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Title: Custom Over-the-air Scalable mmWave Testbed for Fast TTD-Based Rainbow Beam Training
Millimeter-wave (mmWave) systems require a large number of antennas, which makes the beam training challenging and time-consuming for conventional phased arrays. Recently, a true-time-delay (TTD) array-based beam training algorithm has been shown as an effective solution to overcome the training overhead in large arrays. In this paper, we present a custombuilt over-the-air (OTA) testbed to study the effects of hardware impairments on the TTD-based beam training and verify its feasibility in a real system. We proposed an orthogonal matching pursuit (OMP) based reconstruction algorithm along with a phase calibration dictionary to combat nonidealities such as strong frequency selectivity and phase misalignment in the received raw IQ signal. Post-processing results showed that with the nonideality effects properly handled, the 3D TTD beam training algorithm can achieve high AOA estimation accuracy.  more » « less
Award ID(s):
1955306
PAR ID:
10538243
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
IEEE
Date Published:
ISBN:
978-1-7281-9054-9
Page Range / eLocation ID:
1903 to 1908
Format(s):
Medium: X
Location:
Denver, CO, USA
Sponsoring Org:
National Science Foundation
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