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Pilot Symbols (pilot + symbol)

Distribution by Scientific Domains

Engineering	100%

Selected Abstracts

On the effects of interpolator window shape and symbol location on the BER of diversity PSAM 16-QAM

EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 4 2007
Lingzhi Cao
We consider pilot symbol assisted modulation (PSAM) implemented with a sinc interpolator. The sensitivity of the error rate performance to different window functions applied to the sinc interpolator is investigated. The bit error rates (BERs) for diversity M -ary quadrature amplitude modulation (MQAM) with different window functions applied to the sinc interpolator are compared. The Kaiser window is found superior to the other windows considered. A thorough discussion of the dependency of the BER performance on the symbol location is also given. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Iterative channel estimation and data detection in frequency-selective fading MIMO channels,

EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 5 2004
Maja Lon
Signals transmitted through multiple-input multiple-output (MIMO) wireless channels suffer from multiple-access interference (MAI), multipath propagation and additive noise. Iterative multiuser receiver algorithms mitigate these signal impairments, while offering a good tradeoff between performance and complexity. The receiver presented in this paper performs channel estimation, multiuser detection and decoding in an iterative manner. The estimation of the frequency selective, block-fading channel is initiated with the pilot symbols. In subsequent iterations, soft decisions of all the data symbols are used in an appropriate way to improve the channel estimates. This approach leads to significant improvement of the overall receiver performance, compared to other schemes. The bit-error-rate (BER) performance of the receiver is evaluated by simulations for different parameter setups. Copyright © 2004 AEI. [source]

A Hybrid Interference Cancellation Scheme for Multiuser Systems in Multipath Fading Channels

EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 2 2000
Ann-Louise Johansson
A new hybrid interference cancellation (IC) scheme is proposed for the uplink of multirate direct-sequence code division multiple access (DS-CDMA) systems communicating over mobile radio channels. The hybrid IC scheme includes both non-decision directed and decision directed IC, together with a modified RAKE combiner to utilize the diversity in a frequency-selective channel. The performance is evaluated via computer simulations for the two multiple data rate schemes, mixed modulation and multicode, in a multipath environment. Both known channel parameters and channel estimation using pilot symbols are considered. The results show that rnulticode or a combination of multicode and mixed modulation are preferable when handling multirate system and the loss in performance compared to the single-user bound is small. [source]

A low complexity partially adaptive CDMA receiver for downlink mobile satellite communications

INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 1 2003
Gau-Joe Lin
Abstract A novel CDMA receiver with enhanced interference suppression is proposed for pilot symbols assisted mobile satellite systems in the presence of frequency offset. The design of the receiver involves the following procedure. First, adaptive correlators are constructed at different fingers, based on the scheme of generalized sidelobe canceller (GSC), to collect the multipath signals and suppress multi-access interference (MAI). In particular, a partially adaptive (PA) realization of the GSC correlators is proposed based on the Krylov subspace technique, leading to an efficient algorithm without the need of complicated matrix computations. Second, pilot symbols assisted frequency offset estimation, channel estimation and RAKE combining give the estimate of signal symbols. Finally, further performance enhancement is achieved by an iterative scheme in which the signal is reconstructed and subtracted from the GSC correlators input, leading to faster convergence of the receiver. The proposed low complexity PA receiver is suitable or the downlink of mobile satellite CDMA systems, and shown to outperform the conventional fully adaptive MMSE receiver by using a small number of pilot symbols. Copyright © 2003 John Wiley & Sons, Ltd. [source]