on the first two rows of radiating elements to provide a horizontal horizontal module configuration in this configuration a horizontally horizontally polarized radiation pattern is provided from the antenna array similarly the first and second module 43 and 44 can be lowered by one row to provide a horizontal vertical module configuration wherein the radiation pattern is horizontally vertically polarized a vertically vertically polarized radiation pattern can be also be obtained by lowering the first and second modules to the last two rows of the array 45 and 46 to the vertical vertical module configuration shown in fig4 b referring now to fig5 we have shown the power distribution network of fig3 b in particular as indicated previously the power distribution network 34 which when provided with a predetermined number of transmission lines forming a predetermined pattern can give a normalized signal at each output port for example given an input signal at input port 35 a normalized output amplitude is provided at the six 6 output ports 30 thus assuming we have an input signal of the order of 6 watts at input port 35 each output port 30 will produce a normalized output signal equal to u2159 of the amplitude of the input signal i e 1 watt referring now to fig6 we have shown another power distribution network 50 wherein the output amplitude at each.