scholarly journals Impact of Probe Configurations on Maximum of Test Volume Size in 3D MIMO OTA Testing

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Weimin Wang ◽  
Huaqiang Gao ◽  
Yongle Wu ◽  
Yuanan Liu

With the development of multiple-input-multiple-output (MIMO) technology, the over-the-air (OTA) testing of MIMO capable devices with different sizes needs to be conducted for performance evaluation. The device under test (DUT) should be within a tridimensional test volume created by multiprobe configurations. Thus, determining the maximum size of test volume could be vital to test the DUT of different size and larger test volumes should be adopted to evaluate larger DUTs. All types of probe configurations including the fixed and the flexible probe configurations are investigated in this paper to address this issue. The maximum of test volume size (MTVS) is determined within the given error threshold of spatial correlation for a given probe configuration. Simultaneously, the impact of different probe configurations on MTVS is studied in order to obtain larger MTVSs. Simulation results show that larger MTVSs can be obtained by utilizing the optimal probe configuration with any given 3D channel model for 3D MIMO OTA testing.

2017 ◽  
Vol 2017 ◽  
pp. 1-15 ◽  
Author(s):  
Yoshio Karasawa ◽  
Katsuhiro Nakada ◽  
Guijiang Sun ◽  
Rikako Kotani

We present four new developments for a multiple-input multiple-output (MIMO) over-the-air measurement system based on our previous studies. The first two developments relate to the channel model for multipath environment generation. One is a further simplification of the circuit configuration without performance degradation by reducing the number of delay generation units, which dominate the performance limit when implementing the circuit on a field-programmable gate array (FPGA). The other is to realize spatial correlation characteristics among the input ports on the transmission side, whereas the previously proposed channel model did not consider this correlation. The third development involves the details of implementing the MIMO fading emulator on an FPGA as a two-stage scheme. The fourth is the demonstration of application examples of the developed system.


Author(s):  
A. Monti Guarnieri ◽  
D. Giudici ◽  
P. Guccione ◽  
M. Manzoni ◽  
F. Rocca

Abstract. Multiple-Input-Multiple Output (MIMO) Synthetic Aperture Radar (SAR) along-track formations can be used to fraction the power resources into compact, lightweight and cost-effective satellites, or to extend the swath coverage beyond the limit provided by a small antenna. In this second case, the Pulse Repetition Frequency (PRF) is kept low by implementing an inversion that solves up to N−1 ambiguities, given N observations. The simultaneous illumination – that allows for the N² gain due to the coherent combination of the N transmitters and the N receivers, is analyzed and shown not to be critical, as the more than N=2 sensors are assumed. Performance is evaluated for the N=2 and N=3 cases and compared with the Single Input Multiple Output formations, where one sensor is transmitting, and all are receiving. Finally, the impact of the across-track deviation from the orbit is modeled and evaluated.


2020 ◽  
Vol 71 (3) ◽  
pp. 222-226
Author(s):  
Zouhair Al-qudah

AbstractThe Gaussian multiple-input multiple-output (MIMO) orthogonal relay channel (ORC) is investigated. The transmission from source to relay is done over a channel that is orthogonal to source-destination and relay-destination channels. Practically, this assumption is made such that many communication devices from different technologies are exploited in relaying the source’s signal into its destination. For this channel model, the capacity is initially derived. Thereafter, we propose a transmission algorithm to achieve the derived capacity. Further, to support our theoretical results, many numerical examples are presented.


2014 ◽  
Vol 716-717 ◽  
pp. 1194-1198
Author(s):  
Xiao Yu Li ◽  
Xiao Fei Zhang ◽  
Da Zhuan Xu ◽  
Qui Ming Zhu

This paper addresses the problem of the effect of different antenna layouts on the capacity of massive multiple-input multiple-output (MIMO) system capacity. Based on the narrow-band, flat fading channel model, the effect of scattering environment and antenna layout are considered by incorporating the power azimuth spectrum (PAS) and the array manifold vector. Under the same antenna aperture, six antenna layouts are investigated among which the UCA yields the best capacity while ULA yields the lowest capacity. The more symmetric the antenna geometry is, the better capacity performance it has.


Electronics ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 8
Author(s):  
Wei Lu ◽  
Yuxi Li ◽  
Yicai Ji ◽  
Chuanjun Tang ◽  
Bin Zhou ◽  
...  

The Chang’e-5 lunar exploration mission of China is equipped with a Lunar Regolith Penetrating Radar (LRPR) for measuring the thickness and structures of the lunar regolith in the landing area. Since the LRPR is stationary, an ultra-wideband multiple-input multiple-output (MIMO) array is designed as a replacement for conventional mobile subsurface probing systems. The MIMO array, with 12 antenna elements and a switch matrix, operates in the frequency band from 1.0 to 4.75 GHz. In this work, the design and layout of the antenna elements were optimized with respect to the lander. To this end, the antenna elements were designed as miniaturized Vivaldi antennas with quarter elliptical slots (i.e., quarter elliptical slotted antenna, or QESA). QESAs are significantly small while being able to mitigate the impact of the lander on antenna electrical performances. QESAs also have a wide operating bandwidth, flat gain, and excellent time domain characteristics. In addition, a high-temperature resistant ultra-light radome with high transmissivity is designed to protect the external antenna array. After calibration, the MIMO array is used to detect targets embedded in volcanic ash. The detection depth reaches 2.5 m, and the detection effect is good.


2021 ◽  
Author(s):  
Joydev Ghosh ◽  
Huiling Zhu ◽  
Huseyin Haci

<div>A novel channel model has been proposed for mobile millimeter-wave (mmWave) massive multiple-input multiple-output (MIMO) communications to evaluate the effect of end-user mobility. In this model the variance of number of clusters and number of rays generated from each cluster is taken into account that is novel and different from widely used channel models. Two optimum codebook based beam-tracking schemes multi-objective joint optimization codebook (MJOC) and linear hybrid combiner (LHC) have been proposed for the novel channel model and their performance for spectral efficiency (SE) is presented. Performance for the two most commonly used channel state information (CSI) estimation approaches is investigated. Finally, the relationship between the beamforming training blocks and optimal beam tracking scheme is presented.</div>


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