On Antenna Design Objectives and the Channel Capacity of MIMO Handsets (original) (raw)

Capacity of the mobile MIMO channel for a small wireless handset and user influence

The 13th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, 2002

We obtained results on the capacity of a mobile MIMO channel and on the influence of the user. Measurements were done in a configuration with three distributed transmitters equipped with single antennas and with a small wireless handset with four antennas, creating a 4Rx x 3Tx configuration. We express the quality of the radio channel in terms of the Effective Degree of Freedom (EDOF)[1]. From our measurement it follows that fitting a small handset with multiple antennas still makes sense in an outdoor-to-indoor mobile MIMO scenario. The channel capacity can be excellent, comparable with fully uncorrelated Rayleigh fading branch signals. However, on average the user should be satisfied with less favourable conditions amounting to a loss in EDOF of 0.16 at 50% Complementary Cumulative Distribution Function (CCDF) level. Systems operating without power control will suffer from an extra degradation in EDOF of 0.10 with an increased spread in channel quality both at the high and low end of the EDOF curve.

User Influence on MIMO Channel Capacity for Handsets in Data Mode Operation

IEEE Transactions on Antennas and Propagation, 2000

The current paper concerns realistic evaluation of the capacity of the MIMO channel between a BS and handheld device, such as a PDA or smartphone, held in front of the user's body (data mode). The work is based on measurements of the MIMO channel between two widely separated BSs in a microcellular setup, and six handsets located in an indoor environment. The measurements are done simultaneously in both the 773.5-778.5 MHz and 2250-2350 MHz bands, and from the two BSs. The handsets are realistic types and were measured both in free space and with twelve different users, using both one and two hands. The random capacities of the channels are evaluated in terms of outage capacity. For an SNR of 10 dB, median capacities in free space of about 4.4-4.7 bit/s/Hz for the low band and about 3.3-3.8 bit/s/Hz for the high band were found. The mean decrease in outage capacity due to the user was found to be up to about 2.2 bit/s/Hz, depending on the band and handset. More results are presented in the paper.

Correlation analysis based on MIMO channel measurements in an indoor environment

IEEE Journal on Selected Areas in Communications, 2003

Multiple-input-multiple-output (MIMO) systems have the potential to achieve very high capacities, depending on the propagation environment. Capacity increases as signal correlation decreases. We present the measurements of a MIMO system under strong and weak line-of-sight conditions. The system capacity decreases as the distance from the transmitter increases. Indeed the transmitter correlation increases as the distance increases. The receiver correlation is lower than the transmitter correlation under both propagation conditions.

MIMO Channel Correlation and System Capacity Analysis

2015

Over the last two decades, wireless communication services and applications worldwide have witnessed exponential growth with corresponding progression in subscribers’ population but without resultant increase in bandwidth required for their effective functionality. Solution to this challenge has led to the adoption of multiple-input–multiple-output (MIMO) systems prevalent in the emerging wireless communication technologies because of their high capacity. This paper investigates the capacity distribution of MIMO systems with arbitrary correlation among the antennas in frequency-flat Rayleigh environments. In addition, the capacity of spatially correlated MIMO channels is evaluated with and without channel state information (CSI) at the transmitter. Through simulation, this study observed that channel capacity increases as signal correlation decreases, while bit error rate increases with increase in signal correlation. Consequently, as the channel becomes progressively correlated in ...

Design Considerations of MIMO Antennas for Mobile Phones

PIERS Online, 2008

The paper presents a new modeling and design concept of antennas using polarization diversity of 2 × 2 and 3 × 3 Multiple Input Multiple Outputs (MIMO) system that is proposed for future mobile handsets. The channel capacity is investigated and discussed over Raleigh fading channel and compared to a linear/planner antenna array MIMO channel. The capacity is also discussed over three types of power azimuth spectrums. The results are compared to the constraints capacity limits in which the maximum capacity observed.

Characterization of the Indoor/Outdoor to Indoor MIMO Radio Channel at 2.140 GHz

Wireless Personal Communications, 2005

In this paper the radio channel characteristics of the 8 × 4 MIMO system consisting of a base station and a small terminal equipped with multiple antennas for indoor-indoor and outdoor-indoor scenarios are presented. We study the large-scale variation and small-scale characteristics of the measured channel coefficients. Although the mean received power is very much dependent on the measured location, the channel capacity seems to be unchanged when the receiver's location is altered. The data collected from different scenarios (e.g. measurement locations, antenna setting) were used to investigate the advantage of having the knowledge of the channel at both ends of the transmission link. It is shown that using the water filling algorithm there is indeed an increase in the channel capacity. At low SNR, the benefit of knowing the channel at both link ends observed in the measurement data is much higher than which can be obtained in the channel matrix with usual assumption on identical independently distributed components. Using the small-scale and large-scale information in the formulation of the channel capacity we show that in our measurement, the variation of the mean received power has a greater influence on the change of the overall system performance than the change in the environmental multipath scattering property.

Investigation of MIMO channel correlation and capacity based on partial embedded RF measurements

Canadian Conference on Electrical and Computer Engineering 2004 (IEEE Cat. No.04CH37513)

This letter explores the influence of curved subway tunnel on multiple-input-multiple-output (MIMO) channel. In order to study in detail and comprehensively, extensive simulations have been carried out with different curvatures, receiver positions and antenna configurations. Ray-tracing was utilized to obtain the MIMO channel matrices at 1.8GHz. The influence of curved tunnel has been highlighted by comparing with that of straight tunnel in terms of a statistical analysis of correlation between antennas of receiver, singular values of channel transfer matrix and channel capacity. The calculation of channel capacity is based on both a constant signal-to-noise ratio (SNR) and a fixed transmitted power. The results provide reference for the other relevant research and engineering community in the future.

Performance estimation for MIMO channel

2006 International Biennial Baltic Electronics Conference, 2006

In this paper we present the performance estimation for mobile environment wideband radio channel based on multiple antenna system. Wireless communications systems equipped with multiple antennas at both the transmitter and receiver have been widely stated as an important technology to improve performance. These so-called multiple-input multiple-output (MIMO) systems can increase diversity to reduce performance degradation due to the fading phenomenon in wireless channels. Using statistical signal processing approach Rayleigh, Rician and Nakagami fading scenarios are analyzed. Obtained results show slightly better performance for mean received power in Nakagami environment compared to Rician broadband radio channel in the weak interference conditions.

Experimental Evaluation of the Mobile Radio Channel Capacity in the 2.48 GHz Band

Journal of Microwaves, Optoelectronics and Electromagnetic Applications, 2017

This paper deals with the effect of the Single-Input Multiple-Output spatial diversity on the OFDM mobile radio signal propagating in an urban channel. From measurements performed in Rio de Janeiro city, Brazil, by using two receiving antennas at diversity, the calculated capacity presented an improvement when compared to the individual one.

MIMO channel capacity of a measured indoor radio channel at 5.8 GHz

Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154), 2000

Herein, an analysis of indoor environment Multiple-Input-Multiple-Output measurements in the 5.8 GHz band is performed and the possible increase in capacity, utilizing multiple transmitters and receivers is examined. The investigation shows that in the measured indoor environment, the scattering is suficiently rich to provide substantial link capacity increases. Furthermore, the effect of intra-element element spacing o n the channel capacity is studied, Finally the possible Hiper-LAN/2 MIMO channel capacity, based o n the measurements, is examined. , 0-7803-65 14-3/00/$10.0002000 IEEE