Gino Luca Masini

The effect of precipitation on microwave LMDS networks-performance analysis using a physical raincell model

This article proposes an application of the EXCELL model to microwave local multipoint distribution systems. With EXCELL, validated in many years of observations with a meteorological radar, rain is modeled by a population of exponentially-profiled raincells. Their statistics can be made to honor any given rainfall cumulative distribution function. It is, thus, possible to simulate synthetic precipitation events so that rain effects on various radio link topologies (point-to-point or multipoint) can be evaluated on each event. Both copolar and crosspolar effects were modeled, and the C/I and C/N statistics were evaluated for a large number of events.

Dynamic fade restoration in Ka‐band satellite systems

Atmospheric precipitation can seriously affect the propagation of centimeter and millimeter electromagnetic waves. As a consequence, in some applications, it is necessary to make use of a fade countermeasure technique in order to satisfy the system availability and quality requirements. This study analyses the performance of a satellite-based system in geo-stationary orbit operating at 20 GHz, dynamically assigning the antenna directivity pattern to counteract tropospheric attenuation. The on-board power is spatially distributed over the covered region to minimize, at any time, the number of users undergoing outage because of the tropospheric attenuation. Both the aspects of broadcasting and telecommunication services are addressed. The reflector antenna of the system is supposed to be illuminated by a cluster of feeds driven by a set of excitation coefficients, continuously modified and optimized according to the meteorological information derived by processing METEOSAT satellite data and ECMWF (European Centre for Medium-Range Weather Forecasts) data. Copyright

LTE-WLAN aggregation (LWA) in 3GPP Release 13 & Release 14

Integrating different radio access technologies (RATs) is one effective method to meet the demand to provide ever increasing data rates to the users. For integrating LTE and WLAN in particular, the purpose is to enhance the operators control of when the UE uses WLAN. Another aim, in addition to better network control on which RAT is used, is the possible data aggregation which enables simultaneous utilization of both resources. In this paper, we present LTE-WLAN Aggregation (LWA) as specified in 3GPP and compare it to the LTE-WLAN Radio Level Integration with IPsec tunnel (LWIP), also specified in 3GPP. In addition, we provide simulation results comparing the schemes in an example scenario.