A decoupling method for MIMO antennas by using a short stub

Abstract

Abstract:In recent years, MIMO technology which uses multiple antennas has been introduced in mobile terminal to increase communication capacity. However, if MIMO antennas are put closely, a strong mutual coupling occurred. Then it causes decreasing radiation efficiency and channel capacity. Therefore, reducing the mutual coupling is required. In previous study, connecting MIMO antennas by inductor L or added branch elements to antennas instead of L. In this paper, we propose a novel decoupling method by using a short stub and confirm that proposed model performed decoupling, increased radiation efficiency.

A Non-Connected Decoupling Method for Three Element MIMO Antennas by Using Short Stubs

“…This operation is the same as Ref. [11]. Hence, inductance L 2 and short stubs are operated correctly.…”

“…In Ref. [11], the decoupling method for two elements by using a short stub is proposed. We apply this decoupling method to three elements array.…”

A Dual-Band Decoupling Method of 2 Elements MIMO Antennas by Using a Short Stub and a Branch Element

“…In reference [15], decoupling is performed only using the short stub at single frequency. Moreover, references [11]- [13] use only open stubs to decouple at dual-band.…”

“…Therefore, originality of this paper compared with [11]- [13] and [15] is that short stub is attached instead of a longer branch element in trifurcation model for miniaturization of the antenna and that both the short stub and the open stub are used for dual-band decoupling.…”

A triple-band decoupling method for MIMO antennas without connection

“…2(e) shows Y 21 of the proposed model. The resonance of the short stub added at DC (0 Hz) [6], a total of four resonances appear. At 900 MHz, 1.7 GHz and 2.1 GHz, decoupling condition Y 21 ¼ 0 is achieved.…”