Synthesizing Wide-beam Array Patterns Using Phase-only Control and Trapezoidal Amplitudes for Satellite-based Internet Access

Abstract

Low Earth orbit satellite systems are capable of providing global Internet access due to their high downlink rate and low link budget. In such systems, wide beam array patterns are used to efficiently cover the required areas. In this paper, two efficient methods based on phase-only element excitation control for designing antenna arrays with required broaden beams are introduced. The first method, which is a simple algebraic approach, uses quadratic phase excitation while the amplitudes are chosen to be trapezoid. In the second method, an optimization algorithm is used to optimize the phase excitations of the array elements, while the amplitudes are still kept as a trapezoidal taper. Moreover, the use of trapezoidal-based amplitude excitations in both presented methods provides many desirable features compared to other conventional tapers. This is mainly due to the unique geometrical shape of the trapezoid taper, where the central coefficients have magnitudes of ones and the sided coefficients have decayed magnitudes. Simulations are presented to validate the proposed methods in which the beam width and maximum level of the radiated field were compared with those obtainable from the conventional standard Woodward-Lawson array.