Frequency domain equalization for single-carrier broadband wireless systems

doi:10.1109/35.995852

Home
/
Papers
/
Frequency domain equalization for single-carrier broadband wireless systems

Journal Article•DOI•

Frequency domain equalization for single-carrier broadband wireless systems

David Falconer¹, S.L. Ariyavisitakul, A. Benyamin-Seeyar², B. Eidson³•Institutions (3)

Carleton University¹, Harris Corporation², Conexant³

01 Apr 2002-IEEE Communications Magazine (IEEE)-Vol. 40, Iss: 4, pp 58-66

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.

read less

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.

...read moreread less

Content maybe subject to copyright Report

Citations

PDF

Open Access

More filters

Journal Article•DOI•

Audio-band software-defined-radio approach to communication system design course

[...]

Jeng-Kuang Hwang¹, Yu-Lun Chiu¹, Rhi-Lung Chung¹, Chen-Yu Chen¹, Wei-Ming Chen¹, Chia-Shu Liao¹ - Show less +2 more•Institutions (1)

Yuan Ze University¹

01 Jul 2008-International Journal of Electrical Engineering Education

TL;DR: An innovative audio-band software-defined-radio (AB-SDR) approach is proposed for a design-oriented lab course on communication systems, which can help students to put abstract communication principles into practice, and gain an overview of communication systems design.

...read moreread less

Abstract: An innovative audio-band software-defined-radio (AB-SDR) approach is proposed for a design-oriented lab course on communication systems. By using a full-duplex sound card and Matlab software, the versatile AB-SDR platform facilitates the canonical top-down design flow at minimum cost. Illustrated by an orthogonal frequency division multiplexing (OFDM) transceiver design example, it is shown that almost every kind of communication system can be practically designed, simulated, realised, and tested in a systematic and flexible way. Since bandpass signals in audio band are generated in the real world, important design issues like receiver synchronisation and channel effects can be physically observed and tackled. Hence, the AB-SDR lab course can help students to put abstract communication principles into practice, and gain an overview of communication systems design.

...read moreread less

Performance of multi-rate equalizer with lte standard turbo code

[...]

Dongyang Du

01 Jan 2014

TL;DR: In this thesis, an algorithm is developed based on the construction pattern of the MRE to enable its realization and an LTE standard-compliant turbo code is simulated to evaluate the practical performance gains.

...read moreread less

Abstract: In the uplink channel of the 3GPP long term evolution (LTE) and LTEAdvanced (LTE-A) systems, signal carrier frequency-division multiplexing access (SC-FDMA) transmission scheme is employed instead of orthogonal frequency-division multiplexing (OFDM) to reduce the peak-to-average power ratio (PAPR). However, compared to OFDM, SC-FDMA has lower channel throughput, since it suffers from inter-symbol interference (ISI). Multi-rate equalizer (MRE) is a novel low complexity and non-linear equalizer which can increase the channel throughput. The basic idea of the MRE is that it first decomposes the single ISI channel into two parallel sub-channels by employing multi-rate signal processing and successive interference cancellation (SIC). Then, this decomposition procedure can be executed recursively to further increase the number of sub-channels. The ISI decreases as the number of sub-channels increases. Meanwhile, since the MRE does not require pre-coding, it does not increase PAPR. The practical implementation of the MRE is not straightforward. An algorithm, which can recursively call each function block in the MRE and execute the entire decomposition processes is required. In this thesis, an algorithm is developed based on the construction pattern of the MRE to enable its realization. An LTE standard-compliant turbo code is simulated to evaluate the practical performance gains of the MRE concept. MATLAB is selected as the simulation environment. According to the simulation results, the channel throughput can be increased by employing the MRE together with LTE turbo code indeed. One time-invariant and one timevarying channel model are employed. Three kinds of MRE with binary modulation are considered. Those are the MRE with two, four and eight subchannels. The increase in throughput is at least 25% and can reach 80% in highly frequency selective scenarios.

...read moreread less

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

...As a consequence, in SC-FDMA transmission, an equalizer is needed to combat the ISI [26] [19]....
[...]

Posted Content•

Performance Evaluation of Frequency Domain Equalisation Based Colour Shift Keying Modulation Schemes Over Diffuse Optical Wireless Channels

[...]

