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Efficient reduction of peak-to-average power ratio in multiple-input multiple-output orthogonal frequency-division multiplexing system by shuffling cluster sequences
(2024-12-01)
Mi, Si Sar
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Mata, Tanairat
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Boonsrimuang, Pornpawit
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Boonsrimuang, Pisit
We propose a shuffling cluster sequence technique without separate side information (SI) for multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) systems. In the proposed technique, the active subcarriers over two consecutive OFDM symbols are divided into (Formula presented.) clusters, and each cluster (packet frame) includes a header for ID#cluster and payload for (Formula presented.). The (Formula presented.) clusters are shuffled to reduce the peak-to-average power ratio (PAPR) of the time-domain OFDM signal, which includes the information data and SI signals, with a low computational complexity. At the receiver, the information data can be correctly reconstructed by ID#cluster in the header of each cluster, achieving a smaller bit error rate than the conventional MIMO-OFDM system without PAPR reduction. Moreover, our technique is comparable with the conventional partial transmit sequence technique without the impact of a separate SI signal even when increasing the number of transmitter antennas in a nonlinear multipath fading channel.
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Performance Evaluation of the M-QAM Enhanced Subcarrier Index Modulation in the Multipath Fading Channel with the Non-Linear Amplifier
(2023-01-01)
Mi, Si Sar
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Siriwanitpong, Aphitchaya
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Boonsrimuang, Pornpawit
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Boonsrimuang, Pisit
One of the specifications of the next-generation mobile communication is to reduce the power consumption to transmit the signal. Enhanced subcarrier index modulation (eSIM-OFDM) is a novel multicarrier modulation scheme. However, the eSIM-OFDM scheme degraded a little frequency utilization than the conventional orthogonal frequency division multiplexing (C-OFDM) scheme at the higher M-QAM modulation techniques. It has a special feature to transmit the signal when compared with the C-OFDM scheme. Its special feature increased the power efficiency and improved the bit error rate (BER) performance than the C-OFDM scheme. In the literature, the BER performance of the eSIM-OFDM scheme is analyzed in the additive white Gaussian noise (AWGN) channel and compared BER performance of the C-OFDM scheme. But in the literature, the BER performance of the eSIM-OFDM scheme and C-OFDM scheme were not evaluated in the multipath fading channel. Because eSIM-OFDM includes a special feature called inactive and active subcarriers. In this paper, we will evaluate the BER performance of higher order modulated eSIM-OFDM signal in the multipath Rician fading channel by using the Zadoff-Chu sequence pilot in the non-linear mobile communication system and will compare the BER performance with the C-OFDM scheme. From the simulation results, we can see that the BER performance of the eSIM-OFDM scheme is much better than the C-OFDM scheme in the multipath Rician fading non-linear channel. In this paper, computer simulation will evaluate the BER performance of the higher order modulated eSIM-OFDM scheme in the multipath Rician fading non-linear channel.
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A Deep Learning-Based Channel Estimation for High-Speed Train Environments
(2022-01-01)
Siriwanitpong, Aphitchaya
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Boonsrimuang, Pornpawit
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Mori, Kazuo
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Boonsrimuang, Pisit
A communication system in the railway track environment provides constant channel coefficient property as trains travel on a predetermined route and speed. This channel characteristic provides advantages in designing a channel estimation. This paper proposes a channel estimation algorithm based on a deep learning network called the Convolutional Neural Network (CNN). The CNN has trained with an average Channel Frequency Response (CFR) dataset on railway track environments with different multi-path fading and noises. The CFR can be estimated using a known pilot symbol as conventional methods. The estimated CFR is also used to select the right CFR for multi-path fading compensation. The CNN will then classify the estimated CFR by recognizing estimated channel characteristics and determining the most matched estimated channel for equalization of received signals in a data channel. The simulation results show that the performance of the deep learning algorithms outperforms that of the conventional algorithms. Furthermore, the proposed method delivers better Bit Error Rate (BER) performance since the deep learning-based channel estimation can categorize the features of the channel characteristics with different multi-path and doppler shifts.
