Design of multi-patch planar filtering antenna

In this paper, a planar filter patch microstrip antenna based on multi-patch is proposed. The antenna has the advantages of low profile, high gain, wide band and high selectivity of band edges. The antenna is composed of a rectangular patch antenna, a pair of symbiotic patches, four parasitic patches and six symbiotic strips.By adding parasitic strips around the driven patch can excite new resonances at high frequency, while making the high frequency band edge selectivity better due to the generation of radiation null near high frequency. By embedding two symbiotic strips along the Y-axis of the driven radiation patch, a new resonance and radiation null at low frequency can be generated. Finally, six rectangular patches were introduced along the X-axis of the driven radiating patch to improve the in-band matching. The proposed antenna is physically processed, and the measured results are consistent with the simulation results. IBW is 16.26% (3.39-3.99 GHz), and the average gain is greater than 9.5dBi.The out-of-band gain suppression level on both sides can reach 10dB.