Frequency domain equalization for single-carrier broadband wireless systems
TL;DR: This article surveys frequency domain equalization (FDE) applied to single-carrier (SC) modulation solutions and discusses similarities and differences of SC and OFDM systems and coexistence possibilities, and presents examples of SC-FDE performance capabilities.
Abstract: Broadband wireless access systems deployed in residential and business environments are likely to face hostile radio propagation environments, with multipath delay spread extending over tens or hundreds of bit intervals. Orthogonal frequency-division multiplex (OFDM) is a recognized multicarrier solution to combat the effects of such multipath conditions. This article surveys frequency domain equalization (FDE) applied to single-carrier (SC) modulation solutions. SC radio modems with frequency domain equalization have similar performance, efficiency, and low signal processing complexity advantages as OFDM, and in addition are less sensitive than OFDM to RF impairments such as power amplifier nonlinearities. We discuss similarities and differences of SC and OFDM systems and coexistence possibilities, and present examples of SC-FDE performance capabilities.
Citations
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01 Aug 2019
TL;DR: The interference coordination techniques, i.e., the user clustering and the decentralized inter-cell (or inter-BS) interference coordination, for further improving the area spectrum efficiency and for enhancing the flexible and scalable deployment of distributed MIMO system are presented.
Abstract: This paper presents a comprehensive introduction of the distributed MIMO cooperative transmission technique which has been developed under the framework of national 5G research & development (4-year project of 2015 2018) funded by Ministry of Internal Affairs and Communications (MIC), Japan. The distributed MIMO cooperative transmission includes single-user space-time block code transmit diversity (STBC-TD), multi-user minimum mean square error (MMSE) based filtering jointly used with eigenmode filtering obtained by singular value decomposition (SVD), called MMSE-SVD in short, and blind selected mapping (blind SLM). The bit error rate (BER), link capacity, and peak-to-average power ratio (PAPR)-complexity tradeoff performances of distributed MIMO cooperative transmission, evaluated by extensive numerical and computer simulation, are presented. Furthermore, the interference coordination techniques, i.e., the user clustering and the decentralized inter-cell (or inter-BS) interference coordination (ICIC), for further improving the area spectrum efficiency and for enhancing the flexible and scalable deployment of distributed MIMO system are also presented.
3Â citations
Cites methods from "Frequency domain equalization for s..."
...For OFDM downlink transmission, STBC coding and maximal ratio transmit FDE (MRT-FDE) are applied to generate an NbsĂ—2 transmit symbol matrix....
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...This leads to CSI sharing between BS and UE and implementing FDE at BS transceiver for both uplink reception and downlink transmission....
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...A powerful equalization technique such as frequency-domain equalization (FDE) [8-10] is indispensable to 2019 IEEE/CIC International Conference on Communications in China (ICCC)...
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...Then, minimum mean-square error based FDE (MMSE-FDE) is applied before STBC decoding at BS....
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...A powerful equalization technique such as frequency-domain equalization (FDE) [8-10] is indispensable to deal with this problem....
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TL;DR: In this article , the authors considered a downlink discrete cosine transform (DCT) based NOMA-OFDM system with equalization and interference compensation jointly in the fractional Fourier domain (FFD).
3Â citations
Patent•
01 Oct 2008
TL;DR: In this paper, a signal generator and signal processor for single carrier wireless communication systems with frequency domain equalizer, which are operable to use pseudorandom-noise sequences for cyclic prefix.
Abstract: The present invention relates to a signal generator and signal processor for single carrier wireless communication systems with frequency domain equalizer, which are operable to use pseudorandom-noise sequences for cyclic prefix. The different arrangements and examples of said pseudorandom-noise sequences could be used for coarse timing synchronization, channel estimation, carrier synchronization, signal-noise-ration estimation and channel equalization.
3Â citations
Journal Article•
01 Jan 2017-International journal of advanced research in electrical, electronics and instrumentation engineering
TL;DR: Simulation results have proved that the BER performance is not much affected by the PAPR reduction, and the effect of peak power reduction and the channel estimation error on the system Bit Error Rate is investigated.
Abstract: The Single-Carrier Frequency Division Multiple Access (SC-FDMA) system is a popular system in mobile communication systems because of its advantage of low Peak-to-Average-Power- Ratio (PAPR), and the use of frequency-domain equalizers techniques to reduce Inter-Symbol Interference (ISI) and Inter-Carrier Interference (ICI). This paper presents a comprehensive study of the SC-FDMA system with PAPR reduction using clipping and filtering in the presence of channel estimation errors for two different versions of SC-FDMA adopting the FFT and the DCT. The effect of peak power reduction and the channel estimation error on the system Bit Error Rate (BER) is investigated. Simulation results have proved that the BER performance is not much affected by the PAPR reduction.
3Â citations
01 May 2006
TL;DR: Front-end imperfections are examined to demonstrate the influence of erroneous calibration, phase noise and nonlinear amplifiers, which increases with the number of spatially multiplexed data streams culminating in unacceptable performance degradation in fully loaded systems.
