A mobile users’ network with power control on traffic channels, as it is GSM, is considered in this paper. It is analyzed the influence of busy channels reallocation on the necessary emission power. The main principle in reallocation is that users who need greatest power for their connections take traffic channels of the first carrier where power is always maximum. It is assessed that reallocation process is not more complicate than the simplest handover processes. It is proved that this method may be used to decrease emission power of carriers after the second one. Power saving depends on number of carriers, environmental propagation coefficient and users’ density distribution in the cell. The results are verified by originally developed simulation program.

This paper presents a two-dimensional Markov traffic model of the mobile users' network where there exist handover calls from the surrounding cells to the considered cell and where, also, primary calls are generated. The two emphasized types of calls form together mixed traffic. The new, two-dimensional model allows us to calculate some characteristic variables for the systems, which may not be determined based on the analysis of one-dimensional model. The developed simulation program is verified comparing the obtained system state probabilities as also primary and handover calls loss rate to the corresponding values from the calculation process. We analyzed cells with a number of channels reserved only for handover calls. This system performances are compared to the performances of some other systems from literature and it is proved that their characteristics are comparable whereby our system improves handover calls dropping rate. It is also proved that users' speed increase and cell radius decrease cause both primary and, especially, handover calls loss rate increase. The results of calculation and simulation are obtained after a number of iterations (calculation or simulation cycles), where the new loss probability values from one iteration become the input values for the next iteration. In the case that call loss values do not converge during simulation, we implemented the original algorithm for input call loss probability estimation for the next iteration.

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In this paper we compared the time required for the successful jamming of remote controlled improvised explosive devices activation using active and responsive jamming methods. As a representative of active jamming method we analyzed jamming signal generation using frequency sweep. For the analysis of the possible activating signal presence based on responsive jamming procedures we first supposed Fast Fourier Transform (FFT) implementation and compared its analysis rate to the rate of sweep jamming. Taking into account the current technology state, it is proved that the time required to achieve the successful jamming relied on FFT analysis may be less than in the case of active sweep jamming. After that we considered pros and cons for energy detector and matched filter detector implementation in responsive jamming. For these two detector types it is shown how to determine the number of analysis blocks to achieve approximately the same number of collected samples as in the case of FFT implementation, starting from the probabilities of false detection and miss of detection.