In a multiple access communication system that uses packet transmissions, the packets of one user might be subject to asynchronous interference from the packets of other users in the system. This paper analyses the influence of the placement of training symbols on the performance of the channel

protocol. For such a network, a new class of high rate, trainingsymbol embedded (TSE) SSD DSTBCs are proposed from TSE-CODs. The constructed codes include the training symbols within the structure of the code which is shown to be the key point to obtain high rate along with the SSD property. TSE

We present an automatic approach to tree annotation in which basic nonterminal symbols are alternately split and merged to maximize the likelihood of a training treebank. Starting with a simple Xbar grammar, we learn a new grammar whose nonterminals are subsymbols of the original nonterminals

ABSTRACT In this paper, the problem of line-of-sight (LOS) direction of arrival (DoA) estimation in multipath channels is addressed. The system that we propose is based on the well-known cyclic prefixed (CP) orthogonal frequency division multiplexing (OFDM) scheme. The algorithm searches the time instant corresponding to the first arrival path (FAP), i.e., the LOS component that brings the DoA information. A time domain channel estimator evaluates the complex amplitude of the FAP. Finally, the FAP complex amplitude of each antenna is used to estimate the DoA with a low complexity single source method. Several numerical results validate the robustness of this algorithm, also in the case when the multipath components are superimposed to the LOS component.

This paper discusses the estimation and correction of large frequency offsets in the context of OFDM based WLANs such as BRAN HIPERLAN/2 and IEEE802.11a. Several algorithms with different complexity/performance trade-offs are proposed, all based on the exploitation of frequency domain properties of standard burst preambles: A correlation based approach leads to optimum performances at a moderately high cost while simple unit-or zero-carrier detection will lead to sub-optimum, but very low-cost implementation schemes. In the framework of the IST BROADWAY project1, this technique is used in order to keep compatibility to 5 GHz WLAN standards at a carrier frequency of 60 GHz where large frequency offsets occur. Simulation results prove that a 20 ppm offset at 60 GHz is detected at a high reliability.

We consider the problem of training symbol placement for timing acquisition in band-limited, baud-rate sampled systems with inter-symbol interference and frequency offset. The conventional approach is to place known symbols at the start of the transmitted packet and use these at the receiver to run

Abstract — A rapid synchronization method is presented for an orthogonal frequency-division multiplexing (OFDM) system using either a continuous transmission or a burst operation over a frequency-selective channel. The presence of a signal can be detected upon the receipt of just one training

We consider the problem of training symbol placement for timing acquisition in digital magnetic recording systems that can be modeled as band-limited, baud-rate sampled systems with intersymbol interference and frequency offset. The conventional approach is to place known symbols at the start

] and complexity advantage of [SI is proposed. Furthermore, we present the effects of the number of identical parts contained in the training symbol on the frequency offset estimation performance. Our results indicate that an improper choice of the number of identical parts contained in the training symbol can

This paper contains two algorithms proposed for synchronization in OFDM system. The first is having 1 symbol offset while calculating the timing metric, and the second is introduced in new parameter such as Reduction Factor(ρ), Break Constant(βk) and Implant Depth(δI) in order to control the power