A millimeter-wave antenna system includes: an array of radiators comprising a first radiator and a second radiator, each of the first radiator and the second radiator being configured to radiate millimeter-wave energy; and an insulator disposed at least partially between the first radiator and the second radiator and disposed and configured to intercept first near-field energy radiated by the first radiator to inhibit the first near-field energy from being received by the second radiator, and to intercept second near-field energy radiated by the second radiator to inhibit the second near-field energy from being received by the first radiator, the insulator being configured to reflect the first near-field energy away from the first radiator and away from the second radiator and to reflect the second near-field energy away from the first radiator and away from the second radiator.