Measurements and modelling of rms delay spread (RDS) in indoor line-of-sight (LOS) conditions at HIPERLAN/U-NII frequencies (5.2GHz) with omni-directional antennas show that the maximum RDS in a room is dependent on the dimensions of the room and the reflection coefficient of the walls. Furthermore, in a given room RDS increases with distance from the transmitter up to a maximum value and plate...

Delay tracking of spread-spectrum signals is widely used for ranging in radio frequency based navigation. Its use in non-coherent optical ranging, however, has not been extensively studied since optical channels are less subject to narrowband interference situations where these techniques become more useful. In this work, an early-late delay-locked loop adapted to indoor optical ranging is pres...

A mobile social network (MSN) is a special delay tolerant network (DTN) composed of mobile nodes with social characteristics. Mobile nodes in MSNs generally visit community homes frequently, while other locations are visited less frequently. We propose a novel zero-knowledge MSN routing algorithm, homing spread (HS). The community homes have a higher priority to spread messages into the network...

The Volterra delay integral equations have numerous applications in various branches of science, including biology, ecology, physics and modeling of engineering and natural sciences. In many cases, it is difficult to obtain analytical solutions of these equations. So, numerical methods as an efficient approximation method for solving Volterra delay integral equations are of interest to many res...

The paper reports on the experiments undertaken at the University of Wollongong to characterise delay parameters of an indoor wireless channel at 5GHz bandwidth. The measurements were undertaken at different locations around the campus with results recorded for a post-processing to calculate mean excess delay, r.m.s. delay spread, and the coherence bandwidth of the channel.

In an urban environment, a multipath propagation is one of the basic phenomena affecting a quality of received signals. This causes dispersions in time and angular domains. Basic parameters describing these dispersions are the rms delay spread and rms angle spread, respectively. The delay spread is related to a frequency of the transmitted signal and the nature of the propagation environment. I...

Delay in the computation of the signal-to-interference ratio in communication systems is unavoidable. In the the case of mobile communication, delay is a very critical problem due the fast variation of the communication channel and the need for effective, fast and accurate power control. In this paper we present our approach to dealing with the delay in mobile communication systems as well as o...

1 This work was supported in part by an Australian Research Council grant Abstract Polynomial cancellation coded orthogonal frequency division multiplexing (PCC-OFDM) with overlapping symbol periods is a modulation scheme with properties that make it well suited to high speed data transmission including mobile applications. PCC-OFDM is much less sensitive to frequency offset and Doppler spread ...

The bit error rate (BER) performance of a pulse position modulation (PPM) scheme for non line-of-sight (LOS) indoor optical links employing channel equalization based on the artificial neural network (ANN) is reported in the paper. Channel equalization is achieved by training a multilayer perceptrons (MLP) ANN. A comparative study of the unequalized „soft‟ decision decoding and the „hard‟ decis...

Introduction: Multipath propagation characteristics for indoor radio channels has recently attracted tremendous attention. There have been attempts to study the statistics of the multipath spread and to model the indoor radio channel.’-5 The effects of short time variations in the delay spread and power, caused by human traffic around a transmitter and receiver, has not yet been thoroughly inve...