A new framework for the analysis of multiple-input multiple-output (MIMO) wireless systems is introduced to account mutual coupling effects in antenna arrays. The multiport interactions at transmit and receive are characterized by representing channel using a scattering parameter matrix. power constraint that limits average radiated also introduced. capacity MIMO system with defined as maximum information vectors over all possible signaling loading. Full-wave electromagnetic simulations...

Evidence that the 'Kronecker' model underestimates channel capacity of an 8×8 multiple input, output (MIMO) system in indoor non-line-of-sight (NLOS) scenarios is presented. Moreover, does not render multipath structure correctly, which cause for systematic mismatch.

Detailed performance assessment of space-time coding algorithms in realistic channels is critically dependent upon accurate knowledge the wireless channel spatial characteristics. This paper presents an experimental measurement platform capable providing narrowband transfer matrix for communications scenarios. The system used to directly measure key multiple-input-multiple-output parameters indoor environment at 2.45 GHz. Linear antenna arrays different sizes and construction with up ten...

This paper demonstrates the ability of a physically based statistical multipath propagation model to match capacity statistics and pairwise magnitude phase distributions measured 4 /spl times/ 10 narrow-band multiple-input multiple-output data (MIMO) at 2.4 GHz. The is compared simpler models on multivariate complex normal distribution with either envelope or power correlation. comparison facilitated by computing channel element covariance matrices for fixed sets statistics....

A new analysis of mutually coupled diversity antenna systems is presented that includes the effects coupling on radiation pattern and received power. This analysis, based upon network scattering parameters, makes use singular value decomposition to both specify characteristics analyze terminated networks. The approach facilitates a simplified proof multiport conjugate matching condition as well development expressions for performance function various impedance terminations. Application...

There is growing interest in wireless security methods that provide strong or even perfect secrecy by taking advantage of features the physical propagation channel. In advantage-based methods, high channel quality an average opportunistic sense exploited between two legitimate nodes, such nonzero capacity can be achieved. Since require bounds on eavesdropper channel, they are somewhat impractical. Secret key generation based tracking evolution time division duplex systems a more attractive...

This paper provides an analytical framework useful for assessing the use of all six electric and magnetic electromagnetic field polarizations multiantenna communications systems. The approach uses a mapping between induced signal currents received in order to formulate diversity interpretation six-polarization problem. Application simple, yet representative, channel model demonstrates that full multipath elevation azimuthal angle spread, communication modes are theoretically possible....

Constructing the capacity bound of a multiple-input multiple-output wireless system is often performed by assuming specified antenna configurations and propagation environment determining signaling strategy which maximizes throughput. This paper extends this approach to further determine optimal characteristics maximize for scenario, with resulting representing ultimate maximum achievable value if design are used. In approach, spatially-continuous transmit currents receive fields represented...

MIMO wireless systems employing antenna arrays with close inter-element spacings exhibit a high degree of mutual coupling. In this case, the channel transfer matrix is function matching network employed for transmitting and receiving. Existing capacity expressions are inappropriate, since maximum information will depend on element loading. This paper develops new expression that includes effect coupling matching. Two simple noise models realistic high-frequency circuits introduced. Capacity...

This paper presents measured data from a narrowband multiple-input multiple-output (MIMO) channel probe in an indoor office/laboratory environment. The system employs ten transmit and receive antennas computes the 10 /spl times/ matrix at 2.45 GHz every 80 milliseconds. We use to study statistical behavior of coefficients resulting capacity. also demonstrate ability simple statistically based physical model accurately represent behavior. results this are compared more conventional models...

Multiantenna systems such as devices for multiple-input-multiple-output (MIMO) communication can theoretically use array superdirectivity to optimally exploit the propagation channel. In traditional analyses of MIMO systems, is not observed due commonly applied constraint that limits excitation current magnitudes. However, when an electromagnetically appropriate on power radiated by applied, computed capacity include effects transmit superdirectivity. A similar result occurs at receiver...

