it would be equally plausible to connect beam port pairs b2 355 and b3 360 and to leave beam ports b1 550 and b4 565 uncombined should there be a desire to do so those having ordinary skill in this art will also readily recognize that there may nevertheless be interest in providing inward facing beam ports as shown in fig3 even if there was no intention of combining any of them or to combine beam port pairs b1 350 and b2 355 and b3 360 and b4 365 for example to centralize the routing of cables bearing the input signals through a single conduit rather than to have to provide a plurality of input conduits turning now to fig6 there is shown a plot of the array beam pattern calculated from the measured results of the 4 u00d7 4 butler matrix beamformer of the embodiment of fig4 which has two beams as the results the beam combining from b1 b4 and b2 b3 the present invention can be implemented in digital electronic circuitry or in computer hardware firmware software or in combination thereof apparatus of the invention can be implemented in a computer program product tangibly embodied in a machine readable storage device for execution by a programmable processor and methods actions can be performed by a programmable processor executing a program of instructions to perform functions of the invention by operating on input data and generating output the invention can be implemented advantageously in one or more computer programs that are executable on a programmable system.