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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20 Oct 2010
TL;DR: PACE-PACE を用いる繰り返しチャネル推定(SI-Pace)に重点を置きながら,それと時間多重パイロットとウィナーフィルタを用 いるチャ neutraceuticals(PACE)
Abstract: あらまし 複数受信ブロックにわたるサイズのウィナーフィルタをスライディングさせながらチャネル推定を 行う,パイロットとウィナーフィルタを用いるシングルキャリア繰り返しチャネル推定は,精度良く自己相関関数 を推定でき,十分長いサイズのウィナーフィルタよりも演算量を抑えながら,チャネル変動への高い追従能力を有 している.パイロットには重畳型と時間多重型の 2 つがある.本論文では,重畳型パイロットとウィナーフィルタ を用いる繰り返しチャネル推定(SI-PACE)に重点を置きながら,それと時間多重パイロットとウィナーフィルタを用 いるチャネル推定(TM-PACE)をシングルキャリアハイブリッド自動再送要求(SC HARQ)に適用した時のスループッ ト特性を計算機シミュレーションで求め,SI-PACE と TM-PACE とを比較している. キーワード 重畳型パイロット,ウィナーフィルタ,自己相関推定,HARQ
06 May 2012
TL;DR: An iterative channel estimation and equalization scheme for single-carrier systems is proposed, realizing space-frequency block code (SFBC) with amplify-and-forward (AF) relaying in a distributed fashion.
Abstract: Cooperative diversity is an effective transmission technique allowing multiple users to create a virtual antenna array although each of them is equipped with single antenna. In this paper, an iterative channel estimation and equalization (ICEE) scheme for single-carrier systems is proposed, realizing space-frequency block code (SFBC) with amplify-and-forward (AF) relaying in a distributed fashion. Most existing researchers assume perfect channel information available at the receiver, however, the effect of imperfect channel estimation should be considered for practical applications. In the proposed algorithm, pilot-aided channel estimation (CE) and soft inter-symbol interference (ISI) cancelation with minimum mean squared error (MMSE) filtering are performed iteratively to suppress interferences. An implementation that accounts for imperfect channel estimation is also investigated. The bit error rate (BER) performances and extrinsic information transfer (EXIT) charts are presented for Rayleigh fading channels. Simulation results demonstrate the effectiveness of the proposed algorithm.
Cites background from "Frequency domain equalization for s..."
...Moreover, SC-FDE does not suffer high peak-to-average power ratio (PAPR) as well as sensitivity to frequency and phase offsets, thus alleviating the nonlinear distortion and carrier synchronization problems inherent to OFDM [2]....
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...Recently, SCFDE has drawn a great attention as an alternative to OFDM....
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...Index Terms—channel estimation, equalization, iterative detection, relay, SFBC I. INTRODUCTION Single-carrier frequency-domain equalization (SC-FDE) has similar performance and complexity compared with orthogonal frequency division multiplexing (OFDM) [1]....
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...Single-carrier frequency-domain equalization (SC-FDE) has similar performance and complexity compared with orthogonal frequency division multiplexing (OFDM) [1]....
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Patent•
19 Dec 2008
TL;DR: In this paper, the authors concerne un dispositif de reception which recoit un signal emis par un disposITif d'emission which modifie le procede de modulation and/ou le taux d'encodage.
Abstract: L'invention concerne un dispositif de reception qui recoit un signal emis par un dispositif d'emission qui modifie le procede de modulation et/ou le taux d'encodage. Le dispositif de reception comprend : une unite d'egalisation qui egalise un signal de reception dans une region de frequence ; une unite de calcul de fiabilite qui calcule une fiabilite des bits d'emission a partir du signal de reception apres son egalisation ; une unite de calcul de quantite d'informations mutuelles qui calcule une quantite d'informations mutuelles en fonction de la fiabilite des bits d'emission calculee par l'unite de calcul de fiabilite ; et une unite de generation de signal de rapport qui etablit le procede de modulation et/ou le taux d'encodage en fonction de la quantite d'informations mutuelles calculee par l'unite de calcul de quantite d'informations mutuelles et qui genere un signal pour rapporter celui qui a ete selectionne au dispositif d'emission.
01 Jul 2015
TL;DR: In this article, the performance of an interference aware iterative block decision feedback equalizer (IBDFE) for the uplink of LTE-Advanced with single carrier (SC) transmissions is studied.
Abstract: In this paper we study the performance of an interference aware iterative block decision feedback equalizer (IBDFE) for the uplink of LTE-Advanced with single carrier (SC) transmissions. The receiver makes use of the correlation between the interference in the receiving antennas and minimizes the mean squared error (MMSE) of the detected symbols. Link level simulation results show that the proposed receiver clearly outperforms the conventional IBDFE and the linear interference rejection combining (IRC) detector. System level simulation results show that the use of the new iterative receiver achieves additional throughput gains. However, the gains obtained depend on the schedulers employed and on the number of receiving antennas.
Cites methods from "Frequency domain equalization for s..."
...In order to tackle the inter symbol interference (ISI) caused by the channel time dispersion, 4G networks use orthogonal frequency division multiplexing (OFDM) [1] or SC [2] transmission techniques....
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01 Oct 2012
TL;DR: Simulation results show that the proposed algorithm has comparable performance with the time variant one with frequency domain equalization, and outperforms the algorithm with its equalizer operating in the time domain.
Abstract: In this paper, BICM-ID technique is combined with frequency domain decision feedback turbo equalization to improve the BER performance over multi-path fading channels, and the coefficients of the equalization filters, i.e., feedforward filter and feedback filter, are designed time invariant to reduce computational complexity. Simulation results show that the proposed algorithm has comparable performance with the time variant one with frequency domain equalization, and outperforms the algorithm with its equalizer operating in the time domain.
Cites methods from "Frequency domain equalization for s..."
...This technique has been paid considerable attention in continuous phase modulation (CPM) [2], multi-input multi-output (MIMO) [3] systems, and so forth....
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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.
16,062 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.
2,627 citations
"Frequency domain equalization for s..." refers background in this paper
...OFDM transmits multiple modulated subcarriers in parallel [ 1 ]....
[...]
...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. >
1,816 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.
1,624 citations