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In this thesis some different modulation schemes for xDSL-techniques are compared. The investigated techniques are ADSL, G.lite, ADSL2, HDSL, SHDSL and VDSL. The modulation methods used are DMT, CAP and different versions of PAM. Several broadband techniques also use Trellis …
En VHDL-implementation av algoritmer för att modulera & demodulera SOQPSK-signaler
… miljö man har tänkt att använda trådlös kommunikation behöver man hitta en modulationsteknik som passar under rådande förhållanden. I början på 1980-talet utvecklade den Amerikanska militären en modulationsteknik som kallas för Shaped BPSK (SBPSK) avsedd att tillämpas i …
… VSC (Voltage Source Converter) that uses a technique called PWM (Pulse Width Modulation). There are a lot of PWM patterns that have been examined, but not in the field of power transmission where ABB Power Systems is working. The different PWM patterns can be used for reducing …
… and an acceptable coderate. The unequal error protection lies in the modulation scheme. By using knowledge of the weight distribution and the error correcting capability of the ternary code the signal points in the modulation scheme can be optimized in the sense of error …
en studie av bildkvalitet inom medicinsk <br /> röntgendiagnostik: en matematisk metod för jämförelse <br /> mellan olika röntgenapparater<br />
… det avbildande systemet. Detta görs lämpligen genom att bestämma systemets Modulation Transfer Function, MTF, eller ännu hellre Optical Transfer Function, OTF. MTF är en metod där amplituderna för varje frekvens i ingående och utgående bild jämförs. I OTF jämförs både amplituder …
At the Department of Technology and Built environment at the University of Gävle there was an interest to study GNU Radio, which is an "open source radio project. The project is based on that most of the radio signal processing is made in an ordinary PC. The idea behind this …
… information between acoustic waves and radio waves, but also various types of modulation, such as amplitude and frequency modulation is required.
Framtida konsumtion, export, import och produktion samt konsumtion under inverkan av ett klimatavtal
… paper reports on the future use of natural gas in Australia, depending on a modulation of consumption, export, import and total production until the year of 2020. These predictions are based on fitting curves to historical data. Further, the consumption of natural gas, coal and …
… can modulate the marine ecotoxicity of ionisable organic compounds. This modulation is seemingly dependent on the acidic or basic properties of a substance. In some cases there were uncertainties as to whether an increased toxicity was a result of an increased sensitivity of the …
… 54 Mbps. 802.11a uses Orthogonal Frequency Division Multiplexing (OFDM) where modulation is performed by an IFFT and the demodulation by an FFT. After modeling the FFT in Matlab and C, the FFT implementation has been validated using a soft microprocessor core by Xilinx …
sjukgymnastiska och närliggande behandlingsmetoder - en litteraturstudie
… been unknown but recent studies has shown that disturbance in the central pain modulation may be the cause. The aim of the study was to examine what kind of physiotherapy and close related treatment methods in the treatment of fibromyalgia there are and to determine their …
… communication systems are described including source coding, channel coding, modulation techniques as well as different techniques for spread spectrum. The fundamental principle for all spread spectrum systems is to use more bandwidth than necessary to spread the signal energy …
Störningar kan och kommer alltid att finnas på elnätet. Men de störningar som vissa hushåll fått uppleva efter det att den automatiska avläsningen sattes igång är inget som är normalt. Flimret som uppkommer i lampor på grund av störningen är mycket tydligt och det verkar även …
… for surveillance systems and measurement data collection. The modules use FSK modulation and a protocol developed by us. It has been shown that the protocol supports multiple senders. A complete system was demonstrated at the Technical Exhibition in Stockholm, at this year prize …
… or in music tones and scales ” to move between them by sudden or leading modulations, from the diatonic scales with alternative formations, to the symmetric spheres, to the melodic pentatonic scales and other alternative new formations, using plateauic solutions or chords in …
