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This paper introduces a real-time multiple input and multiple output (MIMO) channel sounder to measure the vehicle-to-vehicle (V2V) propagation channel at 5.9 GHz. Compared to the existing V2V channel sounders, our design emphasizes on improving the stability of the setup and increasing the MIMO snapshot rate. The system stability allows us to develop a high resolution parameter extraction algorithm...
With MIMO, Wi-Fi led the way to the adoption of antenna array signal processing techniques for fine-grained localization using commodity hardware. These techniques, previously exclusive to specific domains of applications, will spur interest to reach beyond localization, and now allow to consider estimating the device's orientation in space, that once required other sources of information. Wi-Fi's...
An improved version of effective diversity gain (EDG) evaluation system is proposed for multiple-input multiple output (MIMO) and diversity antennas. By enhancing the sensitivity of the RF power detection module and increasing rejection of background noises, measurements can now be conducted in actual propagation environments. The control computer is replaced with a laptop to improve system mobility...
The multi-probe anechoic chamber measurement methodology (MPAC) for quantifying the MIMO OTA performances of multiple antennas wireless terminals is described in [1-2-3-4] and is designed for emulating the spatial characteristics of the propagation models defined in [5]. This testing methodology has been currently the only approved by CTIA for measuring radiated performances of MIMO (TM3) wireless...
In this paper, a low complexity microwave based direction finding (DF) system is presented. The proposed system consists of single six-port (SP) circuit integrated with a reconfigurable multiple-input-multiple-output (MIMO) antenna system. The proposed design is a complete integrated solution with DF capabilities for cognitive radio platforms. The design is suitable to be used in compact wireless...
Massive MIMO has been shown to greatly improve spectral and transmit-energy efficiency. When implementing a massive MIMO system, one challenge is high hardware complexity. A solution is to reduce the number of radio frequency (RF) transceiver chains by performing antenna selection. However, a full RF switch that connects the antennas and RF chains can be highly complex and incurs significant loss...
Relative calibration has been proposed as a simple way to practically exploit the reciprocity of the wireless channel. It is based on a simple convolutional model for the relationship between the channel impulse responses in both directions, and accounts for the discrepancies between transmit and receive radio-frequency components, without the need for specific calibration hardware. However, the relative...
In this paper, we present a wideband distributed bidirectional multiple-input — multiple-output (MIMO) channel sounder. It is developed for characterizing up to 4×4 MIMO channel in four frequency bands from 2GHz to 15GHz with 100MHz bandwidth. To fully understand the dynamic characteristics of multilink MIMO, such as distributed and cooperative MIMO, the radio over fiber (RoF) techniques is adopted...
In Ilmenau, Germany, a new laboratory is under construction for testing mobile communication equipment, both satellite and terrestrial. This contribution focuses on Over-The-Air testing of terrestrial mobile terminals and on applications of Wave Field Synthesis in this laboratory. The terrestrial research in the lab will mainly serve scientific purposes, as research into OTA test methodologies, also...
Following the growing interest in Over The Air testing of Multiple Input Multiple Output handset antenna systems, this paper presents a non-galvanic measurement tool for early antenna performance estimation in the prototyping and testing stages of the development process. The necessity for removing the coaxial cables, is here demonstrated with an example MIMO parameter - correlation. It is found by...
A universal compact hardware platform for broadband MIMO channel measurement which includes the baseband and RF transceivers is developed in this paper. The developed platform can support bidirectional channel measurement with up to 6×6 MIMO configuration flexibly by the TDD manner. Cyclically shifted symbols designed based on the Chu sequences are sent from the transmitter simultaneously, while at...
In this paper, we proposed a novel approach to the design of MIMO transceiver for channel measurement on the system level. Transmit symbols based on the Chu sequences are adopted in the transmitter. Based on the design, a hardware platform for MIMO channel measurement in indoor environments has been developed to complete the real-time channel measurement for further channel estimation. Using the hardware...
This paper presents analysis results of the wideband MIMO channel based on indoor measurements. An accurate characterization of the K-factor is very important in design issues, especially for MIMO and broadband networks. We have performed measurement campaigns for the indoor wideband channel using the Band Exploration and Channel Sounding (BECS) system developed by ETRI at 3.7 GHz with 100 MHz RF...
In this paper, directional MIMO measurements in an indoor office environment are presented. A 5-D ESPRIT estimation algorithm is used to extract parameters associated with discrete propagation paths, such as their azimuth of arrival, azimuth of departure, delay, and power. The estimated path parameters are grouped into clusters using the statistical K-power-means algorithm. Statistical distributions...
In this work, we provide a new throughput-based antenna selection criterion that considers the entire system design rather than only the channel state information. The performance evaluation was carried out in a measurement campaign in a common outdoor urban scenario. We present our results in terms of physical layer throughput over transmit power. In addition to diversity gains, we also see gains...
The increasing interest in MIMO (Multiple-Input Multiple-Output) systems has given rise to a prolific research activity in this topic in recent years. Several aspects have been studied, including both theoretical and practical issues. However, so far few MIMO testbeds or prototypes have been done for DVB-T or future standards. In this paper, a novel 2 times 2 MIMO testbed has been realized which has...
This paper presents a wide band 60 GHz MIMO channel measurement system using a VNA and 3-D arrays at both ends. It uses virtual antenna arrays which can be reconfigured easily. The bandwidth of the system is 3.5 GHz, which leads to a time resolution of 0.29 ns. This fine resolution is suitable for characterizing dense multipaths in indoor environments. Line of sight (LOS) and obstructed line of sight...
Code division multiplexing (CDM) based MIMO channel sounder architecture is excellent at measuring fast fading channel. In this paper, loosely synchronous (LS), Kasami and chaotic sequences are suggested as candidates for the code that will be used in CDM architecture. Among those sequences, then, the best suitable sequence for channel sounding is examined through simulation. And by proposing the...
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