Ravinder Singh¹, Timothy O'Farrell, Thai C. Bui, Mauro Biagi, John P. R. David - Show less +1 more•Institutions (1)

University of Oxford¹

25 Mar 2019-arXiv: Signal Processing

TL;DR: The investigation results show that the FDE enables the higher order CSK modulation modes to achieve a bit error rate (BER) of 10\textsuperscript{-6} for finite amounts of optical power while operating over highly dispersive channels and hence provide data links of up to 85.33 and 256 Mbit/s through TLED and QLED CSK, respectively, for a system bandwidth of 24 MHz.

...read moreread less

Abstract: Multi-colour light-emitting diode (LED) based visible light communication (VLC) benefits from wavelength diversity while providing indoor illumination. Colour shift keying (CSK) is a well-researched IEEE standardised multi-colour VLC modulation technique. This paper presents an investigation into the performance of tri-chromatic LED (TLED) CSK standardised in IEEE 802.15.7 and a quad-chromatic LED (QLED) CSK, over a range of diffuse optical wireless channels, and proposes the use of frequency domain equalisation (FDE) at the receiver to combat multipath dispersion. The investigation results show that the FDE enables the higher order CSK modulation modes to achieve a bit error rate (BER) of 10\textsuperscript{-6} for finite amounts of optical power while operating over highly dispersive channels and hence provide data links of up to 85.33 and 256 Mbit/s through TLED and QLED CSK, respectively, for a system bandwidth of 24 MHz. The overall optical power requirements of the CSK schemes can be reduce by up to 12.6 dB with the use of FDE at the cost of a small overhead due to cyclic prefix. The optical channel model used in this investigation includes the cross-talk and insertion losses caused by the optical properties of commercially available system front end devices.

...read moreread less

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

...FDE is well known for providing a low complexity means to combat temporal dispersion, of a single carrier (SC) modulation based data signal, caused by multipath dispersion [16]....
[...]

Cooperative Diversity with STBC-OFDM

[...]

Kumagai Shinya, Nagaoka Ryo, Obara Tatsunori, Yamamoto Tetsuya, Adachi Fumiyuki - Show less +1 more

23 Aug 2012

TL;DR: This paper proposes a space-time block coded (STBC) cooperative diversity with receive frequency-domain equalization (FDE) in uplink and transmit FDE in downlink, respectively.

...read moreread less

Abstract: Abstract The transmission quality of the mobile terminal far from access points (APs) degrades due to the low received signal-to-noise power ratio (SNR). However, high transmission quality can be achieved even far from APs by operating cooperative diversity. In this paper, assuming the orthogonal frequency division multiplexing (OFDM) transmission, we propose a space-time block coded (STBC) cooperative diversity with receive frequency-domain equalization (FDE) in uplink and transmit FDE in downlink, respectively. The throughput performance of the STBC cooperative diversity is evaluated by computer simulation. Keyword STBC, cooperative diversity, OFDM

