A polarimetric line-of-sight channel model for MIMO satellite communications

Abstract

Spatial multiple-input multiple-output (MIMO) offers increased rate and/or reliability in rich scattering environments such as that of a multipath non-line-of-sight (NLOS) channel. In line-of-sight (LOS) dominated conditions, spatial diversity is reduced.Dual polarisation signalling has been shown to successfully exploit polarisation diversity when LOS is dominant. For satellite systems, such state-of-the-art dual-polarisation techniques do not currently account for the 3D geometry of the link, and specifically the polarisation mismatch from misalignment of the antenna elements. Performance loss due to the mismatch in antenna orientation can be overcome by using 3D polarimetric antennas at both the transmitter and receiver.In this paper, we present a novel polarimetric LOS MIMO channel model by combining satellite geometry, the Friis equation and polarisation mismatch. Our emphasis is on polarisation mismatch and how this varies over the field-of-view (FOV). Our model offers the opportunity for 3D polarimetric signalling techniques to deliver enhanced and more consistent link performance over the FOV.

Geometric polarization and Faraday effects for VHF satellite communication links

“…We are now ready to form our equivalent channel matrix for the link by scaling at the Tx and Rx such that the power transferred is consistent with the Friis formula including polarization mismatch [4], [8]. Here we give the formula for just one polarization dimension at each of the Tx and Rx corresponding to antennasr andẑ: (18) where g r (θ r , φ r ) and g z (θ z , φ z ) are the directive gain patterns derived from the radiation functions f r (k, θ r , φ r ) and f z (k, θ z , φ z )) [8], [10], and λ 2 /(4πd) 2 is the free-space path loss (FSPL).…”

“…Without accounting for Faraday rotation, a 3D LOS model can be derived using the Friis equation for power transfer including polarization mismatch [4]. Since this approach cannot accommodate Faraday rotation, we adopt a different approach in this paper.…”

Offshore Electromagnetic Spectrum Distribution Prediction Model Based on Ray Tracing Method and PM Wave Spectrum

“…The height of the intersection from the horizontal plane is defined as h(x). When η(x) < 0 • , (8) can be modified to According to (17), the h(x) can be expressed as…”

“…Polarization mismatch between transmitting antenna and receiving antenna can affect the quality of the communication. References [16], [17] study the effect of antenna polarization mismatch on the quality of microwave communication. Antenna tilting in a offshore environment results in polarization mismatch between the antennas.…”

Tri‐orthogonal polarization diversity reception for non‐geosynchronous satellite orbit ionospheric channels

“…We may introduce signal transfer between T and R as proportional to the square root of power transfer through each subchannel [37]. In addition, a phase matrix is required that introduces the change in phase along a sub-channel as a result of path delay, Doppler shift and relative antenna offsets at both the receiver and transmitter.…”