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Muhammad Imran - One of the best experts on this subject based on the ideXlab platform.

  • Interference Analysis of QAM based Filter Bank Multicarrier System with Index Modulation
    arXiv: Signal Processing, 2018
    Co-Authors: Adnan Zafar, Pei Xiao, Lei Zhang, Aijun Cao, Mahmoud Abdullahi, Muhammad Imran
    Abstract:

    Index modulation (IM) has recently emerged as a promising concept for spectrum and energy-efficient next generation wireless communications Systems since it strikes a good balance among error performance, complexity, and spectral efficiency. IM technique, when applied to Multicarrier waveforms, yields the ability to convey the information not only by M-ary signal constellations as in conventional Multicarrier Systems but also by the indexes of the subcarriers, which are activated according to the incoming bit stream. Although IM is well studied for OFDM based Systems, FBMC with index modulation has not been thoroughly investigated. In this paper, we shed light on the potential and implementation of IM technique for QAM based FBMC System. We start with a mathematical model of the IM based QAM-FBMC System (FBMC/QAM-IM) along with the derivation of interference terms at the receiver due to channel distortions and noise. The interference terms including the ones introduced by the multipath channel are analyzed in terms of MSE and output SINR. It is shown with analytical and simulation results that the interference power in FBMC/QAM-IM is smaller compared to that of the conventional FBMC/QAM System as some of the subcarriers are inactive. The performance of FBMC/QAM with IM is investigated by comparing the SIR and output SINR with that of the conventional FBMC/QAM System along with the BER performance which shows that the FBMC/QAM-IM is a promising transmission technique for future wireless networks.

  • Performance Analysis and Optimization ofDCT-Based Multicarrier System onFrequency-Selective Fading Channels
    2018
    Co-Authors: Lei Zhang, Pei Xiao, Aijun Cao, Juquan Mao, Muhammad Imran
    Abstract:

    Regarded as one of the most promising transmission techniques for future wireless communications, the discrete cosine transform (DCT) based Multicarrier modulation (MCM) System employs cosine basis as orthogonal functions for real-modulated symbols multiplexing, by which the minimum orthogonal frequency spacing can be reduced by half compared to discrete Fourier transform (DFT) based one. With a time-reversed prefilter employed at the front of the receiver, interference-free one-tap equalization is achievable for the DCT-based Systems. However, due to the correlated pre-filtering operation in time domain, the signal-to-noise ratio (SNR) is enhanced as a result at the output. This leads to reformulated detection criterion to compensate for such filtering effect, rendering minimum-meansquare- error (MMSE) and maximum likelihood (ML) detections applicable to the DCT-based Multicarrier System. In this paper, following on the pre-filtering based DCT-MCM model that build in the literature work, we extend the overall System by considering both transceiver perfections and imperfections, where frequency offset, time offset and insufficient guard sequence are included. In the presence of those imperfection errors, the DCTMCM Systems are analysed in terms of desired signal power, inter-carrier interference (ICI) and inter-symbol interference (ISI). Thereafter, new detection algorithms based on zero forcing (ZF) iterative results are proposed to mitigate the imperfection effect. Numerical results show that the theoretical analysis match the simulation results, and the proposed iterative detection algorithms are able to improve the overall System performance significantly.

  • Complex-Valued Symbol Transmissions in Filter Bank Multicarrier Systems using Filter Deconvolution
    arXiv: Signal Processing, 2017
    Co-Authors: Adnan Zafar, Pei Xiao, Lei Zhang, Mahmoud Abdullahi, Sohail Taheri, Muhammad Imran
    Abstract:

    Transmission of complex-valued symbols using filter bank Multicarrier Systems has been an issue due to the self-interference between the transmitted symbols both in the time and frequency domain (so-called intrinsic interference). In this paper, we propose a novel low-complexity interference-free filter bank Multicarrier System with QAM modulation (FBMC/QAM) using filter deconvolution. The proposed method is based on inversion of the prototype filters which completely removes the intrinsic interference at the receiver and allows the use of complex-valued signaling. The interference terms in FBMC/QAM with and without the proposed System are analyzed and compared in terms of mean square error (MSE). It is shown with theoretical and simulation results that the proposed method cancels the intrinsic interference and improves the output signal to interference plus noise ratio (SINR) at the expense of slight enhancement of residual interferences caused by multipath channel. The complexity of the proposed System is also analyzed along with performance evaluation in an asynchronous multiservice scenario. It is shown that the proposed FBMC/QAM System with filter deconvolution outperforms the conventional OFDM System.

