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
More filters
01 Aug 2019
TL;DR: Computer simulation results show that the proposed symbol timing detection method achieves almost the same bit error rate performance as that for the phase-locked loop employing Gardner's timing error detection for FDE in single-carrier LOS-MIMO in Rummler fading channels.
Abstract: This paper proposes a symbol timing detection method based on the measured cross-correlation power, i.e., power delay profile, of a pilot sequence for frequency domain equalization (FDE) in single-carrier line-of-sight (LOS) - multiple-input multiple-output (MIMO) transmission. In the proposed method, we detect the best symbol timing that provides the maximum cross-correlation power between the received signal being oversampled with an $N$ times fast Fourier transform (FFT) sampling rate and the pilot sequence replica in the initial acquisition mode. Subsequently, in the tracking mode, we detect the best symbol timing from the maximum cross-correlation power of the pilot sequence at the Lagrange interpolation filter output in a frequency-selective fading channel. Based on computer simulation, we optimize the averaging time of the measured cross-correlation power and the update interval that are used to update the symbol timing in the interpolation filter with the double sampling rate of the FFT sample rate. Computer simulation results show that the proposed symbol timing detection method achieves almost the same bit error rate performance as that for the phase-locked loop employing Gardner's timing error detection for FDE in single-carrier LOS-MIMO in Rummler fading channels.
Additional excerpts
...So far, the required received signal-to-noise power ratio (SNR) satisfying the target symbol error rate has been investigated using time domain equalization (TDE) with the minimum mean square error (MMSE) algorithm for LOS-MIMO in a frequency-selective fading channel [5]....
[...]
...Frequency domain equalization (FDE) was proposed by taking advantage of the feature of lower computational complexity compared to TDE [6]....
[...]
01 Sep 2014
TL;DR: This paper takes a study on a dual-mode (DD-LMS+MCMA) blind equalization algorithm applied in a single-carrier system and builds the simulation model of image transmission in SC-FDE system and gets the direct and better result through the comparative analysis of image.
Abstract: The traditional equalization technologies expose some shortages while people put forward higher demand to quality of communication system and transmission rate. Single-carrier frequency-domain equalization SC-FDE is becoming a research hotspot in wideband wireless communication area because of its special predominance. In recent years, the research on SC-FDE develops quickly. We take a study on feasibility of building SC-FDE system by comparing performance with orthogonal frequency division multiplexing. This paper takes a study on a dual-mode direct decision-least mean square+modify constant modulus algorithm blind equalization algorithm applied in a single-carrier system. And then, we build the simulation model of image transmission in SC-FDE system and get the direct and better result through the comparative analysis of image. Copyright © 2012 John Wiley & Sons, Ltd.
22 Apr 2007
TL;DR: Simulations demonstrate that high performance can be achieved by using the proposed detection with virtual antennas for fractionally spaced frequency-domain equalizer for the single carrier MIMO-CDMA systems.
Abstract: This paper proposes a new approach to apply fractionally spaced frequency-domain equalizer (FSFDE) for the single carrier MIMO-CDMA systems. The complexity of this equalizer can be significantly reduced with the help of performing the equalization in the frequency domain. Analogous to the previously developed layered space-time architectures, we proposed layered space-frequency detection (LSFD) which is performed layer by layer in a successive way. In this work, the concept of virtual antennas is also introduced. Oversampling at the receiver is equivalent to having multiple virtual receive antennas with the correlated channel gains and the colored noise. This may be viewed as a virtual receive diversity, and therefore, each polyphase component is denoted as a virtual antenna. Simulations demonstrate that high performance can be achieved by using the proposed detection with virtual antennas.
Cites background from "Frequency domain equalization for s..."
...Two most promising detecting approaches for the future broadband wireless communication systems are single carrier frequency-domain equalizer (SCFDE) [1], [2] and orthogonal frequency division multiplexing (OFDM) [3]....
[...]
20 Feb 2013
TL;DR: DAN のエネルギー利用効率を向上させる有効な技術として, 下してしまう,CAN の無線ネットワーク(CAN)では,伝搬損失によって特にセル端での受信信号�
Abstract: あらまし アンテナが無線セル中央の基地局に集中配置されている従来の無線ネットワーク(集中アンテナネッ トワーク(CAN)と呼ぶ)では,伝搬損失によって特にセル端での受信信号電力が極端に低下し,周波数利用効率が低 下してしまう.周波数利用効率を向上させる有効な技術として,無線セル内に多数のアンテナを分散配置させる分 散アンテナネットワーク(DAN)がある.DAN では移動端末が高確率で距離の近い分散アンテナと通信出来るため, 無線セル全域にわたって高い受信信号電力を獲得でき,特に無線セル端において周波数利用効率を改善できる.と ころで,所要の伝送品質を確保するためには伝送速度に比例して送信電力を増大させる必要があるが,エネルギー 資源は限られており,その有効利用が求められる.DAN では移動端末とアンテナ間の距離が近くなるため,所要の 受信電力を CAN より低い送信電力で達成でき,高いエネルギー利用効率を達成できると考えられる.本稿では, 下りリンク DAN のエネルギー利用効率をモンテカルロ数値計算により明らかにし,CAN との比較を行う. キーワード 分散アンテナ,エネルギー利用効率,周波数利用効率
03 Dec 2015
TL;DR: Through the comprehensive analysis of mean-square-error (MSE), it is shown that, unlike the point-to-point communications, the imperfection of the channel knowledge leads to the unstable performance of channel equalization under the condition of high quality reception from relay- to-destination link.
Abstract: In this paper, we analyze the effect of the imperfect channel estimation on the equalization performance in three-node cooperative wireless networks. Specifically, we consider a distributed time-reversal space-time block coded single-carrier (D-TR-STBC-SC) system over frequency-selective fading channels with amplify-and-forward (AF) half-duplex relaying. Through the comprehensive analysis of mean-square-error (MSE), it is shown that, unlike the point-to-point communications, the imperfection of the channel knowledge leads to the unstable performance of channel equalization under the condition of high quality reception from relay-to-destination link. The analytical results show the main reason for such phenomenon. The validity of the theoretical analysis is demonstrated through the computer simulations.
Additional excerpts
...inter-symbol interference (ISI) [10]-[11]....
[...]
...0J. M. Choi and J. S. Seo are with Department of Electrical and Electronic Engineering, Yonsei University, Seoul 120-749, Korea (e-mail: choi jm@yonsei.ac.kr, jsseo@yonsei.ac.kr). inter-symbol interference (ISI) [10]-[11]....
[...]
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]....
[...]
...Overlap-save or overlap-add signal processing techniques could also be used to avoid the extra overhead of the cyclic prefix [Fer85], [Hay96]....
[...]
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 ]....
[...]
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