In this paper we present a new channel delay spread estimator for OFDM based communication systems. The estimator operates in a wide range of channel delay spreads and mobile users velocities (0−360 km/h). The estimated value can be taken to select filters on the actual channel state, for instance two-dimensional (2D) Wiener filters. The estimator is based on a decision feedback signal, which i...

Waveguide analysis is used to predict power levels received in a microcellular system in an urban environment. An Urban street with tall buildings on both sides is modeled by a plate parallel waveguide made of rough plates. The distribution of power among the waveguide modes tends to concentrate in the low order modes, at large distances from the source antenna. The waveguide–based model predic...

Waveguide theory is suggested for the analysis of UHF radiation in urban microcellular environments, where both the transmitter and the receiver are below rooftop level. The delay profile is calculated from the steady state power distribution among the modes of the waveguide. The delay profile is very asymmetrical because most of the power is contained in the low order (faster) modes, and becau...

Abstract—This paper describes a non-blind technique, channel sounder, to characterize a wireless channel. This technique is based on the transmission of a pseudo random sequence through the channel, the calculation of its autocorrelation to estimate the channel impulse response, and from it the calculation of the Delay and Doppler spread parameters. This channel sounder was implemented using GN...

In a frequency-selective multiple-input multiple-output (MIMO) channel, the optimum transmission is achieved by beamforming with eigenvectors obtained at each discrete frequency point, i.e., an extension of eigenbeam-space division multiplexing (E-SDM). However, the calculation load of eigenvalue decomposition at the transmitter increases in proportion to the number of frequency points. In addi...