Countable projective limits of countable inductive limits, so-called PLB-spaces, of weighted Banach spaces of continuous functions have recently been investigated by Agethen, Bierstedt and Bonet, who analyzed locally convex properties in terms of the defining double sequence of weights. We complement their results by considering a defining sequence which is the product of two single sequences. ...

This paper presents a simulation study of a smart antenna (SA) system based on direction-of-arrival (DOA) estimation is based on the MUltiple SIgnal Classification (MUSIC) algorithm for finding the Position Location (PL) of the desired user. The beamformer steer the main beam towards the desired user and nullify all other interferer, through adaptive beamforming using Least Mean Square (LMS) al...

Electron tube amplifiers may make use of either radio-frequency amplification or audio-frequency amplification, or both. Radio-frequency amplification consists in the amplification of the received radio-frequency current before it is detected. The use of radio-frequency amplification makes it possible to receive a very weak signal which can not be heard at all if only audio-frequency amplificat...

M ost readers will be broadly familiar with the concept of a radio direction finder (RDF). A basic RDF consists of a receiver and an antenna which can be rotated on its own axis. The direction of the transmitter is found by rotating the antenna for a signal peak or null. You can easily demonstrate the effect for yourself using a portable transistor radio fitted with a ferrite rod antenna. By tu...

This paper is concerned with the relay and jammers selection in two-way cooperative networks to improve their physical layer security. Three different categories of selection schemes are proposed which are; selection schemes without jamming, selection schemes with conventional jamming and selection schemes with controlled jamming. The selection process is analyzed for two different network mode...

In this study, we present two novel fusion approaches to merge subword and word based retrieval methods within a multilingual spoken document retrieval (SDR) system. Considering the fact that more than 6000 languages are spoken in the world today, resources (e.g., text and audio data, pronunciation lexicon) needed to develop Automatic Speech Recognition (ASR) systems for such a range of languag...

Diversely polarized antenna arrays are widely used in RF applications. The diverrity of rerponse provided b y such arrays can greatly improve direction finding performance over arrays sensitive to only one polarixation component. For d emitterr, direct implementation of a multidimensional estimation algorithm (e.g., maximum likelihood) requires a search f o r 3d parameters: d directions of arri...

High-frequency (HF) radars based on ground-wave propagation are used for remotely sensing ocean surface currents and gravity waves. For some 20 years a number of sytems have been developed taking advantage of improved electronics and computer techniques. However, the performance of these systems are limited by physical constraints, which are due to HF wave propagation and scattering as well as ...