The temporal variation in measured multiple-input multiple-output (MIMO) wireless channels with moving communication nodes is analyzed. A wide-band 8 times sounder employed to measure the response of indoor and outdoor at 2.55 5.2 GHz. rate channel then quantified terms information theoretic metrics that indicate loss quality as transmit receive state becomes increasingly outdated. Finally, these are used investigate ability two different modeling strategies-a random matrix model a physical...

Due to the complexity of multiple-input-multiple- output (MIMO) wireless channels, direct measurement is main viable option for accurate characterization. Details on a new low-cost wideband channel sounder are presented, which was mainly constructed from conventional instruments and components. This switched architecture system similar commercial sounders has modest cost (< US$ 50000). The operates in 2- 8-GHz range with up 100 MHz instantaneous bandwidth supports eight transmitters...

When establishing secret encryption keys using estimates of the reciprocal wireless channel, number key bits that can be generated for a static or slowly varying propagation environment enhanced by randomly changing radiation properties reconfigurable antenna. However, prior studies this approach have been limited and not considered high degree antenna reconfigurability. This paper uses simulations experimental measurements to characterize impact complexity on performance establishment in...

The paper presents a new framework for the information-theoretic analysis of multipath multiple-input multiple-output (MIMO) wireless communications channels. approach defines an upper bound on transmission that depends physical propagation scenario and transmit/receive antenna apertures but is otherwise independent properties. Transmit sources receive sensors are abstracted in terms spatial basis functions. "intrinsic capacity" channel defined as maximum mutual information transmit vectors...

A common practice when analyzing systems using multiple antennas at both ends is to focus on the multipath properties and normalize SNR out of channel matrix. This paper studies relationship between signal strength richness indoor measurements taken Brigham Young University campus. It found that can be strongly corrected. Hence, some caution needed normalizing in system performance studies. Furthermore, for unnormalized channel, capacity usually rises moving from NLOS into LOS since loss...

A method that exploits the autocorrelation of transmission signals for primary user detection in cognitive radio is proposed. closed-form analysis presented and compared with Monte Carlo simulations. Analytical simulation results indicate provides significant improvement probability moderate SNR scenarios where fast sensing required. Simulation better performance fading environment collaborative as well.

The equivalent circuit model of a general PEC antenna array is derived, based on rigorous method moments (MOM) formulation, indicating that network analysis exact from the standpoint electromagnetic wave theory. It found parameters (Z, Y, or S-parameters) for transmit mode can be used prediction receive-mode response. Numerical and experimental examples illustrate validity analytical results.

Traditional forestry, ecology, and fuels monitoring methods can be costly error-prone, are often used beyond their original assumptions due to difficulty or unavailability of more appropriate methods. These traditional tend rigid may not useful for detecting new ecological changes required data at modern levels precision [[1]Lindenmayer D.B. Likens G.E. Adaptive monitoring: a paradigm long-term research monitoring.Trends Ecol. Evol. 2009; 24:...

This paper presents a new framework for the information-theoretic analysis of multipath multiple-input multiple-output (MIMO) wireless communications channels. The approach defines an upper bound on transmission that depends physical propagation scenario and transmit/receive antenna apertures but is otherwise independent properties. Transmit sources receive sensors are abstracted in terms spatial basis functions. intrinsic capacity channel defined as maximum mutual information transmit...

Accurate characterization of multiple-input multiple-output (MIMO) fading channels is an important prerequisite for the design multiantenna wireless-communication systems. In this paper, a single-bounce two-ring statistical model time-varying MIMO flat proposed. model, both base and mobile stations are surrounded by their own ring scatterers. For proposed closed-form expression spatio-temporal cross-correlational function between any two subchannels derived, assuming scattering. The new...

This paper presents results from an experimental platform designed to measure the transfer matrix for indoor and outdoor multiple-input multiple-output (MIMO) channels with up 16 transmit receive antenna elements. Key aspects of hardware system data post-processing techniques are provided. A variety measurements have been taken at 2.45 GHz in a typical environment. The collected processed highlight channel features, including statistical distributions elements inherent capacity wireless MIMO...