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In this paper, we propose a new method for designing dual polarized beam switching antennas by using reconfigurable radial waveguides excited by central probes and feeding multiple radiating elements. The power distribution of the radiating elements is controlled by cylindrical electromagnetic bandgap structures made of metallic wires loaded with PIN diodes. The proposed technique allows azimuth beam switching and multiple beams, with arbitrary and well controlled polarizations, using low dc voltage. First, a new rectangular periodic structure is used as a model for analyzing the transmission and reflection coefficients for different diode states. Then, numerical and experimental results are presented for a reconfigurable radial waveguide power divider and for the radiating elements. Finally, numerical and experimental results are presented and discussed for a complete dual polarized antenna operating at wireless local area network (WLAN) 5 GHz band (5.18–5.825 GHz).

This paper considers the resource allocation problem of Space Division Multiple Access (SDMA)/ Multiple Input Single Output (MISO)/Orthogonal Frequency Division Multiple Access (OFDMA) systems. Equal power allocation (EPA) is used among subcarriers to reduce the complexity of the problem. Furthermore, a novel algorithm called proportional rate greedy (PRG) is proposed to choose users and allocate powers among selected users for each subcarrier. Such EPA-PRG algorithm can be applied to different fairness issues. From simulation, it can both achieve high throughput and ensure the fairness among users without increasing the complexity.