  • ISWCS - Output SNR analysis and detection criteria for optimum DCT-based Multicarrier System
    2016 International Symposium on Wireless Communication Systems (ISWCS), 2016
    Co-Authors: Lei Zhang, Pei Xiao, Aijun Cao, Juquan Mao, Muhammad Imran
    Abstract:

    The discrete cosine transform (DCT) based Multicarrier System is regarded as one of the complementary Multicarrier transmission techniques for 5th Generation (5G) applications in near future. By employing cosine basis as orthogonal functions for multiplexing each real-valued symbol with symbol period of T , it is able to reduce the minimum orthogonal frequency spacing to 1/(2T ) Hz, which is only half of that compared to discrete Fourier transform (DFT) based Multicarrier Systems. Critical to the optimal DCT-based System design that achieves interference-free single-tap equalization, not only both prefix and suffix are needed as symmetric extension of information block, but also a so-called front-end pre-filter is necessarily introduced at the receiver side. Since the pre-filtering process is essentially a time reversed convolution for continuous inputs, the output signal-to-noise ratio (SNR) for each subcarrier after filtering is enhanced. In this paper, the impact of pre-filtering on the System performance is analyzed in terms of ergodic output SNR per subcarrier. This is followed by reformulated detection criterion where such filtering process is taken into consideration. Numerical results show that under modified detection criteria, the proposed detection algorithms improve the overall bit error rate (BER) performance effectively

Pei Xiao - One of the best experts on this subject based on the ideXlab platform.

  • Interference Analysis of QAM based Filter Bank Multicarrier System with Index Modulation
    arXiv: Signal Processing, 2018
    Co-Authors: Adnan Zafar, Pei Xiao, Lei Zhang, Aijun Cao, Mahmoud Abdullahi, Muhammad Imran
    Abstract:

    Index modulation (IM) has recently emerged as a promising concept for spectrum and energy-efficient next generation wireless communications Systems since it strikes a good balance among error performance, complexity, and spectral efficiency. IM technique, when applied to Multicarrier waveforms, yields the ability to convey the information not only by M-ary signal constellations as in conventional Multicarrier Systems but also by the indexes of the subcarriers, which are activated according to the incoming bit stream. Although IM is well studied for OFDM based Systems, FBMC with index modulation has not been thoroughly investigated. In this paper, we shed light on the potential and implementation of IM technique for QAM based FBMC System. We start with a mathematical model of the IM based QAM-FBMC System (FBMC/QAM-IM) along with the derivation of interference terms at the receiver due to channel distortions and noise. The interference terms including the ones introduced by the multipath channel are analyzed in terms of MSE and output SINR. It is shown with analytical and simulation results that the interference power in FBMC/QAM-IM is smaller compared to that of the conventional FBMC/QAM System as some of the subcarriers are inactive. The performance of FBMC/QAM with IM is investigated by comparing the SIR and output SINR with that of the conventional FBMC/QAM System along with the BER performance which shows that the FBMC/QAM-IM is a promising transmission technique for future wireless networks.

