The Feasibility of Two One-Parameter Polarization Control Methods in Satellite Communications

The orthogonal polarization techniques will be widely used in satellite communications due to its efficient utilization of the spectrum, but the feasibility of different methods to compensate for the cross-polarization at ground stations will be essential for the applicability of the techniques. Although complicated four-variable systems have been designed by many groups, two simple one-parameter methods have been proposed recently. The first, rotational compensation, simply rotates the linear polarization directions of the receiving antenna to maximize XPD; the second, quadrature cancellation, simply injects quadrature cancelling signals. This paper studies the feasibility of these two methods in terms of system designer's viewpoints. A correlation approach is used to estimate the achievable XPD values for different situations including rain, ice particles, and Faraday rotation. The system availability and cost considerations are analyzed using a possible tradeoff between CNR and XPD values. The control errors and stability problems are also discussed. The results indicate that there exist many situations in which these one-parameter methods are feasible and attractive and provide possible solutions for designers desiring effective, low-cost receiving stations with satisfactory performance.