Quasi-phase-matching (QPM) electro-optic modulators using gap-embedded patch-antennas were proposed for improving wireless microwave-optical signal conversion. The proposed QPM devices can receive wireless microwave signals and convert them to optical signals directly. The QPM structures enable us to have twice antenna elements in the fixed device length. The device operations with improved conversion efficiency of ∼10dB were experimentally demonstrated at a wireless signal frequency of 26GHz. The proposed QPM devices were also tested to a wireless-over-fiber link.