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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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A PAPR reduction scheme based on improved PTS with ABC algorithm for OFDM signal
(2018-07-02)
Mata, Tanairat
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Boonsrimuang, Pisit
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Boontra, Pitchaya
A high PAPR is well known as the serious problem of OFDM system because of a huge degradation of its signal quality, especially in the non-linear channel. From the reason, many PAPR reduction schemes have been proposed for solving this problem. The Partial Transmit Sequence (PTS) scheme is one of the PAPR reduction schemes which can improve the PAPR performance effectively. However, its computational complexity would be increased which is proportional to the increasing number of symbol clusters in the optimum PAPR value for a PAPR reduction process. To solve this problem, this paper proposes the PAPR reduction scheme based on the improved PTS with Artificial Bee Colony (ABC) algorithm for OFDM system. The potential capability of the proposed scheme is the PAPR reduction performance with low computational complexity which leads to the improvement of signal quality in the OFDM system. The excellent PAPR reduction performance with the low computational complexity of the proposed scheme has been verified by the computer simulations in this paper.
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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 channel estimation method for bi-directional OFDM based ANC in higher time-varying fading channel
(2014-01-01)
Mata, Tanairat
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Naito, Katsuhiro
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Mori, Kazuo
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Boonsrimuang, Pisit
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Kobayashi, Hideo
Broadband Analog Network Coding (ANC) based on OFDM has been widely investigated to increase capacity of bi-directional relay communications. The broadband ANC based on OFDM technique is required to estimate channel frequency responses (CFRs) between both user terminals (UTs) and a relay station (RS) precisely so as to remove the self-information data from the received signal and to demodulate the other user's information data with frequency equalization. Many channel estimation methods have been proposed for the OFDM based broadband ANC. However bit error rate (BER) performance of these methods would be degraded relatively in higher time- varying fading channels due to the inaccurate estimation of CFR. To solve this problem, this paper proposes a CFR estimation method which can achieve better BER performance with keeping higher transmission efficiency even in higher time-varying fading channels. The salient features of proposed CFR estimation method are to enable the estimation of combined CFR at the UT for both channels between the UTs and RS by using scattered pilot subcarriers and to enable the demodulation of information data without feedback information of CFR estimated at the RS. This paper presents various simulation results in the higher time-varying fading channels to demonstrate the effectiveness of proposed CFR estimation method for the bi-directional OFDM based ANC.
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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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Proposal of PAPR reduction method for OFDM signal by re-ordering of clusters
(2013-01-01)
Mata, Tanairat
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Naito, Katsuhiro
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Mori, Kazuo
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Kobayashi, Hideo
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Boonsrimuang, Pisit
One of the major disadvantages of OFDM technique is the high PAPR in the time domain signal. The larger PAPR signal would cause the fatal degradation of BER performance and un-desirable spectrum regrowth in the nonlinear channel. One of the promising PAPR reduction methods is the Partial Transmit Sequence (PTS) method which can achieve better PAPR performance with reasonable computation complexity. But the PTS method is required to inform the side information to the receiver for the correct demodulation of data information by using the separate channel. To solve the above problem, this paper proposes a new PAPR reduction method without requiring the separate channel. The salient feature of the proposed method is to reduce the PAPR performance by reordering of clusters in the frequency domain at the transmitter and reconstructing the clusters by using the cluster ID under embedded in the data information at the receiver. The proposed method can achieve almost the same PAPR performance and computation complexity as those for the PTS method without requiring the transmission of side information. This paper presents various computer simulation results to verify the effectiveness of the proposed method. © 2013 IEEE.
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Proposal of improved PTS method for STBC MIMO-OFDM systems
(2010-01-01)
Mata, Tanairat
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Boonsrimuang, Pornpawit
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Boonsrimuang, Pisit
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Kobayashi, Hideo
This paper proposes a new Partial Transmit Sequence (PTS) method in conjunction with the concurrent algorithm for Space Time Block Code Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing (STBC MIMO-OFDM) systems. The feature of proposed PTS method is that each cluster is divided into two parts and these two parts employ the different weighting factors to achieve the better Peak to Average Power Ratio (PAPR) with keeping the same size of side information and almost the same size of computational complexity as that for the conventional concurrent PTS method. Copyright © 2010 The Institute of Electronics, Information and Communication Engineers.
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A new weighting factor with concurrent PAPR reduction algorithm for STBC MIMO-OFDM
(2009-12-01)
Mata, Tanairat
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Boonsrimuang, Pornpawit
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Boonsrimuang, Pisit
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Kobayashi, Hideo
Partial Transmit Sequences (PTS) method seems to be attractive for the reduction of Peak to Average Power Ratio (PAPR) in the Orthogonal Frequency Division Multiplexing (OFDM) system, since it can obtain better PAPR property by modifying OFDM signals without any degradation of BER performance. Meanwhile it also shows the potential capability to be utilized in MIMO-OFDM system with a concurrent PAPR reduction algorithm based on the property of orthogonal Space-Time Block Coded (STBC)[1]. On the other hand, the PTS method can improve the PAPR reduction performance very well as increasing the number of weighting factors and clusters. However, the size of side information proportionally increases as increasing the number of weighting factors or/and clutters, which are required to the receiver for recovering the original data. In this paper, we propose a new determination method for the weighting factor of PTS in conjunction with the concurrent [2] algorithm for the STBC MIMO-OFDM systems, which can improve the PAPR performance, computation complexity without any increasing of side information, and improve the BER (Bit Error Rate) performance. ©2009 IEEE.

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