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Coupling Minimization of Dual-Port Meta-Surface MIMO Antenna With Pin Vias for IoT Technology
(2025-01-01)
Supreeyatitikul, Nathapat
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Boonpoonga, Akkarat
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Phongcharoenpanich, Chuwong
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Lerttheerachanchai, Wirote
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Konpang, Jessada
This study proposed a single-layer, compact, dual-port meta-surface multiple-input multiple-output (MIMO) antenna for Internet of Things (IoT) applications. Coupling between ports is effectively minimized using pin vias, which connects the meta-surface to the ground plane and functions as an LC resonator circuit to suppress useless frequencies. Here, L and C represent inductance and capacitance, respectively. Additionally, pin vias reduces mutual coupling by mitigating concentrated current distributions on the meta-surface components, achieving high isolation. The simulated results reveal a return loss bandwidth (RLBW) spanning 3.76-7.4 GHz (70% at a center frequency of 5.2 GHz) with isolation (S<inf>12</inf>) exceeding 19 dB. Furthermore, the envelope correlation coefficient is below 0.035, and the diversity gain reaches 9.82 dB. The antenna achieves a maximum gain of 5.54 dBi at 4.3 GHz. This demonstrates that the pin vias decoupling technique is highly effective for coupling reduction in meta-surface MIMO antennas.
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A low-complexity PAPR reduction for space-time block code MIMO-OFDM by using modified-PTS with ABC-concurrent algorithm
(2020-01-01)
Boontra, Pitchaya
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Mata, Tanairat
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Boonsrimuang, Pisit
One of the problems of using Orthogonal Frequency Division Multiplexing (OFDM) technique is the higher Peak-to-Average Power Ratio (PAPR) which leads to the fatal degradation of the system performance in the non-linear channel. To solve this problem, the partial transmit sequence (PTS) was proposed for Space-Time Block Code (STBC) with Multi-Input and Multi-Output (MIMO)-OFDM as STBC MIMO-OFDM system which can reduce the PAPR effectively. However, its complexity in the PAPR reduction process becomes higher in proportion to the increase of its considered cluster number. To solve this problem, this paper proposes a low-complexity PAPR reduction by using the modified-PTS with artificial bee colony (ABC) and concurrent algorithm as ABC-Concurrent algorithm for STBC MIMO-OFDM system which can improve better PAPR with low-complexity and can perform better Bit-Error-Rate (BER) in the non-linear channel. The silent features of the proposed modified-PTS with ABCConcurrent algorithm are to reduce the PAPR with decreasing side information (SI) to half by modifying PTS with the concurrent algorithm and to reduce the complexity in PAPR reduction process by applying ABC algorithm for STBC MIMO-OFDM system. From the various results by using computer simulation, it can be confirmed that the proposed modified-PTS with ABC-Concurrent algorithm can reduce PAPR by approximately 3.4 and 0.4 dB at CCDF 10<sup>-3</sup> as comparing with the original STBC MIMO-OFDM and conventional PTS methods respectively, and can use the complexity approximately only 19% in PAPR reduction process which is decreased a lot from using the conventional PTS method. Moreover, the proposed method can perform the better BER in the non-linear channel than the original STBC MIMO-OFDM and the conventional. PTS methods which is close to that of operating in nonlinear channel.
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Proposal of channel estimation scheme for practical V-BLAST MIMO-OFDM system
(2017-07-01)
Inkamchua, Nakarin
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Boonsrimuang, Pisit
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Mata, Tanairat
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Sopin, Anan
In wireless communication, multiple input and multiple output technique is often applied with orthogonal frequency division multiplexing (MIMO-OFDM) because of its many advantages such as spectral efficiency, link reliability, diversity gain and so on. In the practical MIMO-OFDM system, it has a signal aliasing problem due to the mismatch of sampling from adding zero padding at both front and rear of data transmission in each OFDM symbol. To solve this problem, the channel estimation by using the new comb-type pilot symbol arrangement scheme is proposed for the practical MIMO-OFDM system. From the computer results, it can be shown that the proposed channel estimation scheme can perform higher system performances than the conventional scheme in the practical V- BLAST MIMO-OFDM system.
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Proposal of time domain channel estimation method for MIMO-OFDM systems
(2015-01-01)
Mata, Tanairat
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Boonsrimuang, Pisit
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Mori, Kazuo
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Kobayashi, Hideo
This paper proposes a time domain channel estimation (TD-CE) method for Multi Input Multi Output-Orthogonal Frequency Division Multiplexing (MIMO-OFDM) systems. The feature of proposed TD-CE method is to estimate channel frequency responses for all links between transmit and receive antennas in MIMO-OFDM systems by using one scattered pilot preamble symbol in the time domain. The proposed method can achieve higher channel estimation accuracy even when the number of transmission antennas is larger and the transmission signal is sampled by a non-Nyquist rate in which the number of IFFT points is different from the number of data subcarriers due to the insertion of null subcarriers (zero padding) at the both ends of data subcarriers. This paper shows various computer simulation results in the time-varying fading channels to demonstrate the effectiveness of the proposed channel estimation method as comparing with the conventional channel estimation methods.
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Performance evaluation of error correction code in MIMO scheme for WBAN channel
(2014-01-27)
Sansoda, Buncha
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Choomchuay, Somsak
In most communications, the error correction code (ECC) is one good solution to maintaining the information accuracy between the transmitter and the receiver. Multiple-input-multiple-output (MIMO) technology is further adopted to increase the link quality and capacity for the same transmission power. This paper proposes the application of convolutional code (CC) combined with MIMO scheme to reduce the bit error probability in WBAN channel where binary Phase Shift Keying (BPSK) is assumed in channel modulation. The findings show that the combination scheme performs better than the conventional scheme particularly when the constraint length is increases.
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Proposal of STBC MIMO-OFDM for ITS systems
(2013-09-02)
Mata, Tanairat
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Naito, Katsuhiro
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Boonsrimuang, Pisit
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Mori, Kazuo
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Kobayashi, Hideo
Orthogonal Frequency Division Multiplexing (OFDM) is a popular technique in the wireless communication systems which can achieve high transmission data rate with high signal quality even in the multipath fading channel which is a typical operation condition under wireless communication systems. MIMO (Multi Input-Multi Output)-OFDM is also considered as a promising technique for realizing the future ITS services. In this paper, we propose a new road to vehicle communication system (RVC) for the ITS by using the STBC MIMO-OFDM technique which can achieve a high transmission data rate with high signal quality even under the high mobile ITS environments. © 2013 IEEE.
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Adaptive space-time receiver for cooperative relay networks
(2010-12-01)
Chaisong, R.
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Tekapakvisit, C.
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Benjangkaprasert, C.
In this paper, an adaptive space-time receiver for cooperative relay networks is proposed. Using cooperative amplify-and-forward relay nodes, it is possible to increasing the rank of the multiple-input multiple-output (MIMO) channel. The proposed receiver is based on a joint adaptive iterative detection and decoding algorithm, adaptively cancels co-channel interference and eliminates the multiple access interference. The least mean square (LMS) algorithm is used for the adaptive receiver. Simulation results show that the proposed scheme achieves better bit error rate (BER) performance compared with the traditional MIMO scheme. ©ICROS.

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