  • Performance Analysis and Optimization ofDCT-Based Multicarrier System onFrequency-Selective Fading Channels
    2018
    Co-Authors: Lei Zhang, Pei Xiao, Aijun Cao, Juquan Mao, Muhammad Imran
    Abstract:

    Regarded as one of the most promising transmission techniques for future wireless communications, the discrete cosine transform (DCT) based Multicarrier modulation (MCM) System employs cosine basis as orthogonal functions for real-modulated symbols multiplexing, by which the minimum orthogonal frequency spacing can be reduced by half compared to discrete Fourier transform (DFT) based one. With a time-reversed prefilter employed at the front of the receiver, interference-free one-tap equalization is achievable for the DCT-based Systems. However, due to the correlated pre-filtering operation in time domain, the signal-to-noise ratio (SNR) is enhanced as a result at the output. This leads to reformulated detection criterion to compensate for such filtering effect, rendering minimum-meansquare- error (MMSE) and maximum likelihood (ML) detections applicable to the DCT-based Multicarrier System. In this paper, following on the pre-filtering based DCT-MCM model that build in the literature work, we extend the overall System by considering both transceiver perfections and imperfections, where frequency offset, time offset and insufficient guard sequence are included. In the presence of those imperfection errors, the DCTMCM Systems are analysed in terms of desired signal power, inter-carrier interference (ICI) and inter-symbol interference (ISI). Thereafter, new detection algorithms based on zero forcing (ZF) iterative results are proposed to mitigate the imperfection effect. Numerical results show that the theoretical analysis match the simulation results, and the proposed iterative detection algorithms are able to improve the overall System performance significantly.

  • SPAWC - Rate-Splitting for Multigroup Multicast Beamforming in Multicarrier Systems
    2018 IEEE 19th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), 2018
    Co-Authors: Hongzhi Chen, Pei Xiao, Zheng Chu, Rahim Tafazolli
    Abstract:

    In this paper, we consider multigroup multicast transmissions with different types of service messages in an overloaded Multicarrier System, where the number of transmitter antennas is insufficient to mitigate all inter-group interference. We show that employing a rate-splitting based multiuser beamforming approach enables a simultaneous delivery of the multiple service messages over the same time-frequency resources in a non-orthogonal fashion. Such an approach, taking into account transmission power constraints which are inevitable in practice, outperforms classic beamforming methods as well as current standardized multicast technologies, in terms of both spectrum efficiency and the flexibility of radio resource allocation.

  • Complex-Valued Symbol Transmissions in Filter Bank Multicarrier Systems using Filter Deconvolution
    arXiv: Signal Processing, 2017
    Co-Authors: Adnan Zafar, Pei Xiao, Lei Zhang, Mahmoud Abdullahi, Sohail Taheri, Muhammad Imran
    Abstract:

    Transmission of complex-valued symbols using filter bank Multicarrier Systems has been an issue due to the self-interference between the transmitted symbols both in the time and frequency domain (so-called intrinsic interference). In this paper, we propose a novel low-complexity interference-free filter bank Multicarrier System with QAM modulation (FBMC/QAM) using filter deconvolution. The proposed method is based on inversion of the prototype filters which completely removes the intrinsic interference at the receiver and allows the use of complex-valued signaling. The interference terms in FBMC/QAM with and without the proposed System are analyzed and compared in terms of mean square error (MSE). It is shown with theoretical and simulation results that the proposed method cancels the intrinsic interference and improves the output signal to interference plus noise ratio (SINR) at the expense of slight enhancement of residual interferences caused by multipath channel. The complexity of the proposed System is also analyzed along with performance evaluation in an asynchronous multiservice scenario. It is shown that the proposed FBMC/QAM System with filter deconvolution outperforms the conventional OFDM System.

  • Cyclic Prefix-Based Universal Filtered Multicarrier System and Performance Analysis
    IEEE Signal Processing Letters, 2016
    Co-Authors: Lei Zhang, Pei Xiao, Atta Quddus
    Abstract:

    Recently proposed universal filtered Multicarrier (UFMC) System is not an orthogonal System in multipath channel environments and might cause significant performance loss. In this paper, the authors propose a cyclic prefix (CP) based UFMC System and first analyze the conditions for interference-free one-tap equalization in the absence of transceiver imperfections. Then the corresponding signal model and output signal-to-noise ratio expression are derived. In the presence of carrier frequency offset, timing offset, and insufficient CP length, the authors establish an analytical System model as a summation of desired signal, intersymbol interference, intercarrier interference, and noise. New channel equalization algorithms are proposed based on the derived analytical signal model. Numerical results show that the derived model matches the simulation results precisely, and the proposed equalization algorithms improve the UFMC System performance in terms of bit error rate.

