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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11 Dec 2006
TL;DR: This paper will discuss dynamic spectrum control techniques that can minimize intra- and inter-system interference for both multi-carrier (MC) and single- carrier (SC) systems, thereby maximizing upper-limit of channel capacity.
Abstract: This paper will discuss trend and our views on the flexible spectrum control and receiver performance improvement technologies as a part of capacity maximization technologies for beyond third generation (B3G) systems. First of all, we will discuss dynamic spectrum control techniques that can minimize intra- and inter-system interference for both multi-carrier (MC) and single-carrier (SC) systems, thereby maximizing upper-limit of channel capacity. We will also discuss receiver performance improvement strategies as a part of capacity maximization technologies for MC and SC systems, especially joint operation of the adaptive equalizer and decoder using EXIT chart analysis for MC and SC systems
17Â citations
Cites methods from "Frequency domain equalization for s..."
..., in the case of OFDM, inverse matrix multiplication is employed, whereas the frequency domain equalizer (FDE) [4] and frequency domain Turbo equalizer (FDTuE) [5] are employed for SC....
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07 May 2006
TL;DR: It is shown that the performance proposed receiver can be close to the single-user MFB (matched filter bound), even for fully loaded systems, in severely time-dispersive channel and/or in the presence of strong interfering signals.
Abstract: In this paper we consider the use of CP-assisted (Cyclic Prefix) DS-CDMA schemes (Direct Sequence Code Division Multiple Access) in broadband wireless systems. We present an iterative, frequency-domain MUD (MultiUser Detection) receiver for the uplink transmission that combines IB-DFE (Iterative Block Decision Feedback Equalization) principles with serial interference cancelation. It is shown that the performance of the proposed receiver can be close to the single-user MFB (Matched Filter Bound), even for fully loaded systems, in severely time-dispersive channels and/or in the presence of strong interfering signals.1
17Â citations
30 Nov 2004
TL;DR: In this article, a generalized OFDM (GOFDM) with frequency domain equalization (FDE) is proposed to alleviate the peak-to-average power ratio (PAPR) problem of OFDM.
Abstract: One of the main problems of orthogonal frequency division multiplexing (OFDM) is high peak-to-average power ratio (PAPR). In this paper, a novel approach to alleviate the PAPR problem of OFDM is presented. A generalized OFDM (GOFDM) with frequency-domain equalization (FDE) is proposed. Various FDE techniques based on zero forcing (ZF), maximum ratio combining (MRC) and minimum mean square error (MMSE) are considered. The bit error rate (BER) performance of GOFDM in a frequency-selective fading channel is evaluated by computer simulation and compared with those of conventional OFDM and single-carrier (SC) transmission
17Â citations
Cites methods from "Frequency domain equalization for s..."
...Viewing the GOFDM signal as a SC signal, we can apply various frequency domain equalization (FDE) techniques [ 5 ] based on zero forcing (ZF), maximal ratio (MR), and minimum mean square error (MM SE)....
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01 Dec 2003
TL;DR: Analytical comparison shows that at moderate- to-high signal-to-noise ratio (SNR), the uncoded error rate performance of multicarrier transmission is inferior to that of single carrier, and proposes new minimum bit error rate (MBER) power loading algorithms for multicarriers transmission.
Abstract: We compare cyclic prefix (CP) based single and multicarrier block transmission schemes in frequency-selective fading channels. Analytical comparison shows that at moderate-to-high signal-to-noise ratio (SNR), the uncoded error rate performance of multicarrier transmission is inferior to that of single carrier. We propose new minimum bit error rate (MBER) power loading algorithms for multicarrier transmission. It is also shown that a simpler approximate MBER (AMBER) power loading method has performance close to that of the optimum MBER scheme. Performance of a variety of methods is compared analytically and verified by simulations.
17Â citations
Cites background or methods from "Frequency domain equalization for s..."
...Recently, it has been shown that block SC transmission with similar block structure and frequencydomain equalization to CP-OFDM, has similar equalization complexity and performance as OFDM [2]....
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...for which there exist fast implementations based on FFT, also known as frequency-domain equalization [2]....
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22 Apr 2007
TL;DR: An efficient feedback design for single carrier frequency division multiple access (SC-FDMA) multiple input multiple output (MIMO) communication systems is described and a codebook-based approach for MIMO pre-coding and quantization of feedback information is considered.
Abstract: An efficient feedback design for single carrier frequency division multiple access (SC-FDMA) multiple input multiple output (MIMO) communication systems is described. We consider a codebook-based approach for MIMO pre-coding and quantization of feedback information. Differential processing is used to generate the updates iteratively for the feedback information between feedback instances. An approach of combined differential and non-differential feedback is considered for reduced feedback overhead and improved performance. A differential feedback with periodic error reset for differential processing is described. The performance of MIMO communication systems using pre-coding/transmit beamforming and the described feedback design is evaluated for SC-FDMA systems. The effects of pre-coding and feedback quantization, sub-carrier grouped feedback and feedback delay are investigated.
17Â citations
Cites background from "Frequency domain equalization for s..."
...The MIMO channels in frequency domain for a sub-carrier for two transmit and two receive antennas in a SC-FDMA system [11][12] can be expressed by a matrix,...
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References
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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