Optimal Design Method of MIMO Antenna Directivities and Corresponding Current Distributions by Using Spherical Mode Expansion

Maki ARAI; Masashi IWABUCHI; Kei SAKAGUCHI; Kiyomichi ARAKI

doi:10.1587/transcom.2016EBP3402

Optimal Design Method of MIMO Antenna Directivities and Corresponding Current Distributions by Using Spherical Mode Expansion

Maki ARAI, Masashi IWABUCHI, Kei SAKAGUCHI, Kiyomichi ARAKI

Full Text Views

0

Share
Cite this

Summary :

This paper proposes a new methodology to design optimal antennas for MIMO (Multi-Input Multi-Output) communication systems by using spherical mode expansion. Given spatial channel properties of a MIMO channel, such as the angular profile at both sides, the optimal MIMO antennas should provide the largest channel capacity with a constraint of the limited implementation space (volume). In designing a conventional MIMO antenna, first the antenna structure (current distribution) is determined, second antenna directivity is calculated based on the current distribution, and thirdly MIMO channel capacity is calculated by using given angular profiles and obtained antenna directivity. This process is repeated by adjusting the antenna structure until the performance satisfies a predefined threshold. To the contrary, this paper solves the optimization problem analytically and finally gives near optimal antenna structure (current distribution) without any greedy search. In the proposed process, first the optimal directivity of MIMO antennas is derived by applying spherical mode expansion to the angular profiles, and second a far-near field conversion is applied on the derived optimal directivity to achieve near optimal current distributions on a limited surface. The effectiveness of the proposed design methodology is validated via numerical calculation of MIMO channel capacity as in the conventional design method while giving near optimal current distribution with constraint of an antenna structure derived from proposed methodology.

Publication: IEICE TRANSACTIONS on Communications Vol.E100-B No.10 pp.1891-1903

Publication Date: 2017/10/01

Publicized: 2017/03/15

Online ISSN: 1745-1345

DOI: 10.1587/transcom.2016EBP3402

Type of Manuscript: PAPER

Category: Antennas and Propagation

Authors

Maki ARAI
  Tokyo Institute of Technology
Masashi IWABUCHI
  Tokyo Institute of Technology
Kei SAKAGUCHI
  Tokyo Institute of Technology
Kiyomichi ARAKI
  Tokyo Institute of Technology

Keyword

MIMO, antenna directivity, antenna structure, current distribution, spherical mode expansion, capacity maximization

Cite this

Copy

Maki ARAI, Masashi IWABUCHI, Kei SAKAGUCHI, Kiyomichi ARAKI, "Optimal Design Method of MIMO Antenna Directivities and Corresponding Current Distributions by Using Spherical Mode Expansion" in IEICE TRANSACTIONS on Communications, vol. E100-B, no. 10, pp. 1891-1903, October 2017, doi: 10.1587/transcom.2016EBP3402.
Abstract: This paper proposes a new methodology to design optimal antennas for MIMO (Multi-Input Multi-Output) communication systems by using spherical mode expansion. Given spatial channel properties of a MIMO channel, such as the angular profile at both sides, the optimal MIMO antennas should provide the largest channel capacity with a constraint of the limited implementation space (volume). In designing a conventional MIMO antenna, first the antenna structure (current distribution) is determined, second antenna directivity is calculated based on the current distribution, and thirdly MIMO channel capacity is calculated by using given angular profiles and obtained antenna directivity. This process is repeated by adjusting the antenna structure until the performance satisfies a predefined threshold. To the contrary, this paper solves the optimization problem analytically and finally gives near optimal antenna structure (current distribution) without any greedy search. In the proposed process, first the optimal directivity of MIMO antennas is derived by applying spherical mode expansion to the angular profiles, and second a far-near field conversion is applied on the derived optimal directivity to achieve near optimal current distributions on a limited surface. The effectiveness of the proposed design methodology is validated via numerical calculation of MIMO channel capacity as in the conventional design method while giving near optimal current distribution with constraint of an antenna structure derived from proposed methodology.
URL: https://globals.ieice.org/en_transactions/communications/10.1587/transcom.2016EBP3402/_p

Copy

@ARTICLE{e100-b_10_1891,
author={Maki ARAI, Masashi IWABUCHI, Kei SAKAGUCHI, Kiyomichi ARAKI, },
journal={IEICE TRANSACTIONS on Communications},
title={Optimal Design Method of MIMO Antenna Directivities and Corresponding Current Distributions by Using Spherical Mode Expansion},
year={2017},
volume={E100-B},
number={10},
pages={1891-1903},
abstract={This paper proposes a new methodology to design optimal antennas for MIMO (Multi-Input Multi-Output) communication systems by using spherical mode expansion. Given spatial channel properties of a MIMO channel, such as the angular profile at both sides, the optimal MIMO antennas should provide the largest channel capacity with a constraint of the limited implementation space (volume). In designing a conventional MIMO antenna, first the antenna structure (current distribution) is determined, second antenna directivity is calculated based on the current distribution, and thirdly MIMO channel capacity is calculated by using given angular profiles and obtained antenna directivity. This process is repeated by adjusting the antenna structure until the performance satisfies a predefined threshold. To the contrary, this paper solves the optimization problem analytically and finally gives near optimal antenna structure (current distribution) without any greedy search. In the proposed process, first the optimal directivity of MIMO antennas is derived by applying spherical mode expansion to the angular profiles, and second a far-near field conversion is applied on the derived optimal directivity to achieve near optimal current distributions on a limited surface. The effectiveness of the proposed design methodology is validated via numerical calculation of MIMO channel capacity as in the conventional design method while giving near optimal current distribution with constraint of an antenna structure derived from proposed methodology.},
keywords={},
doi={10.1587/transcom.2016EBP3402},
ISSN={1745-1345},
month={October},}

Copy

TY - JOUR
TI - Optimal Design Method of MIMO Antenna Directivities and Corresponding Current Distributions by Using Spherical Mode Expansion
T2 - IEICE TRANSACTIONS on Communications
SP - 1891
EP - 1903
AU - Maki ARAI
AU - Masashi IWABUCHI
AU - Kei SAKAGUCHI
AU - Kiyomichi ARAKI
PY - 2017
DO - 10.1587/transcom.2016EBP3402
JO - IEICE TRANSACTIONS on Communications
SN - 1745-1345
VL - E100-B
IS - 10
JA - IEICE TRANSACTIONS on Communications
Y1 - October 2017
AB - This paper proposes a new methodology to design optimal antennas for MIMO (Multi-Input Multi-Output) communication systems by using spherical mode expansion. Given spatial channel properties of a MIMO channel, such as the angular profile at both sides, the optimal MIMO antennas should provide the largest channel capacity with a constraint of the limited implementation space (volume). In designing a conventional MIMO antenna, first the antenna structure (current distribution) is determined, second antenna directivity is calculated based on the current distribution, and thirdly MIMO channel capacity is calculated by using given angular profiles and obtained antenna directivity. This process is repeated by adjusting the antenna structure until the performance satisfies a predefined threshold. To the contrary, this paper solves the optimization problem analytically and finally gives near optimal antenna structure (current distribution) without any greedy search. In the proposed process, first the optimal directivity of MIMO antennas is derived by applying spherical mode expansion to the angular profiles, and second a far-near field conversion is applied on the derived optimal directivity to achieve near optimal current distributions on a limited surface. The effectiveness of the proposed design methodology is validated via numerical calculation of MIMO channel capacity as in the conventional design method while giving near optimal current distribution with constraint of an antenna structure derived from proposed methodology.
ER -