Mode-Counteraction Based Self-Decoupling in Circularly Polarized MIMO Microstrip Patch Array

作者：Lai, Qi Xuan; Pan, Yong Mei^*; Zheng, Shao Yong

来源：IEEE Transactions on Antennas and Propagation, 2022, 70(10): 9337-9346.

DOI：10.1109/TAP.2022.3184508

• Circularly polarized (CP) antenna
• microstrip patch antenna (MPA)
• multi-input multi-output (MIMO) antenna
• mutual coupling
• self-decoupling

A mode-counteraction-based self-decoupling method is proposed for the circularly polarized (CP) multi-input multi-output (MIMO) microstrip patch antenna (MPA) array. The array simply consists of two identical diagonal-fed rectangular MPAs, without any extra decoupling structure. It is found that by properly adjusting the patch dimensions and feeding positions, the orthogonal TM1.0 and TM0.1 modes can be simultaneously excited in the active MPA to generate the CP field. Meanwhile, the coupled E-fields of the two modes in the adjacent passive MPA can counteract each other, generating a null-field region. When the feeding probe of the passive MPA is placed within the null-field region, no signal can be received at the port, and consequently, an extremely low mutual coupling of -59.4 dB is achieved, without scarifying any other radiation performance of the MPA. In addition, this self-decoupling method is also applicable to other types of MPA arrays and four-element MPA arrays, exhibiting great versatility and extensibility.

• 单位
  中山大学