Nowadays, polarization diversity scheme has been adopted in place of space
diversity since it reduces the number of
antennas in comparison with space diversity scheme and hence lowers the cost of antennas and their supporting BTS towers. The diversity gain from polarization diversity is maximized if the dual-polarized antenna has receive diversity ports that receives radiation in a cross-polarized fashion over the desired coverage area with equal field strengths and deliver it to the diversity network. Like space diversity, polarization diversity relies on the decor relation of the two receive ports to achieve diversity gain. It is customary to use a slant-45 polarization diversity antenna which consists of two independent linearly polarized dipoles or micro strip patch elements. Therefore, it is not guaranteed to deliver two nearly equal power signals to the diversity network. In this work, we have used two independent left and right circularly polarized elements instead of two independent linearly polarized elements to guarantee equal received signal power to be delivered to the diversity network. To make comparison between this new type antenna and ordinary one, correlation factor and SNR of both types are calculated. It is shown that this new type antenna, not only support common properties but also guarantee nearly equal signal power input to the diversity network.
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