National Repository of Grey Literature 28 records found  previous11 - 20next  jump to record: Search took 0.01 seconds. 
Radio Watchdog
Matuška, Jan ; Heriban, Pavel (referee) ; Krček, Petr (advisor)
This thesis deals with a design and implementation monitoring system of Starhill society computer network. Part of the design is development and realization hardware modules that provide restarting of remote network devices. Command transmission is realized through discretionary transceivers available, whose regulations can make such transmissions possible. A usage of 466~MHz frequency band is the main assumption. Both concept and implementation are described in the thesis. The designed system is integrated to the existing IS of the association.
HF and IF circuits of shortwave radiostation
Šnajdr, Václav ; Vágner, Petr (referee) ; Lukeš, Zbyněk (advisor)
The study, description, design and implementation of selected blocks of multiband shortwave radio station are dealt with in the thesis. Focus is placed on the concept of multiband shortwave radio stations, with an emphasis on high frequency and intermediate frequency circuits. The first chapter is devoted to description of the transceiver block diagram which is designed as superheterodyne. The design of bandpass input filters, intermediate frequency crystal filters and output filters is described. Simulation results and the measured characteristics of the implemented functional blocks are presented. Furthermore, the amplifier circuits which maintain impedance matching of individual blocks are discussed. SSB signal generation in the transmitter part of radio station and final stage power amplification are depicted.
Wireless Remote Controller for Linear Repeater
Veselý, Tomáš ; Šebesta, Jiří (referee) ; Rumánek, Jaroslav (advisor)
The project deals with the problems of the wireless remote control of the linear repeater. The implementation is devided into two function parts. The first part is a network focusing on the input of instructions by the user, processing of the information, displaying the actual setting and sending the information on the given instructions. The second part deals with processing of the given information from the first part and its discharging. Both parts are controlled by the microprocessors.
Software-defined radio OFDM frame generation according to IEEE 802.22
Honek, Marek ; Gazda, Juraj (referee) ; Maršálek, Roman (advisor)
Tato práce navrhuje nový radio komunikační standard AWRAN určený pro přístup k radioamatérké síťi HAMNET která nevyžaduje volný LOS k přístupovému bodu. Dále se práce popisuje prototypovou implementaci zjednodušených rámců tohoto standardu na SDR a testovací aparaturou, která je používána pro tyto účely. V první kapitole je představen standard IEEE 802.22 WRAN, ze kterého AWRAN vychází. Jsou popsány pojmy jako OFDM a OFDMA, výhody a způsoby jejich použití. Dále jsou zde popsány také modulační techniky PSK a QAM, kódování pro detekci a opravu chyb přenosu a zdroje těchto chyb. V druhé kapitole je zevrubný popis parametrů navrhovaného standardu AWRAN. Jsou popsány OFDM parametry, struktura rámců a superrámců. Je popsán způsob co-existence více buněk AWRAN a přesná podoba čtrnácti řídících zpráv, které umožňují efektivní rozdělení zdrojů přenosového pásma mezi až čtyři základnové stanice a až 63 uživatelů pripojených ke každé z těchto stanic. Třetí kapitola popisuje strukturu zjednodušeního rámce, který byl implementován na testovací aparatuře RPX-100. Popisuje i aparaturu samotnou a její základní stavební hardwarové prvky i softwarovou knihovnu, která byla pro implementaci zjednodušeného rámce použita. V této kapitole je popsán i připravený testovací spoj a teoretický výpočet útlumu tohoto spoje. Čtvrtá kapitola se zabývá programy, které byly v rámci této práce vytvořeny. Dva z nich sloužily pro první seznámení s hardwarem a softvarovými knihovnami. Další program slouží jako generátor dříve popsaných zjednodušených rámců, které následne odesílá za použití SDR. Ten stejný program slouží i jako příjmač těchto rámců. Poslední připravený program provádí simulaci bezdrátového přenosu pomocí matematického modelu kanálu. Dále počítá závislost BER na SNR u takto simulovaného přenosu. V poslední kapitole jsou vypsány funkce, které byly nadefinovány a použity v programech popsaných v předchozí kapitole.
