scispace - formally typeset
Search or ask a question
Journal ArticleDOI

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.

Content maybe subject to copyright    Report

Citations
More filters
Journal ArticleDOI
TL;DR: An antenna-selection and ordering criterion that maximizes the signal-to-interference-plus-noise ratio (SINR) of the iterative receiver based on a soft decision that has been designed for EST-based modulation is proposed.
Abstract: In this paper, antenna selection and ordering for energy-spreading transform (EST)-based modulation employing multiple transmit antennas for cyclic delay diversity (CDD) is considered. First, we analyze the signal-to-interference-plus-noise ratio (SINR) of the iterative receiver based on a soft decision that has been designed for EST-based modulation. Then, an antenna-selection and ordering criterion that maximizes the SINR of the soft-decision receiver is proposed.

5 citations

Journal ArticleDOI
01 Sep 2018-Optik
TL;DR: It can be inferred from results that the PHN severely affects/deteriorates the performance of F–OFDM based communication systems in terms of high bit-error-rate (BER), when thePHN variations are large.

5 citations

Proceedings ArticleDOI
05 Mar 2008
TL;DR: A new block DFE structure is presented which iteratively improves itself and performs better as it increases the number of iterations and verify the supremacy of CP versions of SC-LE and SC-DFE overOFDM-CP and OFDM-ZP.
Abstract: Single Carrier Transmission (SCT) is a competing technique for Orthogonal Frequency Division Multiplexing (OFDM) in Broadband Wireless Systems (BWS). Recent developments in Frequency Domain Fqualization (FDE) using Decision Feedback Equalization (DFE) have greatly improved the system based on the SC technique. This paper presents the comparison of two different variants of both OFDM and SCT techniques, namely OFDM-Cyclic Prefix (OFDM-CP), OFDM-Zero Padding (OFDM-ZP), SC-CP and SC-ZP. SC variants are simulated with Linear Equalizer(LE) and DFE. We have simulated all four techniques for different flat and frequency selective channels. A new block DFE structure is presented which iteratively improves itself and performs better as we increase the number of iterations. Comparison results for BER simulations of both variants of OFDM and SC with LE and DFE verify the supremacy of CP versions of SC-LE and SC-DFE over OFDM-CP and OFDM-ZP.

5 citations


Cites background or methods from "Frequency domain equalization for s..."

  • ...Anti–Multipath approaches can be categorized as [6]...

    [...]

  • ...In order to improve the performance of SCFDE, it was proposed by [6] to use a DFE with timedomain feedback....

    [...]

  • ...[6] summarizes the attractive features of SC with FDE as under:...

    [...]

Proceedings ArticleDOI
29 Jul 2006
TL;DR: In this paper, the Doppler shift of the time-varying multi-path channel is estimated by calculating the expectation of the ACF (auto-correlation function) of the channel coefficient estimates on the effective fingers.
Abstract: In this paper, the Doppler shift of the time-varying multi-path channel is estimated by calculating the expectation of the ACF (auto-correlation function) of the channel coefficient estimates on the effective fingers. Furthermore we analyze the estimation bias and propose an improved estimation method based on SNR (signal-to-noise ratio) estimation to obtain the high estimation accuracy in wide ranges of velocities and SNRs.

5 citations

Journal ArticleDOI
Justin P. Coon1
TL;DR: In this article, a novel method of performing interference avoidance in next-generation single-carrier ultrawideband block transmission systems is presented, where the application of a time-domain window to each data block prior to transmission is relied on.
Abstract: In this article, a novel method of performing interference avoidance in next-generation single-carrier ultrawideband block transmission systems is presented. This method relies on the application of a time-domain window to each data block prior to transmission, where the window is optimized such that the required notch depth is achieved for each transmission. Furthermore, a modification of this technique is also detailed, whereby the complexity can be reduced from O(N3) to O(N2) where N is the number of symbols per block. It is shown that the proposed techniques overcome many of the drawbacks of current methods such as transmit power control, frequency notching, and active interference cancellation.

5 citations

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]....

    [...]

Journal ArticleDOI
Jr. L.J. Cimini1
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 ]....

    [...]

Book
Simon Haykin1
01 Mar 1991

2,447 citations

Journal ArticleDOI
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

Journal ArticleDOI
D. Chu1
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