On spherical vs. plane wave modeling of line-of-sight MIMO channels

Geometry-Based Statistical Modeling of Non-WSSUS Mobile-to-Mobile Rayleigh Fading Channels

“…1.7.3]. This simplification is valid in the context of short-range vehicular communication for propagation over small local areas, provided that the far-field condition holds [21]. 1 In the PWP framework, the path length of a traveling wave is approximated by the scalar projection p, u , where p describes the observer's position relative to the source's location, and u is a unit vector that points at the direction of propagation, as illustrated in Fig.…”

Is Orbital Angular Momentum (OAM) Based Radio Communication an Unexploited Area?

“…We pay special attention to the singular value decomposition (SVD) based derivation of channel capacity for MIMO systems [8], when applied to MIMO systems under free-space propagation conditions. Spatial multiplexing under free-space conditions may seem like a contradiction, but this very concept has been investigated in various forms for almost a decade [9] [10] [11] [12]. When restricting ourselves to using circular antenna arrays, the SVD-based analysis in combination with properties of circulant matrices [13] [14] can deliver the same beam-forming and the same OAM properties as in [1] [2].…”

Modelling line-of-sight coupled MIMO systems with generalised scattering matrices and spherical wave translations

“…It is especially suited for short-range communications, where the spherical vector nature of the propagating field plays a major role like WLAN MIMO systems [4] and in the case that mutual coupling effects are significant at the transmitting and/or receiving arrays and eventually when the antennas are in the proximity of scatterers. The inclusion of these features is done through the GSM characterisation of every antenna and rotation and translation properties of spherical waves.…”

“…When the transmitting and receiving arrays are far away from each other and from scatterers, this does not pose any problems. However, the real spherical nature of the propagating field may exert a significant influence on the characteristics of shortrange MIMO systems [3,4]. In this Letter, we propose an EM-based MIMO system model based on rotation and translation coefficients of spherical modes [5], which describes the true spherical nature of the wave propagation and in addition considers mutual coupling.…”