Patent ID: RE44332

Claim:
An A base station array antenna assembly having an operating frequency and a vertical radiation pattern with a main lobe axis defining a downtilt angle with respect to the earth's surface, the antenna assembly comprising: a plurality of antenna means in first, second, and third antenna groups physically disposed along a backplane, the backplane having a longitudinal axis along which the antenna means are disposed; differential phase adjustment means disposed electrically connected on a path of transmission line means between the second first and third antenna groups configured to simultaneously advance a phase angle of a signal to one of said second first and third antenna groups and delay the phase angle of said signal to the other of said second first and third antenna groups; such that adjustment of the phase adjustment means results in variation of the vertical radiation pattern downtilt angle between a first fixed position and a second fixed position; said differential phase adjustment means including coupling means arcuately moveable along an arcuate section of said transmission line means to cause said simultaneous advance of a phase angle of a signal to one of said first and third antenna groups and a delay of the phase angle of said signal to the other of said first and third antenna groups .