...read moreread less

Additional excerpts

...送受信信号表現本報告では，OFDM 伝送を仮定する．本章では，まず受信 FDE を用いる STBC 連携ダイバーシチの送受信系 (上りリンク )について述べ，次いで送信 FDE を用いる STBC 連携ダイバーシチの送受信系 (下りリンク )について述べる． 3.1....
[...]
...(12-a) ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ − + == )(ˆ)(ˆ )(ˆ)(ˆ )(ˆ * 1,00,1 * 1,10,0 2MT kYkY kYkY kNX (12-b) ⎟⎟ ⎟ ⎟ ⎠ ⎞ ⎜⎜ ⎜ ⎜ ⎝ ⎛ −− +− ++ == )(ˆ)(ˆ)(ˆ )(ˆ)(ˆ)(ˆ )(ˆ)(ˆ)(ˆ )(ˆ * 3,1 * 2,00,2 * 3,2 * 1,00,1 * 2,2 * 1,10,0 3MT kYkYkY kYkYkY kYkYkY kNX (12-c) ⎟⎟ ⎟ ⎟ ⎠ ⎞ ⎜⎜ ⎜ ⎜ ⎝ ⎛ +−− −+− +++ == )(ˆ)(ˆ)(ˆ)(ˆ )(ˆ)(ˆ)(ˆ)(ˆ )(ˆ)(ˆ)(ˆ)(ˆ )(ˆ 1,3 * 3,1 * 2,00,2 2,3 * 3,2 * 1,00,1 3,3 * 2,2 * 1,10,0 4MT kYkYkYkY kYkYkYkY kYkYkYkY kNX (12-d) ここで， )(ˆ , kY qm は )(ˆ up kY の第 (m,q)要素である．式 (12) のような復号を行うことで，周波数領域における第 j ブロックの軟判定出力 )(ˆ kX j は次式のように表せる． )(ˆ)()( 2 )(ˆ )up( 1 0 1 0 2 , MT NW MT kZkXkH TN E kX jj N n N m nm s s j += ∑ ∑ − = − = (13) ここで， )(ˆ )up( kZ j は復号後の等価雑音であり，平均 0，分散 2N0/Ts の複素ガウス変数である．このとき，チャネルの伝達関数{Hn,m(k)}が与えられたときの受信 SNR は次式で与えられる． { } ∑ ∑ − = − = =⎟⎟ ⎠ ⎞ ⎜⎜ ⎝ ⎛ 1 0 1 0 2 , 0MT , 0 up NW MT )(2)(,γ N n N m nm s nm s kH N E N kH N E (14) 式 (14)より，受信 FDE を用いる STBC 連携ダイバーシチは (NMT×NNW)次の最大比合成 (MRC)ダイバーシチ利得が得られることがわかる． 3.2....
[...]
...送信 FDE を用いる STBC 連携ダイバーシチ (a) 送信機 (AP) (b) 受信機 (端末 ) 図 3 送信 FDE を用いる STBC 連携ダイバーシチ図 3 に送信 FDE を用いる STBC 連携ダイバーシチの送受信系を示す．送信機 (AP)では，符号語ビット系列をデータ変調した後，Nc 個のデータシンボルからなる J 個のブロックに対して STBC を適用することで NMT×Q 個の符号化ブロックを得る．その後，送信重みを乗算する．なお，送信 FDE を用いる STBC 連携ダイバーシチでは，符号化率 Rt(=J/Q)を低下させることなく任意の数の AP を使用できる．一方で，端末アンテナ数を NMT...
[...]
...まえがき広帯域無線チャネルは，遅延時間の異なる複数の伝搬路から構成される周波数選択性フェージングチャネルである [1]．そのため，周波数選択性フェージングに起因する符号間干渉 (ISI)によって，伝送特性が劣化してしまう．直交周波数分割多重 (OFDM)[2]伝送は，周波数選択性フェージングチャネルにおいても優れた伝送特性と高い周波数利用効率を達成できる有効な手法として知られている．また，無線 LAN では，伝搬損失およびシャドウイング損失により，アクセスポイント (AP)から遠方に存在する端末の受信信号対雑音電力比 (SNR)が低下し，通信品質が劣化してしまう [1]．受信 SNR の改善には空間ダイバーシチ [1]が有効である．Alamouti 符号 [3]に代表される時空間ブロック符号 (STBC)を用いれば，簡易な処理で空間ダイバーシチ利得を得ることができる．受信周波数領域等化 (FDE)[4]を用いる STBC[5]は，符号化にチャネル情報 (CSI)を用いなくとも最大比送信ダイバーシチ利得が得られる技術であり，符号化率を低下させることなく任意の数の受信アンテナを使用できる．また，送信 FDE を用いる STBC[6]は CSI を用いる符号化を行う一方で，復号には CSI を必要としない技術であり，符号化率を低下させることなく任意の数の送信アンテナを使用できる．本報告では，OFDM 伝送を対象に，上りリンクに受信 FDE，下りリンクに送信 FDE をそれぞれ用いる STBC 連携ダイバーシチを提案する．提案する連携ダイバーシチは，従来独立に動作していた複数の AP を連携させることで CSI を用いる符号化あるいは復号をネットワーク側に集中させることができ，端末の簡素化が可能である．また，符号化率を低下させることなく任意の数の AP が連携することができるため，非常に高い空間ダイバーシチ利得を得ることができる．以上のことから，提案する STBC 連携ダイバーシチを無線 LAN に適用することにより，例えば災害時に近傍の AP が動作を停止してしまった端末の通信品質を改善できる．第 2 章では，本報告で検討を行う伝送モデルを示す．第 3 章では送信または受信 FDE を用いる STBC 連携ダイバーシチの送受信系を示す．第 4 章では計算機シミュレーションにより提案方式のスループット特性を明らかにし，第 5 章でまとめる． 2....
[...]
...むすび本報告では，OFDM 伝送を対象に，上りリンクに受信 FDE，下りリンクに送信 FDE をそれぞれ用いる STBC 連携ダイバーシチを提案した．提案した STBC 連携ダイバーシチは，CSI を用いる符号化あるいは復号をネットワーク側に集中させることができるので，端末の簡素化が可能である．また，任意の数の AP が連携することができるため，非常に高い空間ダイバーシチ利得を得ることができる．計算機シミュレーションにより，STBC 連携ダイバーシチを行う AP 数を増やすことで，特に AP から遠方に存在する端末のスループットを大幅に改善できることを明らかにした．このことから，提案した STBC 連携ダイバーシチを無線 LAN に適用することにより，例えば災害時に近傍の AP が動作を停止してしまった端末の通信品質を改善できると考えられる．謝辞本報告は，総務省の「情報通信ネットワークの耐災害性強化のための研究開発」（平成 23 年度補正予算（第 3 号））による委託を受けて実施した研究開発による成果である．文献 [1] A. Goldsmith, Wireless Communication , Cambridge University Press, 2005....
[...]

