This paper analyzes the reliability and throughput of the telegram-splitting concept in the presence of inter-system and intra-system interference. Using telegram splitting, the data of one telegram is split into multiple sub-packets, which are then transmitted with temporal spacing. As a result, collisions with other telegrams destroy only some sub-packets that can be recovered using forward error correction. Consequently, the reliability of the data transmission in case of inter-and intra-system interference-a significant problem in license-exempt bands-is highly improved. In this paper, probabilities for the resulting telegram error rate of random media access systems using telegram splitting are derived. Furthermore, the achievable throughput is analyzed. The theoretical considerations in addition to simulation results prove the significant gain of the telegram-splitting concept for telemetry systems.

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Supplementary information for global navigation satellite systems help to improve accuracy, may accelerate a first fix, and could enable localization even in difficult reception scenarios. Contemporary broadcast systems based on datacasting ease implementation of add-on services besides the actual video and audio services. This paper details on the aspects of such services designed for digital video broadcasting for handhelds (DVB-H) in a single frequency network to supplement a global positioning system receiver (GPS). Multiple approaches involving differential and assisted GPS as well as high and low level signalization in DVB-H are analyzed in this paper. From the corresponding results recommendations concerning the implementation of such services are derived

Three-phase AC-AC series-resonant converters using pulse modulation with internal frequencies of 10 kHz, and suitable for multi-kilowatt power levels, have the excellent characteristics of generating multi-phase bipolar waveforms with reversible power flow, low distortion and fast system response.This proposal presents a novel converter topology with only six switches. The switch current is a half period of the sine wave as generated by the resonant network. The ai/at is limited during the switching interval. The switching loss equals the produkt of switch voltage and switch current is consequently low. The principle of soft-switching can reduce the total power losses by one third to one half compared to the previous series-resonant converter without soft-switching (2).The converter controls the output voltages as well as the input current. The harmonic distortion of both waveforms is low. The power factor of the input currents is controlled.

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