The radio channel places fundamental limitations on the performance of mobile ad hoc wireless networks. In the mobile radio environment, fading due to multipath delay spread impairs received signals. The purpose of this thesis is to develop a radio channel model and examine the effect of various parameters on channel behavior that is representative of environments in which mobile ad hoc wireles...

In this paper the performance of the MMSE-based equalization receivers under overloading conditions is analyzed, for SISO (Single Input, Single Output) and MISO (Multiple Input, Single Output) antenna arrangements. Both random and orthogonal spreading sequences are analyzed, for the main UMTS (Universal Mobile Telecommunications System) TDL (Tapped Delay Line) channel models, namely Pedestrian ...

We investigate the performance of uncoded uplink transmissions in a broadband code division multiple access (CDMA) system using a tapped delay line (TDL) antenna array. First, the weights of a TDL antenna array are derived for broadband CDMA. Using these weights, we perform simulations to demonstration how TDL antenna arrays can help reduce multi-access interference (MAI), allow the use of spre...

This paper analyzes performances of the Pulse Interval Modulation (PIM) scheme for impulse radio ultra-wideband (IR-UWB) communication systems. Due to the PIM anisochronous nature, a tap delay line (TDL) coded division multiple access (CDMA) scheme based on strict optical orthogonal codes (SOOC) is proposed. This scheme is suitable for multiuser high-speed data asynchronous transmission applica...

Radio access technologies (RATs) are a key topic in railways, enabling them better service rendering terms of shorter headways between trains, higher safety levels and customer satisfaction. Very often, these railway RATs need lot time to be developed, tested put into service, which implies lack efficiency bottlenecks the evolution systems. To solve this situation, an emulation platform that co...

This paper deals with the definition and the implementation of a Wideband Directional Channel Model (WDCM) based on the COST 259 recommendations. Cluster of replicas are introduced by means of Tapped Delay Line (TDL). Macro, Micro and Pico cells models are considered in different general radio environments. Proposed channel model can be used in a Link Level Simulator (LLS). A good compromise be...

Techniques for modeling and simulating the underlying channel-PHY play an essential role in understanding network protocol and application behavior of tactical data link (TDL). Inappropriate modeling and simulation of channel-PHY make the results incredibility. In this paper a model architecture of channel and physical layer is described in NS-2 (Network Simulator version 2). The five key techn...

Many communication, control, and information processing subsystems (such as data equalizer, array processor, whitening filter, dynamical system identifier, etc.) are modeled by linear systems incorporating tapped delay lines (TDL). Such optimized subsystems result in full precision multiplications in the TDL. In order to reduce complexity and cost in a microprocessor implementation, these multi...

Two different partially recurrent neural networks st,ructured as Multi Layer Perceptrons (MLP) are inves tigated for time domain identification of a nonlinear structure. The one partially recurrent neural network has feedback of a displacement component from t,he output layer to a tapped-delay-line (TDL) input layer. The other recurrent neural network bazd on the Innovation State Space model (I...