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Channel Estimation for Enhanced Subcarrier Index Modulation OFDM Using Zadoff-Chu Sequence Pilot in Nonlinear Channel
(2022-01-01)
Mi, Si Sar
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Siriwanitpong, Aphichaya
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Boonsrimuang, Pornpawit
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Boonsrimuang, Pisit
Orthogonal Frequency Division Multiplexing with Index Modulation (OFDM-IM) is a digital modulation scheme that conveys additional information bits by using the index of subcarriers. OFDM with enhanced subcarrier index modulation (OFDM-SIM) has been recently proposed to improve the bit error rate (BER) performance of multicarrier communication systems. It is challenging to estimate channel variation of the OFDM-SIM system in wireless communication systems for coherent detection at the receiver side. This paper proposes a new pilot data information Zadoff-Chu sequence for the channel estimation OFDM-SIM system. And OFDM-SIM channel estimation will be done by using the conventional OFDM-SIM symbol pilot and the proposed Zadoff-Chu sequence pilot in the multipath Rician fading channel. And evaluate the simulation results by using BER performance. BER results of channel estimation OFDM-SIM with proposed Zadoff-Chu sequence pilot decreased than BER results of channel estimation OFDM-SIM using conventional OFDM-SIM symbol pilot. And we evaluate the proposed Zadoff-Chu sequence channel estimation OFDM-SIM in a nonlinear multipath Rician fading channel. We can see that the proposed Zadoff-Chu sequence pilot outperformed than conventional OFDM-SIM symbol pilot in every input back off (IBO)=0 dB,-2dB,-4dB, and-6dB. Our proposed channel estimation method is evaluated by using computer simulation.
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Energy Efficiency Enhancement in 5G Heterogeneous Cellular Networks Using System Throughput Based Sleep Control Scheme
(2020-02-01)
Dataesatu, Arif
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Boonsrimuang, Pornpawit
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Mori, Kazuo
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Boonsrimuang, Pisit
Currently, Cellular architectures are designed with an efficient providing infrastructure is one of the critical challenges in 5G dense heterogeneous cellular networks (HetNets). By adding many small base stations (SBSs) in a macro base station (MBS) is one way to support the rapid growth of mobile data communication, high data rate services and to provide continuous coverage. The high number of network elements leads to a significant increase in power consumption. To solve the problem, the SBS on/off algorithm has been introduced to reduce power consumption but also reduced energy efficiency as we called the conventional schemes. This paper we proposed as the SBS switching to sleep state algorithm based on the system throughput (MBS cell throughput and SBS cell throughput) is used the decision criteria for SBS to be in the sleep state. The simulation results, The proposed scheme can reduce the total power consumption of the network and enhance energy efficiency more than the conventional schemes.
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Comparative analysis of radio propagation models for LTE network on the sky train
(2019-04-29)
Dataesatu, Arif
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Boonsrimuang, Pornpawit
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Mori, Kazuo
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Boonsrimuang, Pisit
The usage of smartphones and computer for the data communications have become a more integrated part of everyday life for a large majority of the population. One important mode of transportation is the sky train, and users increasingly expect to be able to communicate satisfyingly while traveling on the train: MRT (Mass Rapid Transit Authority of Thailand). However, the radio conditions inside a train are very complex. A possibly large number of users that use at the same time, moving at high speed and a special environment on elevated guideways (height 20 m) are created big challenges for the data communication in LTE network. The accuracy of the path loss model is a very important tool to design the coverage areas and improve the performance in LTE network. This paper that studies and improve the accuracy of the path loss model, which use to design the coverage area of the LTE network under the sky train environment. Normally the radio propagation models under the urban area are designed on the ground approximately 1-3 meters in height but are not suitable for the user in the sky train, which is 20 meters high. we propose the Ericsson urban model in the special environment as sky train by the new values for a0 from 36.2 to 47.2 and a1 from 30.2 to 14.2. The proposed new coefficient for Ericsson urban model shows the most accurate path loss under the sky train with the urban area. The filed measurement is used by the smartphone-based measurement for low cost and practical usage.
