Patent ID: 6452568
Filing Date: 2002-09-17
Classification: H01Q

Abstract:
A dual array antenna, comprising:a first array comprising a first plurality of spiral-like antenna elements interconnected together on a first surface, said first plurality including at least first and second spiral-like antenna elements connected together, said first array transmitting and receiving right hand circularly polarized (RHCP) signals; and a second array comprising a second plurality of spiral-like antenna elements interconnected together on a second surface, said second plurality including third and fourth spiral-like antenna elements, with said first plurality not being interconnected with said second plurality, said second array transmitting and receiving left hand circularly polarized (LHCP) signals, at least said transmitted RHCP signals of said first array and at least said transmitted LHCP receive signals of said second array are transmitted with reduced coupling between said first and second arrays when said RHCP signals and said LHCP signals are transmitted simultaneously, wherein said first array does not essentially transmit LHCP signals when said second array transmits said LHCP signals and said second array does not essentially transmit said RHCP signals when said first array transmits RHCP signals, whereby isolation between said RHCP signals and said LHCP signals is enhanced; wherein said first, second, third and fourth spiral-like antenna elements have first, second, third and fourth feed points, respectively, and said third and fourth feed points of said third and fourth spiral-like antenna elements are offset from said first and second feed points of said first and second spiral-like antenna elements.