Preview

Comparison and Analysis of Channel Estimation Algorithms in Ofdm Systems

Powerful Essays
Open Document
Open Document
2467 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Comparison and Analysis of Channel Estimation Algorithms in Ofdm Systems
Comparison And Analysis Of Channel Estimation Algorithms In OFDM Systems
Vineetha Mathai
Dept. of Electronics Engineering, Madras Institute of Technology, Chennai-600044, India. e-mail: vineethamathai@yahoo.in

Abstract—The channel estimation can be performed for analyzing effect of channel on signal by either inserting pilot tones into all of the subcarriers of OFDM symbols with a specific period or inserting pilot tones into each OFDM symbol. The block type pilot channel estimation has been developed under the assumption of slow fading channel. When the data is transmitted at high bit rates, the channel impulse response can extend over many symbol periods, it leads to inter symbol interference. Orthogonal Frequency Division Multiplexing is one of the promising candidate to mitigate the ISI. This work improved various channel performance measures based on the comparison of various channel estimation algorithms and suggest a new technique which provides better performance. Keywords-OFDM, Block Pilot symbols, Channel estimation, Linear minimum mean square error (LMMSE), Mean square error (MSE), Bit error rate (BER)

based estimation came into our preference. In this method, the transmitted signal is known at the receiver. There are two modes: the block pilot mode and the comb pilot mode. In the block pilot mode, all the subcarriers of an OFDM symbol are dedicated to the known pilots. In the comb pilot mode, only a few subcarriers are used for the initial estimation process. II. CHANNEL ESTIMATION

I.

INTRODUCTION

Orthogonal Frequency Division Multiplexing is a very attractive technique for high bit-rate transmission in 4G wireless communication systems, where bandwidth is very precious, and service providers are continuously met with the challenges of including more number of users with in a limited allocated bandwidth. OFDM is a multicarrier modulation technique which provides an efficient means to handle high speed data streams on a multipath fading



References: [1] Geng Nian, Xiaojun Yuan and Li Ping, "DualDiagonal LMMSE Channel Estimation for OFDM Systems”, IEEE Trans.on Communication, pp.1420, November 2011. [2] Aida Zaier and Ridha Bouallègue,"Channel Estimation Study For Block-Pilot Insertion In OFDM Systems Under Slowly Time Varying Conditions”, International Journal of Computer Networks & Communications (IJCNC) Vol.3, No.6, November 2011. [3] Lie Ma, Hua Yu and Shouyin Liu, "The MMSE Channel Estimation Based on DFT for OFDM System", IEEE Trans.on Communication, pp. 1-4, October 2009. [4] M. Faulkner, "The effect of filtering on the performance of OFDM systems", IEEE Trans. on Vehicular Technology, vol. 49, September 2000. [5] Y. Qiao, S. Yu, P. Su, and L. Zhang, "Research on an interative algorithm of Is channel estimation in MIMO OFDM systems", IEEE Trans., Broadcast., vol. 51, pp. 149-153, March 2005. [6] S. Coleri, M. Ergen, A. Puri, and A. Bahai, “Channel estimation techniques based on pilot arrangement in OFDM systems”, IEEE Transactions on Broadcasting, vol.48, pp. 223-229, Sept. 2002. [7] J.-C. Lin, “Least-squares channel estimation for mobile OFDM communication on time-varying frequency- selective fading channels”, IEEE Transactions on Vehicular Technology, vol. 57, pp. 3538–3550, 2008. [8] M. Noh, Y. Lee and H. Park,” Low complexity LMMSE channel estimation for OFDM”, IEEE Proc. Commun., Vol. 153, October 2006. Figure 4. MSE curve for various estimation algorithms Figure 5. BER curve for various estimation algorithms CONCLUSION The channel is estimated using least square (LS), minimum mean-square error (MMSE), DFT based channel estimation, linear minimum mean square error (LMMSE), dual diagonal linear minimum mean square error (DDLMMSE), Proposed Method. The performance of the proposed method is closed to the ideal LMMSE estimation and better than the LS and DFT based CE, because it uses the channel autocorrelation matrix and the noise variance which was estimated in the LMMSE algorithm. At high SNR, the performance of the proposed method is much better. Since the effect of the noise is also small, hence the In

