Thomas Nicolay

Obtaining true-random binary numbers from a weak radioactive source

In this paper, we present a physical random number generator (RNG) for cryptographic applications. The generator is based on alpha decay of Americium 241 that is often found in common household smoke detectors. A simple and low-cost implementation is shown to detect the decay events of a radioactive source. Furthermore, a speed-optimized random bit extraction method was chosen to gain a reasonable high data rate from a moderate radiation source (0.1 μCi). A first evaluation by applying common suits for analysis of statistical properties indicates a high quality of the data delivered by the device.

Baseband signal processing of digital video broadcasting direct-conversion zero-IF tuners

Based on a direct conversion zero-IF concept for a single-chip tuner IC for the digital video broadcasting handheld (DVB-H) reception, the required analogue signal processing in the tuner IC and the digital signal processing in the subsequent digital baseband processor is described. Measurement results for the IQ-error correction are presented, demonstrating the received performance. The shown deliverables facilitate the choice of the required parameters in order to achieve the best dynamic behaviour and noise performance.

ZipMode: Implementation of a Receiver Localization System using ASTRA Satellites

*† ‡ § The authors present the implementation of a new localization system for satellite receivers. The system uses two geostationary collocated satellites to measure the range difference to a stationary DVB-S receiver. Algorithms and hardware implementation of a prototype system are introduced. Measurements and field tests are performed to prove the feasibility of the system.

Hybrid two antenna microwave sensor for nondestructive material characterisation

With increasing production and process requirements, the need for cost efficient, simple and reproducible measurement and test methods, which are not only nondestructive but also contactless, steadily rises. We are developing a system whose core part is an LTCC (low temperature cofired ceramic) hybrid, which provides whole RF functionality and delivers baseband signals for further processing. The operating frequencies of the system are the ISM bands at 2.45 GHz and 5.8 GHz. In order to obtain specifications necessary for the final LTCC design, we have developed a reference prototype. We present the measurement principle and first results for the prototypes.

Telemetric chain link force measurement in coal mining armored face conveyors

The newly developed and patent pending telemetric measurement system monitors traction forces in the chain links of an underground coal mine armored face conveyor. The sensor system mainly consists of the sensor unit itself and the signal processing and transmitter unit. All units, including the antenna, are integrated in a specially developed catch of the armored face conveyor. The receiver station contains the receiver module, a visualization tool and the conveyor belt control unit. The system works under ISM conditions at frequencies of 433 MHz.

RF identification in the use of belt rip detection [mining product belt haulage]

Radio frequency identification (RFID) is frequently discussed as a means to identify different products by reading the product codes in its respective transponders. The main topics are its use in logistics such as the administration of streams of goods in storage areas and in dealing with consumer goods. In this paper, we discuss the transfer of this technology to the sector of belt haulage of mining products. The belt rip detection system for conveyor systems, realized in this work, provides a high degree of belt protection for high risk areas because of its combination of rip recognition mechanism, robust design and sophisticated control software.