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Satellite services in the High North are utilized extensively for both communication purposes and for earth and climate observations. This paper presents results of two year measurements at 20 GHz and co-sited meteorological data. The results suggest that with 7–8 dB margin, services can be provided with 99 % availability for systems with elevation angles as low as 3.2° and 3 dB for elevation angles...
A channel sounder operating in the 60 GHz band is described. It is designed using off-the-shelf components and programmed using model based design. Results from indoor measurements are provided and discussed in the context of published channel models for similar environments. The results include LOS measurements from a narrow office corridor and mixed LOS and NLOS measurements from an open-space canteen.
Data from a weather radar located above the polar circle in the North Sea are used to estimate the rain attenuation for a satellite link towards a geostationary satellite operating at Ka-band. Radar reflectivity data are obtained along the slant path from a beacon receiver located close to the radar towards the satellite, and the results of the estimator are compared with measurements of a beacon...
• A short overview of ANTARES is given • Interference in the forward link may increase the noise level significantly • How much will vary from beam to beam • In the return link, the interference put constrains on the interference cancelling algorithm that must reduce the MAI below the required level.
ANTARES is a study within the Iris Programme of the European Space Agency, to design a satellite communication system that will provide ATM services over Europe and the surrounding oceanic areas beyond 2020–2025. As part of the development phase, the interference level that can be expected to be experienced in the mobile link is estimated. The interference level is simulated using flight traces and...
In order to meet the demand for increased capacity in wireless networks, incorporating femtocells within the coverage of macrocells constitutes one of the strategies that currently receives most attention from both industry and academia. Femtocells may either be part of a HetNet as standardised within 3GPP, or constitute the secondary system in cognitive networks. Power control is a useful mechanism...
We study the use of reinforcement learning to model Dynamic Spectrum Access in a realistic multi-channel environment. Three different approaches from the literature on the multi-armed bandit problem are compared on a set of realistic channel access models — two are based on stochastic models of the channel occupancy, while a third assumes an adversarial model.
AeroMACS is a system currently under development for airport surface communications. It is based on the IEEE802.16-2009 standard, and is developed in cooperation with the WiMAX forum. The frequency band allocated to AeroMACS is 5091–5150 MHz. When specifying the AeroMACS system, knowledge of typical propagation conditions at airports is of importance. Typically, path loss models are used to estimate...
AeroMACS is a system currently under development to be used for airport surface communications. It is based on the IEEE802.16–2009 standard, and is developed in cooperation with the WiMAX forum. The frequency band allocated to AeroMACS is 5091–5150 MHz. When specifying the AeroMACS system, knowledge of typical propagation conditions at airports is of importance. Typical path loss models are necessary...
This paper contains results from compatibility studies between AeroMACS and other systems operating in the same or adjacent frequency bands. These systems are RLAN, AMT, MLS and FSS feeder links. For compatibility with the terrestrial systems, the minimum distance to interferer is calculated, i.e. the minimum distance an interfering transmitter can be from a victim receiver without degrading the system...
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