Cross‐polarization suppression of dual‐polarization linear microstrip antenna arrays

The cross‐polarization suppression of dual‐polarization linear microstrip antenna arrays is investigated theoretically and experimentally. Four designs of 4‐element linear microstrip antenna arrays for suppressing cross‐polarization are presented by using the pair‐wise anti‐phase feeding technique and different combinations. The simulated results are in good agreement with the experimental ones. The experimental results show that one design (design D) has much lower cross‐polarization level (about 6–10 dB) and higher isolation (about 2–4 dB) than the other three designs. The cross‐polarization level of this array is less than −27 dB and the isolation between two polarization ports is better than 34 dB in the entire frequency range of 8.74–9.5 GHz.