Linearization and Efficient 5G Radio Front-Ends

Evolution of the Transmit Radio Front-End from 2G to 4G for mobile devices and infrastructure, with cost and energy efficiency driving demand, has resulted in the widespread adoption of envelope tracking and Doherty techniques for efficiency enhancement, augmented by digital predistortion. The step-change in 5G requirements, especially bandwidth, operating frequency and beamforming, presents an opportunity…

High-Resolution Directional Channel Measurements at 67 GHz and Advanced Analysis of Interactions Using Geometric Information

This paper presents results from a high-resolution channel measurement campaign at 67GHz in a street canyon in Tokyo, with focus on an extended evaluation method which incorporates map-based side information. Besides being beneficial for validating the results of the path estimation, the analysis allows the identification of main sources of interaction and the differentiation between…

5G Antenna Characterization in the Far-Field

5G mobile devices and base stations will be operating antenna arrays and beam-steering techniques in the millimeter-wave region. The question of the far-field measurement distance is particularly critical for such technologies as a larger over-the-air test range means dynamic range issues and significantly larger cost. The traditionally used formula for the far-field distance aims at…

Characterization of mm-Wave Channel Sounders up to W-Band and Validation of Measurement Results

In this paper, the characterization of mm-wave channel sounders and validation of measurement data are discussed. Suitable procedures and metrics like the dynamic range and the maximum measurable path loss are proposed for this purpose. They are illustrated by using measurement data at 28 and 82GHz from back-to-back measurements in the laboratory as well as…

Estimation of DoA Based on Large-scale Virtual Array Data

Future 5G communication systems operating in the mmwave bands (6-100 GHz) will rely on multi-antenna techniques like beamforming and MIMO 1. Therefore, measurement and description of spatial channel information (direction of arrival DoA, direction of departure DoD) is of high relevance for mm-wave system design and channel modeling.