A compact stacked bidirectional antenna is presented for dual-polarized 2.4 GHz WLAN applications in this paper. The antenna consists of an orthogonal coupling feed driver and stacked director array, with the overall size 50×50×160 mm3. Dual-polarization is excited by the orthogonal coupling line, and the director array contributes to the bidirectional radiation pattern. Both the coupling feed driver and directors are printed on FR4 substrate and supported by plastic pillars. The measured bandwidth of the two ports are 2.33-2.62 GHz (11.8%) and 2.32-2.64 GHz (13%) under the condition of VSWR less than 2. The isolation between two ports are lower than -20 dB. The peak gains along one radiation direction are 9.65 dBi and 9.30 dBi for each port, with highly symmetric bidirectional beam pattern. The proposed antenna is compact and stable, and suitable for bidirectional 2.4 GHz WLAN applications.
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