Serwis Infona wykorzystuje pliki cookies (ciasteczka). Są to wartości tekstowe, zapamiętywane przez przeglądarkę na urządzeniu użytkownika. Nasz serwis ma dostęp do tych wartości oraz wykorzystuje je do zapamiętania danych dotyczących użytkownika, takich jak np. ustawienia (typu widok ekranu, wybór języka interfejsu), zapamiętanie zalogowania. Korzystanie z serwisu Infona oznacza zgodę na zapis informacji i ich wykorzystanie dla celów korzytania z serwisu. Więcej informacji można znaleźć w Polityce prywatności oraz Regulaminie serwisu. Zamknięcie tego okienka potwierdza zapoznanie się z informacją o plikach cookies, akceptację polityki prywatności i regulaminu oraz sposobu wykorzystywania plików cookies w serwisie. Możesz zmienić ustawienia obsługi cookies w swojej przeglądarce.
A new concept has been developed which can view vast regions of the Earth's surface. Ground HF transmissions are reflected by the ionosphere to illuminate the ocean over a few thousand kilometers. HF receivers detect the radio waves scattered by the sea and land surface. Using the theory of radio wave scatter from ocean surfaces, the HF data is then processed to yield the directional wave-height spectrum...
Wireless communication technology is spreading rapidly to all areas of our lives. The technology, which has a wide range of applications from radios, intelligent home systems, automation applications to GPS units, was used in monitoring the workers working in mines in this study. Most of the mining area underground mining is risky and the possibility of accident (gas jams, the explosion and dents,...
Compared to conventional radar systems, passive coherent location (PCL) systems utilize transmitters already deployed within an environment. In this paper, we investigate PCL systems to estimate an unknown target position in three dimensional space, and propose a target-tracking process of three steps: 1) receiver selection, 2) target-tracking algorithm, and 3) filtering process. To reduce an estimation...
Traditional cryptographic secret key establishment mechanisms are facing challenges with the fast growth of high-performance computing, and can be very costly in many settings, e.g. in wireless ad-hoc networks, since they consume scarce resources such as bandwidth and battery power. As an alternative, link-signature-based (LSB) secret key extraction techniques have received many interests in recent...
Vehicle-to-vehicle channel characteristics differ significantly from those of conventional cellular channels, especially in terms of fading statistics due to varying environmental conditions, link types, vehicle types, and objects that result in complex propagation effects. Accurate modeling of the vehicular channel remains a complex challenge. In this paper, existing, common vehicular channel models...
RF technology is widely used in many fields. This study is based on the knowledge of RF circuit. It is aimed to design a wireless communication transceiver, which includes transmitter circuit, receiver circuit and communication antenna. In design process, we do not only consider the transmitter circuit and the receiver circuit indicators to meet the requirements of the module, but also ensure that...
Scientific proposals of indoor positioning and range measurement are reviewed, with a discussion of their advantages and disadvantages. The considered technologies are: Radio Frequency, Ultrasonic, Camera-based solution, and Infrared. The typical constraints in indoor environments are high accuracy, low latency, low dimensions, and low energy dissipation.
The feasibility of asteroid detection using the Forward Scatter Radar Network that exploits three pulsars as transmitters is examined. We provide a power budget estimate for asteroid detection using such a FSR-network with the radio telescope used as a receiver. The numerical results are obtained for two known radio telescopes in the Netherland and three known pulsars.
Ultra-wideband (UWB) impulse radio is a technology ideally suited for centimeter-level localization, and especially attractive because of the possibility to employ backscattering tags which can be made energy autonomous. Still, achieving such accuracy in localizing backscattering tags is challenging and requires careful consideration in implementing the signal processing chain. This paper presents...
Low-Frequency (LF) Magneto-Inductive (MI) communication, used in LF Radio-Frequency Identification (RFID) systems, is very well suited for indoor positioning applications since LF magnetic fields are not greatly affected by the environment. However, LF magnetic fields may be distorted by ferromagnetic objects or get affected by LF Electromagnetic Interferences (EMI), which affects the accuracy and...
A worst-case model of spurious resonances which can occur in electromagnetic system consisting of an antenna, cable and transmitter output filter (or receiver input filter) is proposed. These resonances may cause significant increase in power of spurious emissions for transmitting equipment and the decrease in out-of-band radiated susceptibility levels for receiving equipment. Three amplitude-frequency...
The problem of a signal source or a signal receiver localization from time difference of arrival (TDOA) measurements is a crucial issue in many applications appearing in the fields of navigation, surveillance or wireless communication. In this paper we present the algorithm for finding a mutual location of both sources and receivers when the position of none of them is known. We derive an inequality...
Time difference of arrival (TDOA) is one of transmitter tracking method to find location or position based on the difference of arrival signals from transmitter to receiver in time domain. This work aims to find the position of a transmitter using TDOA method. Operating frequency used is amateur radio 144.100 MHz for sending and receiving burst signal. Time difference is calculated by using cross...
The development of telecommunications system in modern technology is increasing widely so that the process can take place more quickly and efficiently, one of which was the use of Software Defined Radio (SDR). SDR is a radio communication system where the components that have been typically implemented in hardware (mixers, filters, amplifiers, modulators/demodulators, detectors, etc.) are instead...
In this paper, sub-ionospheric Very Low Frequency/Low Frequency (VLF/LF) radio signals over the North Atlantic zone and North Pacific zone have been analysed during the major Sudden Stratospheric Warming (SSW) event of January, 2009. Signals from the transmitters like, NAA (24.0 kHz) and NKR (37.5 kHz) received at Germany and signals from the transmitters like, NLK (24.8 kHz) and NPM (21.4 kHz) received...
This work aims at understanding and evaluating the impact of using different path loss models in the optimization trade-off of small cell (SC) networks. In LTE-A, the more realistic propagation models are the more efficient the radio and network optimization becomes. In this work we compare four urban path loss models: the urban/vehicular and pedestrian test environment from the ITU-R M. 1255 Report...
In this paper, a full-duplex (FD) amplify-and-forward (AF) transmitter cooperative communication scheme is proposed for multiple access channel (MAC). In particular, two FD transmitters simultaneously transmit information to a common receiver and help each other's transmissions with the AF relaying scheme. By considering the accumulation of the residual self-interference and additive noise (RIAN)...
This paper analyzes and evaluates joint effect of primary interference and artificial noise on information securing capability of cognitive radio networks (CRNs) under interference power constraint, peak transmit power constraint, and Rayleigh fading. An exact formula for an important security performance metric, secrecy outage probability, is first derived and then validated by computer simulations...
Nanotechnology becomes reality paving the way for many new applications. In nanonetwork system, each nanosized device is equipped with limited capabilities and is dedicated to a basic task but the combination of the numerous devices actions results in high-level functions. In this context, large number of devices concentrated in a limited area must exchange data using wireless links. Spread in Time...
The paper presents a new method for estimating capacity of real communication channel in the absence of noise when PSK-n signals are used under conditions of strong intersymbol distortion caused by transient processes in selective systems of a linear radio path. The presented method has high accuracy and low computational complexity, which does not depend on the number of discrete states of the PSK-n...
Podaj zakres dat dla filtrowania wyświetlonych wyników. Możesz podać datę początkową, końcową lub obie daty. Daty możesz wpisać ręcznie lub wybrać za pomocą kalendarza.