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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TL;DR: This paper proposes a joint use of Tomlinson-Harashima precoding (THP) and FDE to remove the residual ISI and presents an approximate conditional BER analysis for the given channel condition.
Abstract: The performance of single-carrier (SC) transmission in a frequency-selective fading channel degrades due to a severe inter-symbol interference (ISI). Using frequency-domain equalization (FDE) based on the minimum mean square error (MMSE) criterion can improve the bit error rate (BER) performance of SC transmission. However, the residual ISI after FDE limits the performance improvement. In this paper, we propose a joint use of Tomlinson-Harashima precoding (THP) and FDE to remove the residual ISI. An approximate conditional BER analysis is presented for the given channel condition. The achievable average BER performance is evaluated by Monte-Carlo numerical computation method using the derived conditional BER. The BER analysis is confirmed by computer simulation of the signal transmission.
30 citations
Additional excerpts
...Using frequency-domain equalization (FDE) based on the minimum mean square error (MMSE) criterion can improve the bit error rate (BER) performance of SC transmission....
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TL;DR: This paper investigates the performance of multi-antenna SC-FDE under cyclic-delay diversity (CDD) and Alamouti signaling, and shows that at high rates the CDD diversity degenerates to the diversity of the SISO SC-fDE, while Alam outi signaling provides twice the diversity.
Abstract: Single-carrier (SC) block transmission with cyclic prefix (CP) is a method with several advantages that has been incorporated into standards. This paper investigates the performance of multi-antenna SC-FDE under cyclic-delay diversity (CDD) and Alamouti signaling. Our analysis fully characterizes the diversity, showing that it depends not only on the antenna configuration and channel memory, but also on data block length and data transmission rate. Below a certain rate threshold, full diversity is available to both CDD and Alamouti signaling, while at higher rates their diversity diminishes, albeit not quite in the same way. Our analysis shows that at high rates the CDD diversity degenerates to the diversity of the SISO SC-FDE, while Alamouti signaling provides twice the diversity of SISO SC-FDE.
30 citations
Additional excerpts
...…Frequency-Domain Equalizer with Multi-Antenna Transmit Diversity Ahmed Hesham Mehana, Student Member, IEEE, and Aria Nosratinia, Fellow, IEEE Abstract—Single-carrier (SC) block transmission with cyclic prefix (CP) is a method with several advantages that has been incorporated into standards....
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TL;DR: Broadband, all-optical wavelength conversion over 100 nm span, in full S- and C-band, with positive conversion efficiency with low optical input power exploiting dual pump Four-Wave-Mixing in a Quantum Dot Semiconductor Optical Amplifier (QD-SOA).
Abstract: We report broadband, all-optical wavelength conversion over 100 nm span, in full S- and C-band, with positive conversion efficiency with low optical input power exploiting dual pump Four-Wave-Mixing in a Quantum Dot Semiconductor Optical Amplifier (QD-SOA). We also demonstrate by Error Vector Magnitude analysis the full transparency of the conversion scheme for coherent modulation formats (QPSK, 8-PSK, 16-QAM, OFDM-16QAM) in the whole C-band.
30 citations
01 Dec 2011
TL;DR: The recent advances in single-carrier DAN are introduced and many new ideas in spatial multiplexing, diversity, array, or relaying technique are introduced.
Abstract: For the realization of future wireless networks, gigabit wireless technology, which can achieve higher-than-1 Gbps data transmission with extremely low transmit power, is indispensable. We have been studying the distributed antenna network (DAN) and the frequency domain wireless signal processing. In DAN, many antennas or clusters of antennas are spatially distributed over a service area, and they are connected by means of optical fiber links with DAN signal processing center. A number of distributed antennas cooperatively serve mobile users using spatial multiplexing, diversity, array, or relaying technique. In this paper, the recent advances in single-carrier DAN are introduced. Copyright © 2011 John Wiley & Sons, Ltd.
30 citations
TL;DR: This paper develops a simple technique for blind channel estimation that does not need redundant precoding or virtual carriers, and provides bandwidth efficiency and the phase ambiguity, which is an inherent problem in traditionalblind channel estimation, is reduced to sign ambiguity only.
Abstract: In this paper, we consider blind channel estimation for cyclic-prefixed single-carrier (CP-SC) systems via second-order statistics only. By exploiting the existence of real symbols in the transmitted data block, we develop a simple technique for blind channel estimation that does not need redundant precoding or virtual carriers. Hence, the proposed algorithm provides bandwidth efficiency. A side benefit of the proposed algorithm is that the phase ambiguity, which is an inherent problem in traditional blind channel estimation, is reduced to sign ambiguity only. This side benefit facilitates signal detection in digital communications where symbols are usually taken from a finite alphabet. Although the proposed method is mainly developed for channel estimation in single-input-single-output CP-SC systems, it can also be applied straightforwardly to single-input-multiple-output systems (either with CP-SC or other kinds) and multiple-input-multiple-output systems whenever real symbols exist or are deliberately inserted in the transmission.
30 citations
Cites background from "Frequency domain equalization for s..."
...CYCLIC-PREFIXED single-carrier (CP-SC) communication with frequency-domain equalization (SC-FDE) [1]–[4] has recently received more attention since it has nearly all the advantages of orthogonal frequency-division multiplexing (OFDM)1 but offers significant performance improvements over OFDM in certain environments....
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...In addition, since the peak-to-average power ratio (PAPR) in SC-FDE is much smaller, more powerefficient transmitters can be used....
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...SC-FDE delivers performance similar to OFDM with essentially the same overall complexity [1]....
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...As stated in [1], the SC-FDE approach has essentially the same performance and low complexity as an OFDM system but does not suffer from the PAPR problem....
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...I. INTRODUCTION CYCLIC-PREFIXED single-carrier (CP-SC) communi-cation with frequency-domain equalization (SC-FDE) [1]–[4] has recently received more attention since it has nearly all the advantages of orthogonal frequency-division multiplexing (OFDM)1 but offers significant performance improvements over OFDM in certain environments....
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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 ]....
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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. >
1,816 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