Lei Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Interference Analysis of QAM based Filter Bank Multicarrier System with Index Modulation
    arXiv: Signal Processing, 2018
    Co-Authors: Adnan Zafar, Pei Xiao, Lei Zhang, Aijun Cao, Mahmoud Abdullahi, Muhammad Imran
    Abstract:

    Index modulation (IM) has recently emerged as a promising concept for spectrum and energy-efficient next generation wireless communications Systems since it strikes a good balance among error performance, complexity, and spectral efficiency. IM technique, when applied to Multicarrier waveforms, yields the ability to convey the information not only by M-ary signal constellations as in conventional Multicarrier Systems but also by the indexes of the subcarriers, which are activated according to the incoming bit stream. Although IM is well studied for OFDM based Systems, FBMC with index modulation has not been thoroughly investigated. In this paper, we shed light on the potential and implementation of IM technique for QAM based FBMC System. We start with a mathematical model of the IM based QAM-FBMC System (FBMC/QAM-IM) along with the derivation of interference terms at the receiver due to channel distortions and noise. The interference terms including the ones introduced by the multipath channel are analyzed in terms of MSE and output SINR. It is shown with analytical and simulation results that the interference power in FBMC/QAM-IM is smaller compared to that of the conventional FBMC/QAM System as some of the subcarriers are inactive. The performance of FBMC/QAM with IM is investigated by comparing the SIR and output SINR with that of the conventional FBMC/QAM System along with the BER performance which shows that the FBMC/QAM-IM is a promising transmission technique for future wireless networks.

  • Performance Analysis and Optimization ofDCT-Based Multicarrier System onFrequency-Selective Fading Channels
    2018
    Co-Authors: Lei Zhang, Pei Xiao, Aijun Cao, Juquan Mao, Muhammad Imran
    Abstract:

    Regarded as one of the most promising transmission techniques for future wireless communications, the discrete cosine transform (DCT) based Multicarrier modulation (MCM) System employs cosine basis as orthogonal functions for real-modulated symbols multiplexing, by which the minimum orthogonal frequency spacing can be reduced by half compared to discrete Fourier transform (DFT) based one. With a time-reversed prefilter employed at the front of the receiver, interference-free one-tap equalization is achievable for the DCT-based Systems. However, due to the correlated pre-filtering operation in time domain, the signal-to-noise ratio (SNR) is enhanced as a result at the output. This leads to reformulated detection criterion to compensate for such filtering effect, rendering minimum-meansquare- error (MMSE) and maximum likelihood (ML) detections applicable to the DCT-based Multicarrier System. In this paper, following on the pre-filtering based DCT-MCM model that build in the literature work, we extend the overall System by considering both transceiver perfections and imperfections, where frequency offset, time offset and insufficient guard sequence are included. In the presence of those imperfection errors, the DCTMCM Systems are analysed in terms of desired signal power, inter-carrier interference (ICI) and inter-symbol interference (ISI). Thereafter, new detection algorithms based on zero forcing (ZF) iterative results are proposed to mitigate the imperfection effect. Numerical results show that the theoretical analysis match the simulation results, and the proposed iterative detection algorithms are able to improve the overall System performance significantly.

  • Complex-Valued Symbol Transmissions in Filter Bank Multicarrier Systems using Filter Deconvolution
    arXiv: Signal Processing, 2017
    Co-Authors: Adnan Zafar, Pei Xiao, Lei Zhang, Mahmoud Abdullahi, Sohail Taheri, Muhammad Imran
    Abstract:

    Transmission of complex-valued symbols using filter bank Multicarrier Systems has been an issue due to the self-interference between the transmitted symbols both in the time and frequency domain (so-called intrinsic interference). In this paper, we propose a novel low-complexity interference-free filter bank Multicarrier System with QAM modulation (FBMC/QAM) using filter deconvolution. The proposed method is based on inversion of the prototype filters which completely removes the intrinsic interference at the receiver and allows the use of complex-valued signaling. The interference terms in FBMC/QAM with and without the proposed System are analyzed and compared in terms of mean square error (MSE). It is shown with theoretical and simulation results that the proposed method cancels the intrinsic interference and improves the output signal to interference plus noise ratio (SINR) at the expense of slight enhancement of residual interferences caused by multipath channel. The complexity of the proposed System is also analyzed along with performance evaluation in an asynchronous multiservice scenario. It is shown that the proposed FBMC/QAM System with filter deconvolution outperforms the conventional OFDM System.