You May Also Find These Documents Helpful

  • Satisfactory Essays

    Midterm Test

    • 562 Words
    • 3 Pages

    Department of Electrical and Computer Engineering ELE635 - Communication Systems - Spring 2012 Midterm Test…

    • 562 Words
    • 3 Pages
    Satisfactory Essays
  • Powerful Essays

    Code Division Multiple Access is a new technology used in wireless communication devices. This technology made its commercial debut in the early nineties. Significant advantage of the CDMA is the fact that unlike other modulation schemes it does not have to allocate part of the frequency for each user. It allocates whole frequency spectrum to each user, distinguishing each signal with the unique pseudo-random sequence.…

    • 2922 Words
    • 12 Pages
    Powerful Essays
  • Powerful Essays

    OFDM Channel Estimation

    • 30099 Words
    • 121 Pages

    [14] H. Arslan and G. E. Bottomley, “Channel Estimation in Narrowband Wireless Communication Systems,” Wireless Commun. and Mobile Comp., vol. 1, no. 2, Apr. 2001, pp. 201–19.…

    • 30099 Words
    • 121 Pages
    Powerful Essays
  • Better Essays

    Ofdm

    • 4596 Words
    • 19 Pages

    References: [1] Van Nee R, Prasad R. OFDM for wireless multimedia communications. London: Artech House Publishers; 2000. [2] Bahai ARS, Saltzberg BR. Multi-carrier digital communications: theory and applications of OFDM. New York: Kluwer Academic/Plenum; 1999. [3] Cimini LJ. Analysis and simulation of a digital mobile channel using orthogonal frequency division multiplexing. IEEE Trans Commun 1985;33:665–75. [4] Pollet T, Van Bladel M, Moeneciaey M. BER sensitivity of OFDM system to carrier frequency offset and Wiener phase noise. IEEE Trans Commun 1993;43:191–3. [5] Moose P. A Technique for orthogonal frequency division multiplexing offset correction. IEEE Trans Commun 1994;42:2908–14. [6] Russell M, Stüber GL. Interchannel interference analysis of OFDM in a mobile environment. In: Proceedings of IEEE vehicular technology conference, vol. 2, Chicago, IL, July 1995. p. 820–4. [7] Yuping Zhao, Sven-Gustav Haggman. Sensitivity to Doppler shift and carrier frequency errors in OFDM systems:…

    • 4596 Words
    • 19 Pages
    Better Essays
  • Powerful Essays

    Dvb Technologies

    • 6202 Words
    • 25 Pages

    Over the last ten years digital technology has encouraged a rapid growth in the personal consumption of media. The advent of personal video recorders (PVRs), video-on-demand and the multiplication of program offerings have enabled viewers to personalize the content that they want to watch. And with interactivity, viewers can directly express their preferences to broadcasters.…

    • 6202 Words
    • 25 Pages
    Powerful Essays
  • Better Essays

    No Sweat wants to sell clothes on a new market. Sasja Schaap has gathered information and made a pre-selection of three interesting markets, namely Belgium, Germany and Denmark. These three countries offer the biggest potential to start exporting to. This is based on facts and figures about the market, trends and other factors. Each market has its pros and cons.…

