Results 241 to 250 of about 381,897 (285)

Estimator structures in a fast time-variant channel

Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324), 2003
In an earlier paper some novel linear LS and MMSE estimators were presented, able to estimate a fast time-variant channel. The estimators can also be applied in the quadratic estimator-correlator receiver. In this paper some block diagrams of the estimators are presented, including a matched filter bank, a sampler, a time-variant equalizer and a ...
Perälä, Eija, Mämmelä, Aarne
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Measurements on time-variant communication channels

IEEE Transactions on Information Theory, 1962
We discuss the problems of making detailed measurements of instantaneous values and the statistical parameters of time-variant filters when observations are permitted at the filter terminals only. It appears that the product of the maximum time- and frequency-spreadings produced by the time-variant filter sets a limit on our ability to determine the ...
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Modeling time-variant multipath characteristics for MIMO channels

2008 IEEE Antennas and Propagation Society International Symposium, 2008
This paper has demonstrated the implementation of a time-variant multipath channel model for MIMO applications. The model formulation uses measured channel data to determine the statistical representation of the time-variant multipath cluster characteristics followed by an AR model generation of stochastic realizations of the MIMO channel matrix as a ...
null Chan Chen, M.A. Jensen
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Identification of time-variant directional mobile radio channels

IEEE Transactions on Instrumentation and Measurement, 2000
For the identification of the time-variant, directional structure of the mobile radio channel impulse response (CIR), a broadband vector channel sounder is described. The measurement procedure relies on periodic multifrequency excitation signals, correlation processing, and joint delay-azimuth super-resolution based on the two-dimensional (2-D) unitary
R.S. Thoma, D. Hampicke, A. Richter, G. Sommerkorn, A. Schneider, U. Trautwein, W. Wirnitzer   +6 more
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OFDM transmission over time-variant multipath channels

International Broadcasting Convention - IBC '94, 1994
The paper addresses the influence of multipath propagation on the transmission of OFDM (orthogonal frequency division multiplexing) modulated radio signals. The author derives a discrete-time channel model for the WSSUS (wide-sense stationary uncorrelated scattering) channel.
openaire   +1 more source

Cluster parameters for time-variant MIMO channel models

2nd European Conference on Antennas and Propagation (EuCAP 2007), 2007
The next challenge for MIMO radio channel models is to simulate the time-variant nature of the channel correctly. Cluster-based MIMO channel models are well suited for this problem, however they currently lack an accurate parameterization of the time-variant cluster parameters.
N. Czink, R. Tian, S. Wyne, G. Eriksson, T. Zemen, J. Ylitalo, F. Tufvesson, A.F. Molisch   +7 more
openaire   +1 more source

Iterative Versus Adaptive Equalizers in Time-Variant Channels

GLOBECOM 2009 - 2009 IEEE Global Telecommunications Conference, 2009
This paper discusses the application of iterative versus adaptive equalizers to a Universal Mobile Telecommunications System (UMTS) High Speed Downlink Packet Access (HSDPA) receiver. Among the investigated algorithms are the Least Mean Square (LMS) and Recursive Least Square (RLS) algorithms and their adaptions to Code Division Multiple Access (CDMA),
Clemens Buchacher, Joachim Wehinger, Mario Huemer   +2 more
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Measurement of random time-variant linear channels

IEEE Transactions on Information Theory, 1969
This paper concerns the problems of the measurability and measurement of random time-variant linear channels. With regard to measurability, a new, less stringent channel measurability criterion is proposed to supersede the BL product introduced by Kailath. This criterion involves the area of occupancy of the Doppler-delay spread function (or its dual).
openaire   +1 more source

A new approach to tracking time-variant channels

The 5th International Symposium on Wireless Personal Multimedia Communications, 2003
This paper presents a method for joint channel and data estimation for transmission over frequency-selective and time-variant channels. Hereby, fast time-variant channels can be tracked, which is important for mobile communications at high velocities.
S. Gligorevic, U. Sorger
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Effects of Time Variant Channel on a Time Reversal UWB System

GLOBECOM 2009 - 2009 IEEE Global Telecommunications Conference, 2009
Time reversal (TR) is gaining more and more attention due to its potential to simplify the receiver for an ultra-wideband communication system. The temporal and spatial focusing properties of a TR communication system allow the detection of the received signal with simple receivers. However, the transmitter system becomes complicated as perfect channel
Naqvi, Ijaz Haider, Besnier, Philippe, El Zein, Ghaïs   +2 more
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