On Synchronization in OFDM Systems Using the Cyclic Prefix
نویسندگان
چکیده
In this paper, we present a data-based method for simultaneous Maximum Likelihood (ML) symbol timing and carrier-frequency offset estimation in Orthogonal frequency-division multiplexing (OFDM) systems. The cyclic extension, a guardspace preceding OFDM frames, is of decisive importance for this method. It is shown that the redundancy introduced by this cyclic extension allows the estimation to be performed without additional pilots. Simulations show that the performance of the frequency estimator is usable in a tracking mode while the timing estimation can be used in an acquisition mode.
منابع مشابه
Algorithms and applications of channel impulse response length estimation for MIMO-OFDM
The performance of the widely applied timedomain channel estimation for SISOand MIMO-OFDM systems strongly depends on the preciseness of information regarding maximum channel impulse response (CIR) length. In practice the required CIR length is usually approximated by the length of the cyclic prefix which is an upper bound for most of the actual instantaneous CIR length. In this article, we int...
متن کاملSynchronization for Ofdm-based Communication System: a Brief Overview
The goal of current paper is to provide an overview of all synchronization tasks to be performed in orthogonal frequency – division multiplexing (OFDM) based communication system. Symbol timing and frequency synchronization solutions in systems with cyclic prefix (CP) are described. Basic channel estimation and equalization based on pilot tones is described and simulation results presented. Alt...
متن کاملStudy of Timing Synchronization in MIMO-OFDM Systems Using DVB-T
OFDM (Orthogonal Frequency Division Multiplexing)provides the promising physical layer for 4G and 3GPP LTE Systems in terms of efficient use of bandwidth and data rates. This paper highlights the implementation of OFDM in Digital Video Broadcasting-Terrestrial (DVB-T). It mainly focuses on the timing offset problem present in OFDM systems and its proposed solution using Cyclic Prefix (CP) as a ...
متن کاملEffect of the cyclic prefix on the timing synchronization method in ACO-OFDM systems
Recently, a new timing synchronization method for optical wireless systems using asymmetrically clipped optical OFDM (ACO-OFDM) has been proposed. The synchronization method makes use of a novel training symbol and its autocorrelation properties for timing offset estimation via a timing metric. In this paper, we will discuss the effect of the length of cyclic prefix (CP) on the detection of the...
متن کاملML Estimation of Initial Symbol Timing and Frequency Offset in OFDM Systems
In this paper, we present a simple and efficient novel joint synchronization algorithm for OFDM system. It is based on training cyclic prefix to estimate the Initial symbol timing and carrier frequency offsets. Training sequence is an important part of the symbols which organize the frame timing and initial symbol timing. Cyclic prefix used the circular property for insertion and removal itself...
متن کاملChannel Effect Compensation in OFDM System under Short CP Length Using Adaptive Filter in Wavelet Transform Domain
Channel estimation in communication systems is one of the most important issues that can reduce the error rate of sending and receiving information as much as possible. In this regard, estimation of OFDM-based wireless channels using known sub-carriers as pilot is of particular importance in frequency domain. In this paper, channel estimation under short cyclic prefix (CP) in OFDM system is con...
متن کامل