A 28 GHz 8×1 Un-Equal Power Divider for Reducing Side-Lobe Level of MM-Wave Array Antenna for 5G Mobile Handset

A 28 GHz 8×1 un-equal power divider with optimized power division ratio to suppress the side-lobes of array antennas for mm-wave 5G mobile handsets is proposed. To obtain the required un-equal power division ratio, 14 SMD-type ceramic capacitors with different values are inserted in the proposed design. The normalized power division ratio of the proposed un-equal power divider at output ports is 0.23:0.38:0.66:1:0.99:0.72:0.39:0.26. As a result, the SLL is improved by about 7 dB, when the proposed un-equal power divider is applied to the mm-wave 5G array antenna in comparison to using a conventional equal power divider in the same array antenna.