angle-of-departure (AoA-AoD) pair of the multipath channel for which the energy transfer is maximum. We leverage the sparse nature of mm-wave channels in the AoA-AoD domain to formulate the BA problem as the estimation ...

Efficient Beam Alignment for Millimeter Wave Single-Carrier Systems With Hybrid MIMO Transceivers