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Proposal of sub-optimum algorithm for trellis-based SLM reducing PAPR of FBMC-OQAM signals
(2018-05-30)
Rujiprechanon, Latthawit
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Boonsrimuang, Pisit
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Sanpan, Sunisa
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Boonsrimuang, Pornpawit
Filter bank multi-carrier with offset quadrature amplitude modulation (FBMC-OQAM) has several advantages. FBMC-OQAM is considered a major candidate for the next generation mobile communication systems. The high peak-to-average power ratio (PAPR) is one of disadvantage for FBMC-OQAM signal which could be solved by the Trellis-based SLM (TSLM) technique. This TSLM technique has a much better PAPR reduction performance. However, the trellis-based algorithm has high computational complexity. This paper proposes the sub-optimum algorithm for trellis-based SLM scheme. The proposed algorithm show much lower computational complexity than trellis-based SLM scheme with small degradation of PAPR reduction performance. On the other hand, the PAPR reduction performance of proposed algorithm shows better than conventional SLM with similar computational complexity when the number of L symbols is large. The efficiencies of proposed scheme were verified by using various computer simulations.
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PAPR reduction in FBMC-OQAM signals with half complexity of trellis-based SLM
(2018-03-23)
Jirajaracheep, Panya
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Sanpan, Sunisa
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Boonsrimuang, Pornpawit
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Boonsrimuang, Pisit
The filter Bank Multicarrier (FBMC) modulation with offset-QAM (OQAM) has attracted attention as a major candidate for future wireless communication systems which has several advantages. A disadvantage of FBMC-OQAM is high peak-to-average power ratio (PAPR). To overcome this problem, the trellis-based SLM technique is employed and achieved a much better PAPR reduction performance. However, The Trellis-based algorithm has also the intrinsic disadvantage of high computational complexity, to decreasing the complexity will make the system more desirable. This paper proposes the half-complexity algorithm for trellis-based SLM scheme which achieves lower computational complexity when compared to trellis-based SLM scheme with small degradation of PAPR reduction performance. From various simulation results, the proposed algorithm shows less computational complexity about 50% compared to the trellis-based algorithm with similar PAPR reduction performance.
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Improved PTS method with new weighting factor technique for FBMC-OQAM systems
(2017-03-29)
Hanprasitkum, Amnart
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Numsomran, Arjin
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Boonsrimuang, Pornpawit
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Boonsrimuang, Pisit
Filter bank multi-carrier (FBMC) with offset quadrature amplitude modulation (OQAM) has been regarded as one of the candidates for next generation broadband wireless communication systems. Similar to OFDM systems, one of the major drawbacks in FBMC-OQAM systems is high peak-to-average power ratio (PAPR). To overcome this problem, Partial Transmit Sequence (PTS) method is a well - known method which can reduce the peak-to-average ratio (PAPR) for a multicarrier modulation signal. The PTS method can improve PAPR reduction performance very well as increasing the number of predetermined discrete phase factors and number of clusters. However, the side information is proportioned increasing as increased number of predetermined discrete phase factors or/and clutters that it is required to inform to the receiver for recovering the original data. In this paper, we propose the new discrete phase factor pattern which can improved the PAPR reduction performance better than conventional PTS method. This paper presents various computer simulation results to verify the effectiveness of proposed method.
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A low-complexity PS based radix IFFT method for PAPR reduction in OFDM systems
(2014-01-01)
Reangsuntea, Arttapol
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Boonsrimuang, Pornpawit
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Reangsuntea, Pongsathorn
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Boonsrimuang, Pisit
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Kobayashi, Hideo
We have proposed one of the distortion-less PAPR reduction methods which employs the Permutation Sequence (PS) in the frequency domain with embedded side information. However, the proposed PS method has high computation complexity. To improve the computation complexity for the previous proposed PS method, this paper proposes a low-complexity PS method which can keep the better peak-to-average power ratio (PAPR). In the proposed PS method, the signals at the middle stages of an N-point radix IFFT using decimation in frequency (DIF) is considered for PS processing. This paper shows that the proposed method has a lower multiplicative complexity than conventional PS method with keeping the PAPR reduction performance. The proposed method is called PS based radix IFFT, where DIF-IFFT is assigned through different stages of the IFFT transform. This proposed method can reduce the multiplicative complexity relatively with keeping the similar PAPR reduction to other methods such as C-PTS and C-PS. The proposed method also can reduce the side information as compared with the C-PTS. This paper presents the various computer simulation results to verify the effectiveness of proposed method. © 2014 Global IT Research Institute (GIRI).

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