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To obtain the attenuation level in links at frequencies higher than 10 Ghz, rain is the most important factor to consider. In spite of the existence of statistical models to calculate the rain attenuation –such as ITU-R standards- sometimes it is necessary to have an approximation to real-time rain-attenuation in the link. In this paper a sensor network that monitors the rain rate of different regions...
Time series are a set of a variable values sampled in equally time periods. They can be obtained through the measurement of some phenomenon in order to be analyzed and characterized. In this document, a model that characterizes a Ka-band signal attenuation and its validation is proposed. This characterization is based on the signal monotony and conditional probability which are validated through a...
Along with the recent developments around wireless optical systems, as an alternative to solve the bottlenecks at the last mile, it has emerged the need of having a proper understanding of the propagation of a beam of light at different atmospheric conditions that appear at the channel. The implementation of a graphic interface in MatLab that simulates the models that characterize the losses in an...
In this paper, the effects of co-channel interference in a HAPS-based cellular system are analysed, comparing such effects in two frequency reuse scenarios with terrestrial systems. The CIR is evaluated for both schemes, and the HAPS-based cellular system shows significant improvements in the reduction of co-channel interference over terrestrial systems, even when compared to sectorised configurations.
A geometric model that describes a multipath propagation for a fixed wireless communication system between a high altitude platform and a fixed terrestrial user is presented. The model describes the propagation of the reflected signals that are able to reach the receiver as a consequence of all the scatterers located inside the system coverage area. The establishment of a particular geometry characterizing...
The performance of HAPS systems using a multiple-input multiple-output (MIMO) wireless link is analysed in this paper. The characteristics and key features of MIMO systems are discussed, especially when used for HAPS applications. The capacity improvement is examined, as the number of transmit and receive antennas is increased, while the BER of the system is reduced, since the total received power...
A method to estimate and accurately distribute the building population and cellular traffic is presented and explained in this paper. This technique makes use of cellular traffic measurements to determine actual traffic on a per-existing-cell basis; these measurements are then used with characteristic mobility models of the population of the building in consideration, to produce traffic maps, which...
In frequencies over 10 GHz the rain is the most important factor to take in count to evaluate the attenuation level. For several kinds of applications is very useful to known this attenuation in the link every moment while the link is in operation to implement some strategy to mitigate it. According to the ITU-R, there is a procedure to calculate the rain attenuation, however this methodology gives...
This paper shows the procedure to gather propagation measurements to characterize the path loss of cantera stone for the penetration of RF signals at UHF frequencies in various Mexican historic buildings. It is the first time that such material is tested for RF propagation and since there are many buildings made of this material in many cities in Mexico the results obtained are the base for future...
The demand of the telecommunication services has been growing these last years. The analysis of the transmission of a RF signal through a wireless channel is a key point in the overall performance. Several kinds of channels models have been studied, like Gaussian, Ricean and Rayleigh, but using only one of them to evaluate the communication system is not enough; a real channel doesn't have the same...
A detailed cellular existing coverage analysis was performed for the Informatics and Electronics Centre Building (CIE) at ITESM Campus Queretaro, using novel propagation modelling tools such as Measurement-based prediction (MbP) to predict signal strength levels across the five-storey building. An extensive set of radio measurements was performed in the 1900 MHz band to construct received signal strength...
A common practice to avoid the attenuation presented in a wireless communication system is using fading mitigation techniques. Examples of those techniques are the adaptive systems. The proposal of this article is about a system that can switch its transmission and reception characteristics according the bit error rate (BER) between the sent and received data. The system (simulated in Matlab) will...
The high altitude platforms stations (HAPS) represent one attractive option today for telecommunications applications. In the evaluation of these systems are necessary channel models to obtain the performance of them. In this paper, a statistical switched broadband channel model and a channel model based on time series generator are postulated and analyzed by simulation, representing several conditions...
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