[en] Bridging the gap from theory to real-world, handson experience is an always present challenge in Education. The advent of computers allowed for simulation, a halfway step from theory into practice. In Telecommunications Engineering, Software Defined Radio allows students to design and test wireless equipment in real communication by means of a personal computer connected to a simple, low cost, generic radiofrequency device. The paradigm has changed the approach to wireless equipment and communications protocols design across industry and academia. In Education, it has succeeded in providing students with an experience very similar, if not equal, to what they will face in their professional lives. This approach resulted in a deeper understanding and better ability development than was possible through simulation, since several communication problems (such as those related to radiofrequency propagation are very difficult to model realistically. Moreover, this approach has proved to be strongly motivating for students, who design systems through a graphical interface by interconnecting blocks with specific functionality, but can later experience the results in real communications. This article describes our teaching experience and lessons learned with Software Defined Radio for Engineering Education. We used GNU Radio, an open and free software framework, complemented with GNU Wireless Network, an extension of our design to support data communications. The paradigm involved both graduate and undergraduate courses in Wireless Communication with strong lab content, undergraduate projects, early research training, and several master thesis. (Author)

[en] Master courses need to have a practical element, applying already known concepts to concrete problems. In this paper, the design and manufacturing of a radio link using APRS protocol over AX.25 will be presented as coursework during several lab sessions. The aim is to create a system that is able to poll data from several sensors and send them wirelessly with a software implemented signal generator in a microprocessor. (Author)

[en] A low jitter, low spur multiphase phase-locked loop (PLL) for an impulse radio ultra-wideband (IR-UWB) receiver is presented. The PLL is based on a ring oscillator in order to simultaneously meet the jitter requirement, low power consumption and multiphase clock output. In this design, a noise and matching improved voltage-controlled oscillator (VCO) is devised to enhance the timing accuracy and phase noise performance of multiphase clocks. By good matching achieved in the charge pump and careful choice of the loop filter bandwidth, the reference spur is suppressed. A phase noise of -118.42 dBc/Hz at a frequency offset of 1 MHz, RMS jitter of 1.53 ps and reference spur of -66.81 dBc are achieved at a carrier frequency of 264 MHz in measurement. The chip was manufactured in 0.13 μm CMOS technology and consumes 4.23 mW from a 1.2 V supply while occupying 0.14 mm² area. (semiconductor integrated circuits)

[en] To solve this situation it is necessary to organize manufacturing of marketable products at the enterprise but implementation of this goal requires investments allocations. In the frames of international cooperation we submit the following three projects: o modernization of construction and development of new modifications of electric stimulator of alimentary canal; o development and bringing into production of GSA-1 welding-gas generator installation; o development and bringing to a commercial level production of thermal elements for refrigerator devices, production of consumer's cooling devices; 1. Electric stimulator of alimentary canal (ESAC) is a medical a new level micro equipment, it was awarded diploma and medals of international exhibitions, including Medicine-92. ESAC is designed for electronic pulse stimulation of alimentary canal to restore its motor-evacuation activity. ESAC is the first among new devices which allows to make effective correction and activation of a number of degrading systems of human body without medicines, injures, a patient may stay at home and himself determine necessity of ESAC usage. 2. GSA-1 welding - gas generator installation uses ecologically safe power supply, that is hydrogen-oxygen produced by water electrolysing by caustic natrium or Potassium what excludes usage of calcium carbide and technical oxygen in gas-bags. The installation operates at 220 V voltage, frequency of 50 cycles/second, power supply 4 kw, its size is 865 sub x sub 728, weight - 75 kg. GSA-1 is designated for welding, cutting, soldering of steel and non-ferrous metals of the width to 4 mim. 3. Mastering of production of freon-free refrigerator installations based on thermoelectric transformers. The objective of the project is to master production and to manufacture consumers thermoelectric refrigerator-devices, conditioners, automobile bags-refrigerators. The main element vices, conditioners, automobile bags-refrigerators. The main element of all these cooling devices is thermo element consisting of two semiconductor branches with electron and hole conductivity connected in series. Phenomenon of thermoelectric cooling consists in heat releasing and absorbing on the boundary of two different conductors when current passes through them