  • Cyclic Prefix-Based Universal Filtered Multicarrier System and Performance Analysis
    IEEE Signal Processing Letters, 2016
    Co-Authors: Lei Zhang, Pei Xiao, Atta Quddus
    Abstract:

    Recently proposed universal filtered Multicarrier (UFMC) System is not an orthogonal System in multipath channel environments and might cause significant performance loss. In this paper, the authors propose a cyclic prefix (CP) based UFMC System and first analyze the conditions for interference-free one-tap equalization in the absence of transceiver imperfections. Then the corresponding signal model and output signal-to-noise ratio expression are derived. In the presence of carrier frequency offset, timing offset, and insufficient CP length, the authors establish an analytical System model as a summation of desired signal, intersymbol interference, intercarrier interference, and noise. New channel equalization algorithms are proposed based on the derived analytical signal model. Numerical results show that the derived model matches the simulation results precisely, and the proposed equalization algorithms improve the UFMC System performance in terms of bit error rate.

  • ISWCS - Output SNR analysis and detection criteria for optimum DCT-based Multicarrier System
    2016 International Symposium on Wireless Communication Systems (ISWCS), 2016
    Co-Authors: Lei Zhang, Pei Xiao, Aijun Cao, Juquan Mao, Muhammad Imran
    Abstract:

    The discrete cosine transform (DCT) based Multicarrier System is regarded as one of the complementary Multicarrier transmission techniques for 5th Generation (5G) applications in near future. By employing cosine basis as orthogonal functions for multiplexing each real-valued symbol with symbol period of T , it is able to reduce the minimum orthogonal frequency spacing to 1/(2T ) Hz, which is only half of that compared to discrete Fourier transform (DFT) based Multicarrier Systems. Critical to the optimal DCT-based System design that achieves interference-free single-tap equalization, not only both prefix and suffix are needed as symmetric extension of information block, but also a so-called front-end pre-filter is necessarily introduced at the receiver side. Since the pre-filtering process is essentially a time reversed convolution for continuous inputs, the output signal-to-noise ratio (SNR) for each subcarrier after filtering is enhanced. In this paper, the impact of pre-filtering on the System performance is analyzed in terms of ergodic output SNR per subcarrier. This is followed by reformulated detection criterion where such filtering process is taken into consideration. Numerical results show that under modified detection criteria, the proposed detection algorithms improve the overall bit error rate (BER) performance effectively

Adnan Zafar - One of the best experts on this subject based on the ideXlab platform.

  • Interference Analysis of QAM based Filter Bank Multicarrier System with Index Modulation
    arXiv: Signal Processing, 2018
    Co-Authors: Adnan Zafar, Pei Xiao, Lei Zhang, Aijun Cao, Mahmoud Abdullahi, Muhammad Imran
    Abstract:

    Index modulation (IM) has recently emerged as a promising concept for spectrum and energy-efficient next generation wireless communications Systems since it strikes a good balance among error performance, complexity, and spectral efficiency. IM technique, when applied to Multicarrier waveforms, yields the ability to convey the information not only by M-ary signal constellations as in conventional Multicarrier Systems but also by the indexes of the subcarriers, which are activated according to the incoming bit stream. Although IM is well studied for OFDM based Systems, FBMC with index modulation has not been thoroughly investigated. In this paper, we shed light on the potential and implementation of IM technique for QAM based FBMC System. We start with a mathematical model of the IM based QAM-FBMC System (FBMC/QAM-IM) along with the derivation of interference terms at the receiver due to channel distortions and noise. The interference terms including the ones introduced by the multipath channel are analyzed in terms of MSE and output SINR. It is shown with analytical and simulation results that the interference power in FBMC/QAM-IM is smaller compared to that of the conventional FBMC/QAM System as some of the subcarriers are inactive. The performance of FBMC/QAM with IM is investigated by comparing the SIR and output SINR with that of the conventional FBMC/QAM System along with the BER performance which shows that the FBMC/QAM-IM is a promising transmission technique for future wireless networks.