Abstract: In multiuser multiple-input multiple-output (MIMO) systems the performance of joint detection and joint predistortion techniques highly depends on the quality of radio-frequency (RF) components. Therefore, the focus of this paper is on front-end imperfections. We demonstrate the influence of erroneous calibration (which is essential for downlink predistortion), phase noise and nonlinear amplifiers. For all issues we elaborate on the different disturbances that arise, analyse the impact on symbol estimation and evaluate system performance in ierms of coded bit error ratio (BER). A general result for all examined front-end imperfections is that their influence increases with the number of spatially multiplexed data streams culminating in unacceptable performance degradation in fully loaded systems. Moreover, Wiener-based detection and predistortion reduces the degradation due to front-end imperfections in low SNR regimes compared to zero forcing.
3Â citations
Cites background from "Frequency domain equalization for s..."
...However, for very low offset frequencies, the TCXO phase noise might dominate with a 1=f 2 slope [15]....
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References
More filters
Book•
01 Jan 1986
TL;DR: In this paper, the authors propose a recursive least square adaptive filter (RLF) based on the Kalman filter, which is used as the unifying base for RLS Filters.
Abstract: Background and Overview. 1. Stochastic Processes and Models. 2. Wiener Filters. 3. Linear Prediction. 4. Method of Steepest Descent. 5. Least-Mean-Square Adaptive Filters. 6. Normalized Least-Mean-Square Adaptive Filters. 7. Transform-Domain and Sub-Band Adaptive Filters. 8. Method of Least Squares. 9. Recursive Least-Square Adaptive Filters. 10. Kalman Filters as the Unifying Bases for RLS Filters. 11. Square-Root Adaptive Filters. 12. Order-Recursive Adaptive Filters. 13. Finite-Precision Effects. 14. Tracking of Time-Varying Systems. 15. Adaptive Filters Using Infinite-Duration Impulse Response Structures. 16. Blind Deconvolution. 17. Back-Propagation Learning. Epilogue. Appendix A. Complex Variables. Appendix B. Differentiation with Respect to a Vector. Appendix C. Method of Lagrange Multipliers. Appendix D. Estimation Theory. Appendix E. Eigenanalysis. Appendix F. Rotations and Reflections. Appendix G. Complex Wishart Distribution. Glossary. Abbreviations. Principal Symbols. Bibliography. Index.
16,062Â citations
"Frequency domain equalization for s..." refers methods in this paper
...Adaptation can be done with LMS (least mean square), RLS, or least squares minimization (LS) techniques, analogous to adaptation of time domain equalizers [Hay96], [Cla98]....
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...Overlap-save or overlap-add signal processing techniques could also be used to avoid the extra overhead of the cyclic prefix [Fer85], [Hay96]....
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TL;DR: The analysis and simulation of a technique for combating the effects of multipath propagation and cochannel interference on a narrow-band digital mobile channel using the discrete Fourier transform to orthogonally frequency multiplex many narrow subchannels, each signaling at a very low rate, into one high-rate channel is discussed.
Abstract: This paper discusses the analysis and simulation of a technique for combating the effects of multipath propagation and cochannel interference on a narrow-band digital mobile channel. This system uses the discrete Fourier transform to orthogonally frequency multiplex many narrow subchannels, each signaling at a very low rate, into one high-rate channel. When this technique is used with pilot-based correction, the effects of flat Rayleigh fading can be reduced significantly. An improvement in signal-to-interference ratio of 6 dB can be obtained over the bursty Rayleigh channel. In addition, with each subchannel signaling at a low rate, this technique can provide added protection against delay spread. To enhance the behavior of the technique in a heavily frequency-selective environment, interpolated pilots are used. A frequency offset reference scheme is employed for the pilots to improve protection against cochannel interference.
2,627Â citations
"Frequency domain equalization for s..." refers background in this paper
...OFDM transmits multiple modulated subcarriers in parallel [ 1 ]....
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...Several variations of orthogonal frequency-division multiplexing (OFDM) have been proposed as effective anti-multipath techniques, primarily because of the favorable trade-off they offer between performance in severe multipath and signal processing complexity [ 1 ]....
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TL;DR: In this contribution the transmission of M-PSK and M-QAM modulated orthogonal frequency division multiplexed (OFDM) signals over an additive white Gaussian noise (AWGN) channel is considered and the degradation of the bit error rate is evaluated.
Abstract: In this contribution the transmission of M-PSK and M-QAM modulated orthogonal frequency division multiplexed (OFDM) signals over an additive white Gaussian noise (AWGN) channel is considered. The degradation of the bit error rate (BER), caused by the presence of carrier frequency offset and carrier phase noise is analytically evaluated. It is shown that for a given BER degradation, the values of the frequency offset and the linewidth of the carrier generator that are allowed for OFDM are orders of magnitude smaller than for single carrier systems carrying the same bit rate. >
1,816Â citations
TL;DR: This correspondence describes the construction of complex codes of the form exp i \alpha_k whose discrete circular autocorrelations are zero for all nonzero lags.
Abstract: This correspondence describes the construction of complex codes of the form exp i \alpha_k whose discrete circular autocorrelations are zero for all nonzero lags. There is no restriction on code lengths.
1,624Â citations