Simultaneous multiple beam antenna array matrix and method thereof

In a simultaneous multiple beam antenna array matrix including a Butler matrix having eight input ports and eight output ports, a method of maximizing the efficiency for a side lobe level at least 15 dB down comprising the steps of:

• (a) shifting the phases of signals at the eight output ports in a fixed phase progression of approximately 22.5.degree. to provide phase progressions of approximately 0.degree., .+-.45.degree., .+-.90.degree., .+-.135.degree. and 180.degree. at the eight output ports;
• and
• (b) combining inputs to alter the phase progressions to approximately .+-.35.degree. and .+-.105.degree..

An antenna array matrix for simultaneously providing multiple beams, said matrix comprising:

• (a) a Butler matrix having 3.sup.m .multidot.2.sup.n input ports and 3.sup.m .multidot.2.sup.n output ports, where m and n are any whole positive integer either of which may include zero;
• (b) phase shifting means connected to the 3.sup.m .multidot.2.sup.n output ports of said Butler matrix for introducing a phase shift in a fixed phase progression of approximately 180.degree. divided by the number of output ports;
• (c) means for combining the 3.sup.m .multidot.2.sup.n input ports for providing resultant output beams that have an amplitude taper resulting in a predetermined amplitude of sidelobes with approximately a maximization of efficiency.

An antenna array matrix for simultaneously providing multiple beams, said matrix comprising a Butler matrix having at least 3 input ports and a similar number of output ports, said Butler matrix including at least one six port junction with first and second 3 dB quadrature couplers, a 4.78 dB quadrature coupler, and fixed 90.degree. phase shift means, one output port of said first 3 dB coupler being coupled to an input port of said second 3 dB coupler through said 90.degree. phase shift means, one output port of said first 3 dB coupler being coupled to an input port of said 4.78 dB coupler, one output port of said 4.78 dB coupler being coupled to a second input port of said second 3 dB coupler, one output port of said second 3 db coupler forming an output port of said six port junction, a second output port of said second 3 dB coupler forming a second output port of said six port junction, and a second output port of said 4.78 dB coupler forming the third output port of said six port junction.

An antenna array matrix comprising a two dimensional six port junction including first and second 3 dB quadrature couplers and a 4.78 db quadrature coupler connected by means of phase shifting lines to provide a 120.degree. phase progression and equal power division.