    • 1554 Words
    • 7 Pages
    Better Essays
  • Powerful Essays

    equaliser

    • 1467 Words
    • 6 Pages

    y k = ∑ w  ∑ hn x k −n−m v k −m …

    • 1467 Words
    • 6 Pages
    Powerful Essays
  • Powerful Essays

    Lte Scheduling

    • 20131 Words
    • 81 Pages

    Abstract Future generation cellular networks are expected to provide ubiquitous broadband access to a continuously growing number of mobile users. In this context, LTE systems represent an important milestone towards the so called 4G cellular networks. A key feature of LTE is the adoption of advanced Radio Resource Management procedures in order to increase the system performance up to the Shannon limit. Packet scheduling mechanisms, in particular, play a fundamental role, because they are responsible for choosing, with fine time and frequency resolutions, how to distribute radio resources among different stations, taking into account channel condition and QoS requirements. This goal should be accomplished by providing, at the same time, an optimal trade-off between spectral efficiency and fairness. In this context, this paper provides an overview on the key issues that arise in the design of a resource allocation algorithm for LTE networks. It is intended for a wide range of readers as it covers the topic from basics to advanced aspects. The downlink channel under frequency division duplex configuration is considered as object of our study, but most of the considerations are valid for other configurations as well. Moreover, a survey on the most recent techniques is reported, including a classification of the different approaches presented in literature. Performance comparisons of the most well-known schemes, with particular focus on QoS provisioning capabilities, are also provided for complementing the described concepts. Thus, this survey would be useful for readers interested in learning the basic concepts before going into the details of a particular scheduling strategy, as well as for researchers aiming at deepening more specific aspects.…

    • 20131 Words
    • 81 Pages
    Powerful Essays
  • Good Essays

    Software Defined Radios

    • 996 Words
    • 4 Pages

    l Software Defined Radio Theoretical Analysis and Design, Regulagadda Srinivasa Adiya and Suresh Angadi, International Journal of Engineering Trends and Technology (IJETT), Volume 4, Issue 5, May 2013…

    • 996 Words
    • 4 Pages
    Good Essays
  • Good Essays

    Signal Processing

    • 8836 Words
    • 36 Pages

    References: [1] T. W. Anderson, An Introduction to Multivariate Statistical Analysis, 2nd ed. New York: Wiley, 1984. [2] J. Chen and U. Mitra, “Optimum near–far resistance for dual-rate DS/CDMA signals: Random signature sequence analysis,” IEEE Trans. Inform. Theory, vol. 45, pp. 2434–2447, Nov. 1999. [3] V. L. Hansen, Fundamental Concepts in Modern Analysis. Singapore: World Scientific, 1999. [4] M. Honig, U. Madhow, and S. Verdú, “Blind adaptive multiuser detection,” IEEE Trans. Inform. Theory, vol. 41, pp. 944–960, July 1995. [5] M. L. Honig and W. Xiao, “Large system performance of reduced-rank linear filters,” in Proc. 37th Annu. Allerton Conf. Communications, Computing and Control, Monticello, IL, Sept. 1999. [6] U. Madhow and M. L. Honig, “On the average near–far resistance for MMSE detection of direct sequence CDMA signals with random spreading,” IEEE Trans. Inform. Theory, vol. 45, pp. 2039–2045, Sept. 1999. [7] H. V. Poor and S. Verdú, “Probability of error in MMSE multiuser detection,” IEEE Trans. Inform. Theory, vol. 43, pp. 858–871, May 1997. [8] P. Schramm and R. R. Müeller, “Spectral efficiency of CDMA systems with linear MMSE interference suppression,” IEEE Trans. Commun., vol. 47, pp. 722–731, May 1999. [9] G. S. Rogers, Matrix Derivatives, Lecture Notes in Statistics. New York: Marcel Dekker, 1980, vol. 2. [10] R. J. Serfling, Approximation Theorems of Mathematical Statistics. New York: Wiley, 1980. [11] D. N. C. Tse and S. Hanly, “Linear multiuser receivers: Effective interference, effective bandwidth and user capacity,” IEEE Trans. Inform. Theory, vol. 45, pp. 641–657, Mar. 1999.…

    • 8836 Words
    • 36 Pages
    Good Essays
  • Better Essays

    Review Paper

    • 5588 Words
    • 23 Pages

    To design optical OFDM using low bandwidth electronics and optoelectronics components,also low loss comb-line combiner using the IFFT,lightware centralized Bidirectional hybrid Acess network and also with remodulated ONUS and a coherent receiver OLT ,various technique to control PAPR(peak to average power ratio),different types of modulation methods with pre-emphasis technique, an idea abot MAMSK-OFDM technology for next generation,putting the Doppler shift into usuage into intelligent transportation system,comparison between different types of modulation scheme and OFDM,directly modulated signal transmission over fiber in WDM –PON…

