A method for increasing the effective aperture of radar switch/MIMO antenna array, using a low number of transmit (Tx) and receive (Rx) army elements, according to which an array of radar physical receive (Rx)/Transmit (Tx) elements are arranged in at least two opposing Rx rows and at least two opposing Tx columns, such that each row includes a plurality of receive (Rx) elements uniformly spaced from each other and each column includes a plurality of transmit (Tx) elements uniformly spaced from each other, the array forming a rectangular physical aperture. Used as a switch array, a first Tx element from one column is activated to transmit a radar pulse during a predetermined time slot. Reflections of the first transmission are received in all Rx elements, thereby virtually replicating the two opposing Rx rows about an origin determined by the location of the first Tx element within the rectangular physical aperture. This process is repeated for all remaining Tx elements during different time slots, thereby virtually replicating the two opposing Rx rows about an origin determined by the location of each activated Tx element within the rectangular physical aperture, while each time, receiving reflections of the transmission from each Tx element in all Rx elements. This way, a rectangular virtual aperture having dimensions which are twice the dimensions of the rectangular physical aperture is paved with replicated two opposing Rx rows. This virtual aperture determines the radar beam widths and side-lobes.