Autonegotiation implementation for 25 - 100 Gbps Ethernet interfaces
Válek, Vladislav ; Jedlička, Petr (referee) ; Tomašov, Adrián (advisor)
This bachelor's thesis addresses the design of the auto-negotiation component for network interface cards controlled by FPGAs. Auto-negotiation function allows to advertise the available communication parameters, like the link speed, the transmission pause ability or Forward Error Correction (FEC) ability, by either side of the common link and determine the common abilities, which will be used to establish a connection. In the beginning, the internal parts of Xilinx UltraScale+ FPGA family are introduced with greater emphasis on the description of GTY transceivers. In the next chapter are introduced the mechanisms of auto-negotiation function as described in clause 73 of the IEEE 802.3-2018 standard. The design here is created for Ethernet interfaces running at speed 25~Gbps and is written in VHDL language. The next chapter describes the necessary steps which are required for the implementation on the FPGAs, where high-speed transceivers are in use. Function of the created design was then checked within a simulation and the correspondent results are also provided in this thesis. In the end, the testing of the designed auto-negotiation component took place for which the network card with Vitex 7 UltraScale+ FPGA was used. The testing process includes the use of the Integrated Logic Analyzer (ILA) which was inserted into final design. The achieved results from testing of both, the auto-negotiation process and surrounding physical layer processes, are described here with proper commentary.
Bluetooth® Low Energy Vehicle Keyless Entry
Šterc, Filip ; Povalač, Aleš (referee) ; Frýza, Tomáš (advisor)
Tato práce se zabývá návrhem demonstračního kitu bezlíčového přístupu pro vozidla s využitím nejnovějších integrovaných obvodů Bluetooth Low Energy a budičů automobilové sběrnice od společnosti ON Semiconductor. Aplikace umožňuje ruční i automatické odemykání dveří vozidla ze vzdáleného klíče realizovaného chytrým telefonem. Řešení se zabývá detekcí vzdálenosti vzdáleného klíče, bezpečností BLE spojení a komunikací přes automobilovou sběrnici LIN mezi moduly demonstračního kitu.
Automatic Antenna Tuner
Šváb, Jaroslav ; Lukeš, Zbyněk (referee) ; Šebesta, Jiří (advisor)
This degree work deals with the design and implementation of an automatic antenna tuner for short-wave transmitters. The device works within the short-wave range in (1.5 MHz - 30 MHz) band according to the selection of the given frequency. Its principle is that the tuner has a small range of adapted impedances, but it is usually sufficient for fine tuning of most deviations in the system of antenna 50 - feeder 50 - transceiver outlet 50 . It is also equipped with memories which the settings for the individual bands or frequency segments are stored into. Then the transition from one band to another is quick, easy and, first of all, safe, which is a great advantage. In automatic mode, a SWR limit from which the tuner should start to tune can be set. Interconnection with a TRX is not necessary in a fully automatic mode, the device tunes automatically after keying if the set limit of SWR has been exceeded. The automatic tuning is very quick with this device, if the antenna being tuned is not stored in the memory the tuning lasts ca 0.5 - 6 s, if the tuner uses the memory. It could be said that the work with the tuner is without problems, it is possible to learn to control it in a short time. The tuner is small and light. The result of the whole project is a compact device controlled by the user by means of push buttons.
FITkit as a Remote Controller Transceiver
Růžek, Michal ; Strnadel, Josef (referee) ; Vašíček, Zdeněk (advisor)
The bachelor's thesis is about communication protocols used in infrared remote controls of consumer electronics. It describes widely used protocols such as RC5, NEC and SIRC, their properities and methods of decoding. Transceivers are realized via components inside FITkit's FPGA chip, using simple HW module. Demo application written in C language is also included.
Miniaturization and Range Extension of W-DMX v1.0 Module
Rojček, Martin ; Jaroš, Jiří (referee) ; Šimek, Václav (advisor)
The aim of this master thesis is to design a wireless system which would be primarily used for a control of stage lighting. Our idea is to establish wireless links, that will carry DMX512 protocol, between individual lighting devices based on wireless transceiver nRF2401A. The foundation of our project comes from a previous design, which was not completely suitable for a practical use because of its rather large proportions and a short RF range. The project resolves the issue of relatively short range coverage through the deployment of RF amplifier RF5722. In the same tme, it also takes into account other technical aspects such as the use of antenas with a higher gain, front-end circuits or increased transmission reliability through frequency hopping scheme. Proper attention is also given to a minimalization of the module dimensions by using SMD components and layout adjustements, so it would be possible to place the whole board inside XLR connector. Set of printed circuit boards with the specified characteristics, which is the expected outcome of our project, were designed with Eagle PCB design environment.
Wireless security facility
Gargulák, Lukáš ; Morský, Ondřej (referee) ; Zeman, Václav (advisor)
The content of this thesis is the design, construction and programming of wireless security device. This wireless security system consists of two units. Personal unit and sensor unit. This thesis compares two ISM bands 433 MHz and 868 MHz. The thesis presents a selection of parts for construction wireless security device. The work also deals with the structure of transmitted frames on the link layer. Marginally are discussed ways to reduce consuption AtmelAVR microcontrollers and also two ways of charging Li-Ion battery. It also outlined the firmware of both units. Its complete source code is included on the DVD.

National Repository of Grey Literature : 28 records found   previous11 - 20next  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.