Journal Article•DOI•

Performance Evaluation of Joint MLD with Channel Coding Information for Control Signals Using Cyclic Shift CDMA and Block Spread CDMA

[...]

Teruo Kawamura¹, Ryota Takahashi², Hideyuki Numata², Nobuhiko Miki¹, Mamoru Sawahashi² - Show less +1 more•Institutions (2)

NTT DoCoMo¹, Tokyo City University²

01 Dec 2012-IEICE Transactions on Communications

TL;DR: Joint maximum likelihood detection using channel coding information for orthogonal code division multiple access (CDMA) to decrease the required average received signal-tonoise power ratio (SNR) satisfying the target block error rate (BLER), and investigates the effect of joint MLD from the conventional coherent detection associated with channel coding.

...read moreread less

Abstract: This paper presents joint maximum likelihood detection (MLD) using channel coding information for orthogonal code division multiple access (CDMA) to decrease the required average received signal-tonoise power ratio (SNR) satisfying the target block error rate (BLER), and investigates the effect of joint MLD from the conventional coherent detection associated with channel coding. In the paper, we assume the physical uplink control channel (PUCCH) as specified in Release 8 Long-Term Evolution (LTE) by the 3rd Generation Partnership Project (3GPP) as the radio interface for the uplink control channel. First, we clarify the best scheme for combining correlation signals in two frequency-hopped slots and in two receiver diversity branches for joint MLD. Then, we show that the joint MLD without channel estimation, in which correlation signals are combined in squared form, decreases the required average received SNR compared to that for joint MLD with coherent combining of the correlation signals using channel estimation. Second, we show the effectiveness of joint MLD in terms of the decrease in the required average received SNR compared to the conventional coherent detection in various delay spread channels. Third, we present a comparison of the average BLER performance levels between cyclic shift (CS)-CDMA and block spread (BS)CDMA using joint MLD. We show that when using joint MLD, BS-CDMA is superior to CS-CDMA due to a lower required received SNR in short delay spread environments and that in contrast, CS-CDMA provides a lower required received SNR compared to BS-CDMA in long delay spread environments. key words: CDMA, cyclic shift, block spread, MLD, LTE

...read moreread less

Collapse

References

PDF

Open Access

More filters

Book•

Adaptive Filter Theory

[...]

Simon Haykin

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.

...read moreread less

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.

...read moreread less

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 Article•DOI•

Analysis and Simulation of a Digital Mobile Channel Using Orthogonal Frequency Division Multiplexing

[...]

Jr. L.J. Cimini¹•Institutions (1)

Bell Labs¹

01 Jul 1985-IEEE Transactions on Communications

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.

...read moreread less

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.

...read moreread less

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•

Adaptive filter theory (2nd ed.)

[...]

Simon Haykin¹•Institutions (1)

McMaster University¹

01 Mar 1991

2,447 citations

Journal Article•DOI•

BER sensitivity of OFDM systems to carrier frequency offset and Wiener phase noise

[...]

Thierry Pollet¹, M. Van Bladel¹, Marc Moeneclaey¹•Institutions (1)

Ghent University¹

01 Feb 1995-IEEE Transactions on Communications

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.

...read moreread less

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. >

...read moreread less

1,816 citations

Journal Article•DOI•

Polyphase codes with good periodic correlation properties (Corresp.)

[...]

D. Chu¹•Institutions (1)

Hewlett-Packard¹

01 Jul 1972-IEEE Transactions on Information Theory

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.

...read moreread less

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.

...read moreread less

1,624 citations