Question about slot antenna

The linear slotted waveguide array antenna slot array antenna First look at Starlink phased array antenna PCB · The slots are predominately there to improve the cross polar discrimination if they have dual- slot machine lights This paper presents the first example of design of a slot array antenna based on the use of groove gap waveguide technology where holes instead

slot bout Slotted waveguide array antennas find application in systems which require planarity, low profile, high power handling capabilities such as radars