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In recent years Mobile Network Operators (MNOs) worldwide are extensively deploying LTE networks in different spectrum bands and utilising different bandwidth configurations. Initially, the deployment is coverage oriented with macro cells using the lower LTE spectrum bands. As the offered traffic (i.e. the requested traffic from the users) increases the LTE deployment evolves with macro cells expanded with additional capacity boosting LTE carriers in higher frequency bands complemented with micro or small cells in traffic hotspot areas. For MNOs it is crucial to use the LTE spectrum assets, as well as the installed network infrastructure, in the most cost efficient way. The dynamic spectrum allocation (DSA) aims at (de)activating the available LTE frequency carriers according to the temporal and spatial traffic variations in order to increase the overall LTE system performance in terms of total network capacity by reducing the interference. This paper evaluates the DSA potential of achieving the envisaged performance improvement and identifying in which system and traffic conditions the DSA should be deployed. A self-optimised network (SON) DSA algorithm is also proposed and evaluated. The evaluations have been carried out in a hexagonal and a realistic sitespecific urban macro layout assuming a central traffic hotspot area surrounded with an area of lower traffic with a total size of approximately 8×8 km². The results show that up to 47% and up to 40% possible DSA gains are achievable with regards to the carried system load (i.e. used resources) for homogenous traffic distribution with hexagonal layout and for realistic site-specific urban macro layout, respectively. The SON DSA algorithm evaluation in a realistic site-specific urban macro cell deployment scenario including realistic nonuniform spatial traffic distribution shows insignificant cell throughput (i.e. served traffic) performance gains. Nevertheless, in the SON DSA investigations, a gain of up to 25% has been observed when analysing the resource utilisation in the non-hotspot cells. [ABSTRACT FROM AUTHOR]

Positioning in wireless networks is mainly used for safety, gaming, and commercial services. It is expected to increase in popularity when emergency call services become mandatory as well as with the advent of more advanced location-based services and mobile gaming. In this article, we discuss and illustrate the possibilities and fundamental limitations associated with mobile positioning based on available wireless network measurements. The possibilities include a sensor fusion approach and model-based filtering, while the fundamental limitations provide hard bounds on the accuracy of position estimates, given the information in the measurements in the most favorable situation. The focus of this article is to illustrate the relation between performance requirements, such as those stated by the Federal Communications Commission (FCC), and the available measurements. Specific issues on accuracy limitation in each measurement, such as synchronization and multipath problems, are briefly commented upon. A geometrical example, as well as a realistic example adopted from a cell planning tool, are used for illustration. [ABSTRACT FROM PUBLISHER]

Transmission power control is an important means to manage the radio resources in wireless communications. The performance, however may be reduced due to time delays as in any controlled system. Most controllers to date are designed without considering time delays, which may result in oscillatory or unstable systems. To overcome these problems, time delay compensation (TDC) is introduced. The main idea is to adjust the measurements [e.g., signal-to-interference ratio (SIR)] to include the effects of issued but not yet applied power control commands. TDC thereby improves the stability and performance of an arbitrary power control algorithm. The benefits are illustrated by simulations using some popular power control algorithms [ABSTRACT FROM PUBLISHER]

Forest management planning aims at fulfilling the goals of the forest owner. Scheduling treatments of forest stands, both in time and space, have been well investigated previously. Usually, however, these studies have assumed spatially discrete stands, representing imagined treatment units. Furthermore, the stands have been inventoried using ocular methods with varying and unknown precision. As an alternative to this conventional way of describing the forest, an objective circular plot inventory method was used, in the present investigation, to represent the forest on a 400 ha estate. Kriging was used to estimatespatially continuous forest characteristics from the georeferenced inventory plots. Spatial discontinuity, for example, between young andold forests, was handled by making an initial stratification of the forest into age-classes. This approach enabled several spatially continuous variables, of interest to forest management planning, to be estimated at all locations. The stratification made it possible to preserve the real-world mosaic of stands resulting from intensive management as, e.g., clear-cutting boundaries. [ABSTRACT FROM AUTHOR]

We investigate a 2,000-year genetic transect through Scandinavia spanning the Iron Age to the present, based on 48 new and 249 published ancient genomes and genotypes from 16,638 modern individuals. We find regional variation in the timing and magnitude of gene flow from three sources: the eastern Baltic, the British-Irish Isles, and southern Europe. British-Irish ancestry was widespread in Scandinavia from the Viking period, whereas eastern Baltic ancestry is more localized to Gotland and central Sweden. In some regions, a drop in current levels of external ancestry suggests that ancient immigrants contributed proportionately less to the modern Scandinavian gene pool than indicated by the ancestry of genomes from the Viking and Medieval periods. Finally, we show that a north-south genetic cline that characterizes modern Scandinavians is mainly due to the differential levels of Uralic ancestry and that this cline existed in the Viking Age and possibly earlier., Competing Interests: Declaration of interests A.H., K.H.S.M., K.S., and S.S.E. are employees of deCODE genetics., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)