    • 5588 Words
    • 23 Pages
    Better Essays
  • Good Essays

    Transmit Diversity

    • 7383 Words
    • 30 Pages

    [3] P. Viswanath, D. N. C. Tse, and R. Laroia, “Opportunistic beamforming using dumb antennas,” IEEE Transactions on Information Theory, vol. 48, pp. 1277–1294, June 2002. [4] D. Tse and P. Viswanath, “Fundamentals of wireless communication.” Lecture Notes for EE 290S, U.C. Berkeley, Fall 2002. [5] E. Telatar, “Capacity of multi-antenna gaussian channels,” European Transactions on Telecommunications, vol. 10, pp. 585–595, November 1999. [6] S. Haykin, Adaptive Filter Theory. Prentice Hall, 4th ed., 2002. [7] A. T. James, “Distributions of matrix variates and latent roots derived from normal samples,” Annals of Mathematical Statistics,, vol. 35, pp. 475–501, 1964. [8] G. J. Foschini and M. J. Gans, “On limits of wireless communications in a fading environment when using multiple antennas,” Wireless Personal Communications, vol. 6, pp. 311–335, 1998. [9] S. M. Alamouti, “A simple transmit diversity technique for wireless communications,” IEEE Journal on Select Areas in Communications, vol. 16, pp. 1451–1458, August 1998. [10] V. Tarokh, N. Seshadri, and A. R. Calderbank, “Spacetime codes for high data rate wireless communication: Performance criterion and code construction,” IEEE Transactions on Information Theory, vol. 44, pp. 744–765, March 1998. [11] V. Tarokh, H. Jafarkhani, and A. R. Calderbank, “Spacetime block codes from orthogonal designs,” IEEE Transactions on Information Theory, vol. 45, pp. 1456–1467, July 1999. [12] G. Ganesan and P. Stoica, “Spacetime block codes: A maximum snr approach,” IEEE Transactions on Information Theory, vol. 47, pp. 1650–1656, May 2001. [13] V. Tarokh, H. Jafarkhani, and A. R. Calderbank, “Spacetime block coding for wireless communications: performance results,” IEEE Journal on Select Areas in Communications, vol. 17, pp. 451–460, March 1999. [14] V. Tarokh, A. Naguib, N. Seshadri, and A. R. Calderbank, “Combined array processing and spacetime coding,” IEEE Transactions on Information Theory, vol. 45, pp. 1121–1128, May 1999. [15] G. D. Golden, G. J. Foschini, R. A. Valenzuela, and P. W. Wolniansky, “Simplified processing for high spectral efficiency wireless communication employing multi-element arrays,” Journal on Selected Areas in Communications, vol. 17, p. 18411852, November 1999. [16] B. Hassibi and B. M. Hochwald, “High-rate codes that are linear in space and time,” IEEE Transactions on Information Theory, vol. 48, pp. 1804–1824, July 2002. [17] L. Zheng and D. Tse, “Diversity and multiplexing: a fundamental tradeoff in multiple-antenna channels,” IEEE Transactions on Information Theory, vol. 49, pp. 1073–1096, May 2003. [18] H. Bolcskei, D. Gesbert, C. Papadias, and A. van der Veen, Space-Time Wireless Systems. Cambridge University Press, 2006.…

    • 7383 Words
    • 30 Pages
    Good Essays
  • Satisfactory Essays

    Ocdma

    • 439 Words
    • 2 Pages

    References: International Engineering Consortium. (2005). Annual review of wireless communications. Chicago, Ill: Professional Education International.…

    • 439 Words
    • 2 Pages
    Satisfactory Essays
  • Powerful Essays

    Cmos Lna Design Techniques

    • 2542 Words
    • 11 Pages

    Bagher Afshar, Ali M. Niknejad Berkeley Wireless Research Center, Dept. of EECS, UC Berkeley, Berkeley, CA 94704, USA…

    • 2542 Words
    • 11 Pages
    Powerful Essays
  • Good Essays

    Mobile Internet services with value-added QoS. This paper gives the reasons for the evolution of 4G, though 3G has not deployed completely. And then gives the information on the structure of the transceiver for 4G followed by the modulation techniques needed for the 4G. Later this gives the information about the 4G processing .Finally concludes with futuristic views for the…

    • 1836 Words
    • 8 Pages
    Good Essays