  • Complex-Valued Symbol Transmissions in Filter Bank Multicarrier Systems using Filter Deconvolution
    arXiv: Signal Processing, 2017
    Co-Authors: Adnan Zafar, Pei Xiao, Lei Zhang, Mahmoud Abdullahi, Sohail Taheri, Muhammad Imran
    Abstract:

    Transmission of complex-valued symbols using filter bank Multicarrier Systems has been an issue due to the self-interference between the transmitted symbols both in the time and frequency domain (so-called intrinsic interference). In this paper, we propose a novel low-complexity interference-free filter bank Multicarrier System with QAM modulation (FBMC/QAM) using filter deconvolution. The proposed method is based on inversion of the prototype filters which completely removes the intrinsic interference at the receiver and allows the use of complex-valued signaling. The interference terms in FBMC/QAM with and without the proposed System are analyzed and compared in terms of mean square error (MSE). It is shown with theoretical and simulation results that the proposed method cancels the intrinsic interference and improves the output signal to interference plus noise ratio (SINR) at the expense of slight enhancement of residual interferences caused by multipath channel. The complexity of the proposed System is also analyzed along with performance evaluation in an asynchronous multiservice scenario. It is shown that the proposed FBMC/QAM System with filter deconvolution outperforms the conventional OFDM System.

Daesik Hong - One of the best experts on this subject based on the ideXlab platform.

  • a new filter bank Multicarrier System with two prototype filters for qam symbols transmission and reception
    IEEE Transactions on Wireless Communications, 2016
    Co-Authors: Hyungju Nam, Moonchang Choi, Chanhong Kim, Sooyong Choi, Seongbae Han, Daesik Hong
    Abstract:

    A filter-bank Multicarrier–quadrature amplitude modulation (FBMC-QAM) System with two prototype filters for transmitting QAM symbol is proposed, and the orthogonality conditions for the FBMC-QAM System without the intrinsic interference is derived. The proposed transmitter performs the individual filtering for the even and odd-numbered sub-carrier symbols, respectively. In order to satisfy the derived orthogonality conditions, we perform a sub-block wise reverse ordering procedure for the outputs of the odd-numbered sub-carrier filter. Also, this paper shows that the proposed FBMC-QAM System satisfies the suggested orthogonality conditions and can use the multiple-input multiple-output transmission schemes as the conventional orthogonal frequency division multiplexing (OFDM) Systems. The signal-to-interference power ratio and the bit error rate (BER) for the proposed FBMC-QAM System are evaluated. Numerical results show that the proposed FBMC-QAM System has almost the same BER performance compared with the FBMC-OQAM and OFDM Systems.

  • a new filter bank Multicarrier System for qam signal transmission and reception
    International Conference on Communications, 2014
    Co-Authors: Hyungju Nam, Moonchang Choi, Chanhong Kim, Daesik Hong, Sooyong Choi
    Abstract:

    A filter-bank Multicarrier - quadrature amplitude modulation (FBMC-QAM) System with two prototype filters for transmitting QAM signal is proposed. The proposed transmitter performs separate filtering for the even-numbered sub-carrier symbols and the odd-numbered sub-carrier symbols. We derive the orthogonality conditions for a FBMC-QAM System without the intrinsic interference. In order to satisfy the suggested orthogonality conditions, we perform a kind of block interleaving for the odd-numbered sub-carrier filtering. The receiver structure is the counterpart to the transmitter. Numerical results showed that the proposed FBMC-QAM System has almost the same bit error rate (BER) performance compared to the FBMC-OQAM and the orthogonal frequency division multiplexing (OFDM) System. with the proposed FBMC-QAM, multiple-input multiple-output transmission schemes and channel estimation schemes can be utilized similarly as in OFDM.