[en] The goal of Experiment Cold was to test the limiting capabilities of the RATAN-600 radio telescope with the lowest noise possible at the present time in the telescope and radiometer system. The best radiometer (in terms of fluctuation sensitivity) is described based on a parametric amplifier with a closed-cycle helium cooling system, was used in the experiment; measures were taken to cool the radio telescope itself; and a method of controlling the numerous sources of interference was carefully thought out. All of these measures taken together allowed the authors to actually attain the fluctuation sensitivity of the radiometer on the sky and, after averaging the results over several months of observations, to reach a sensitivity close to the maximum possible for the RATAN-600 radio telescope. This limit turned out to be less than one millijansky in flux density and was set by faint background sources. Around 1980, when Experiment Cold was begun, the deepest surveys at centimeter wavelengths were being carried out at the Bonn 100-meter radio telescope with a limit of observation of roughly 14 millijanskys in flux density and a sensitivity of several millikelvins in brightness temperature (both limits determined by background sources)

[en] Considerable work has been done identifying and developing equipment and procedures that can be used to improve the survivability of a security communications network during a jamming assault. Insight is given into alternate communications methods that can be used to develop resistance to jamming by supplementing existing radio communications. The spatial properties of jamming are then discussed and examples of how these properties can be exploited are examined. Also discussed are spread-spectrum radios that are highly resistant to jamming and the importance of jamming exercises

[en] Our project, realised within the National Center for Nuclear Sciences and Technologies, is entitled the optimization and renewal of a radio-weather station. During this project we studied different sensors types and performances. Indeed, the work involved the development of these sensors and the communication with the data acquisition unit DAU16 to determine the data measured and collected by the unit. Theoretical studies helped us to conceive detectors types and their operation, and then it has been realized by the implementation of all sensors especially the Geiger-Muller detector called GP110i by Canberra. In order to improve the system and to avoid moving difficulty to have measurement data we have tested and studied two possibilities to use network instead of using cable connection: the PLC PK2100 and the system applied to Oued Medjerda.

[en] After a short description of the mine producing 1 000 t/year of uranium metal, the solution of numerous problems can be effected by a convenient and quick means of communication from person to person. A 450MHz UHF radio signal is propagated directly from a conductor and from an antenna

[en] A wideband digital low-frequency radio receiver for scientific applications is described. The portable battery-powered instrument has the capability to record electric field strengths in the frequency range from ∼4 Hz to ∼400 kHz with a sampling frequency of 1 MHz, an amplitude resolution of ∼35 µV and a timing accuracy of ∼12 ns whilst performing continuous digital waveform recordings for several days. The instrument strictly follows a modular design such that it can be extended to higher frequencies and timing accuracy when the corresponding digital technology becomes available. The low-cost radio receiver can be developed into an interferometric network by synchronizing individual radio receivers to map the low-frequency radio sky. The first measurements of atmospheric electric fields are carried out at Exmoor National Park in Southwest England to illustrate the capabilities of the novel instrument

[en] A high performance 10-bit 100-MS/s two-channel time-interleaved pipelined ADC is designed for intermediate frequency 3G receivers, and OTA is shared among the channels for low power dissipation. Offset mismatch, gain mismatch and time skew mismatch are overcome by OTA sharing, increasing the accuracy of each channel and global passive sampling respectively. The linearity deterioration caused by the charge injection of the output switch and the crosstalk of the off-switch capacitor is removed by modifying the clock signal arrangement. The total power consumption of the presented ADC is 70 mW from a 3.3-V power supply. Fabricated in a 180-nm CMOS process, the core of the prototype occupies an area of 2.5 x 1.5 mm², achieving more than 70-dB spurious-free dynamic range and over 56-dB signal-to-noise distortion ratio over the Nyquist input band at 100-MHz sampling frequency. (semiconductor integrated circuits)