Ralf Heddergott

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This paper describes a model for mobile radio channels that includes consideration of directions of arrival and is thus suitable for simulations of the performance of wireless systems that use smart antennas. The model is specified for 13 different types of environments, covering macromicroand picocells. In this paper, a hierarchy of modeling concepts is(More)
A stochastic radio channel model (SRCM) for broadband indoor mobile systems operating at 5.2 and 17 GHz has been derived within the ACTS project AC085 Magic WAND. The SRCM was designed to accurately describe the time, frequency, direction, and polarization dispersive characteristic of real radio channels because these effects are important for the design of(More)
|A demodulation algorithm for a base station receiver in a direct sequence (DS) spread spectrum code division multiple access (CDMA) communication system is proposed which performs joint multiuser detection and estimation using the output signals of an antenna array in the absence of a tight power control. The scheme is a combination of a multistage (MS)(More)
This document describes a general proposal for combining all relevant effects of the directional mobile radio channel. Effects included are pathloss, shadowing, small-scale fading due to interference, joint delay and azimuth spreading. The latter accounts for the clustering nature of the channel when observed with wideband and/or directionally resolving(More)
A novel wideband channel sounding system operating at 24 GHz with an RF bandwidth of 1 GHz is presented. The SAGE (spacealternating generalized expectation maximization) algorithm is used for obtaining high-resolution estimates of the parameters characterizing the impinging waves, i.e. the delays, incidence azimuths, incidence elevations and complex(More)
This paper summarizes the achievements of Subworkinggroup 2.1 (SWG2.1) of the COST259 initiative. A common approach for modelling the time-variant wideband angular-dispersive radio channel for link-level simulations is derived and the main parameters are described. The basic modelling philosophy is a stochastic signal description where deterministic(More)
A wideband indoor channel sounder operating at 24 GHz with a delay resolution of 2 ns and an estimation scheme based on the space-alternating generalized expectation-maximization (SAGE) algorithm is used for obtaining high resolution estimates of the parameters characterizing the impinging waves, i. e. their propagation delay, incidence azimuth, incidence(More)