Open AccessAnalogue beamforming solution for beam‐alignment problem
Author(s) -
Rastegari Mahdi,
Olfat Ali,
Amini Ebrahim
Publication year - 2020
Publication title -
iet communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.355
H-Index - 62
eISSN - 1751-8636
pISSN - 1751-8628
DOI - 10.1049/iet-com.2020.0150
Subject(s) - beamforming , codebook , computer science , transmitter , antenna (radio) , antenna array , beam (structure) , quadratic equation , array gain , power (physics) , algorithm , electronic engineering , telecommunications , mathematics , engineering , optics , physics , channel (broadcasting) , geometry , quantum mechanics
Analogue only beamforming generally refers to a structure of analogue phase shifters that have no control over the amplitude of the signals and are utilised in millimetre‐wave massive multi‐input multi‐output systems to reduce the cost and power consumption. Conventional analogue only beamforming methods are based on beam‐training and subspace sampling where the transmitter and receiver select the best beamformer and combiner from a list of predefined beam patterns to maximise the beamforming gain. In this study, first, the beam‐alignment problem is formulated as a quadratic optimisation problem with quadratic constraints. Then, a practical solution for analogue only beamforming is proposed to maximise beamforming gain. The proposed method has no assumption on the array structure or isotropic antenna elements in the array. Also, a new method is proposed to design sub‐codebooks to reduce the construction time of the codebook. Simulation results also corroborate the analytical results and performance of the proposed method.