Unit Cell Filtering and Diplexing for Electronically Scanned Arrays

Electronically scanned array (ESA) antennas are disclosed. An antenna may include an electronically scanned array (ESA) panel. The ESA panel may include a plurality of transmit/receive (T/R) modules, and each T/R module of the plurality of T/R modules may be contained within a unit cell of the ESA panel, where the unit cell has a surface area constrained by a maximum operating frequency of the ESA panel. The antenna may also include at least one radio frequency (RF) filter positioned within each particular unit cell of the ESA panel. The at least one RF filter may be configured to provide RF filtering specifically for the T/R module co-located within that particular unit cell of the ESA panel.