A simplified MAP channel estimator for OFDM systems under Rayleigh fading

Date

2010-06-01

Author

ÇÜRÜK, SELVA
Tanık, Yalçın

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

283
views

0
downloads

This paper presents a simplified Maximum A Posteriori (SMAP) channel estimator to be used in orthogonal frequency division multiplexing (OFDM) systems under the Rayleigh fading assumption for the subchannels, using a parametric correlation model and assuming that the channel is frequency selective and slowly time varying. Expressions for the mean-square error (MSE) of estimations are derived to evaluate the performance of the estimator. The relation between the correlation of subchannels taps and error variance is investigated. Dependencies of the proposed estimator's performance on the correlation parameter estimation error and signal-to-noise ratios (SNR) estimation error are analysed. We provide approximations on the estimator algorithms in order to make the estimator practical. The simulations done using measured channel data show that the proposed estimator with approximations operates satisfactorily with negligible loss in performance. Finally, we investigate the symbol error rate (SER) performance of an OFDM system using quadrature phase-shift keying (QPSK) modulation, based on channel estimation modes (a) training sequence (b) decision feedback and (c) pilot subcarriers. The results have indicated that the proposed estimator performance is always better than maximum likelihood (ML) estimator, and as the subchannel correlation increases (large number of subcarriers) the performance comes very close to that of exactly known channel case. Copyright (C) 2010 John Wiley & Sons, Ltd.

Subject Keywords

Delay-spread, Error

URI

https://hdl.handle.net/11511/31834

Journal

EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS

DOI

https://doi.org/10.1002/ett.1415

Collections

Graduate School of Natural and Applied Sciences, Article

Suggestions

OpenMETU
Core

Simplified MAP estimator for OFDM systems under fading Cueruek, Selva Muratoglu; Tanık, Yalçın (2007-04-25) This paper presents a simplified Maximum A Posteriori (MAP) estimator, which yields channel taps in OFDM systems under fading conditions using a parametric correlation model, assuming that the channel is frequency selective, slowly time varying and Gaussian. Expressions for the variance of estimation error are derived to evaluate the performance of the MAP estimator. The relation between the correlation of subchannels taps and error variance and the effect of Signal to Noise Ratio (SNR) are investigated. Th...
A fine-resolution frequency estimator using an arbitrary number of DFT coefficients Orguner, Umut; Candan, Çağatay (2014-12-01) A method for the frequency estimation of complex exponential signals observed under additive white Gaussian noise is presented. Unlike competing methods based on relatively few Discrete Fourier Transform (DFT) samples, the presented technique can generate a frequency estimate by fusing the information from all DFT samples. The estimator is shown to follow the Cramer-Rao bound with a smaller signal-to-noise ratio (SNR) gap than the competing estimators at high SNR.
A Comparative Study on Non-Linear State Estimators Applied to Sensorless AC Drives: MRAS and Kalman Filter Akin, Bilal; Orguner, Umut; Ersak, Aydin; Ehsani, Mehrdad (2004-11-06) In this paper, two different nonlinear estimators applied to sensorless AC drives, Kalman Filtering techniques (EKF and UKF) and Model Reference Adaptive System (back emf ans reactive power models), are discussed and compared to each other. Both of the observer types are studied and analyzed both experimentally and theoretically. In order to compare the observers precisely, the observers are tested under the identical conditions.
A study on the discretization of fractional Brownian motion Coşkun, Buket; Vardar Acar, Ceren; Demirtaş, Hakan (2020-12-01) In this study, we first discretize the fractional Brownian motion in time and observe multivariate Gaussian random variables (mGrv) to have a fractional Gaussian noise (fGn). Afterwards, we have discretized this discrete time process in space using a discretization proportion p and observe a random walk. We carry out this simulation study to foresee whether the correlated random walk using certain discretization parameters p behave similar to fBm. Based on this simulation study, we conclude on two important...
An Efficient Numerical Approach for Evaluating Sommerfeld Integrals Arising in the Construction of Green's Functions for Layered Media Özgün, Özlem; Mittra, Raj; Kuzuoğlu, Mustafa (2022-01-01) This paper presents an efficient approach for evaluating the Sommerfeld integrals in the spectral domain, whose integrands typically show an oscillatory and slowly decaying behavior at high frequencies, e.g., in the millimeter wave regime. It is well known that these integrals arise in the representations of the dyadic Green's functions of layered media and efficient computation of these Green's functions is key to rapid CEM modeling of patch antennas and printed circuits designed for 5G appli...

Citation Formats

S. ÇÜRÜK and Y. Tanık, “A simplified MAP channel estimator for OFDM systems under Rayleigh fading,” EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, pp. 396–405, 2010, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31834.