The paper is focused on the forthcoming IEEE 802.11ax standard and its influence on Wi-Fi networks performance. The most important features dedicated to improve transmission effectiveness are presented. Furthermore, the simulation results of a new transmission modes are described. The comparison with the legacy IEEE 802.11n/ac standards shows that even partial implementation of a new standard should bring significant throughput improvements.

The Corded Ware culture societies inhabiting the Carpathian zone used various outcrops of flints to processing axes: Volhynian, Turonian (the Świeciechów and the Gościeradów types), Jurassic A and G-type, cretaceous K-type as well as siliceous marl and radiolarite. From the analysed area 81 axes associated with the Corded Ware culture are known. Most of them come from funeral sites — from grave pits or burial mounds. The predominance of the Volhynian flint is observable in the whole area to the east of Wisłok River, basins of the San River, and in the upper basins of the Tisza and Dniester Rivers. Axes from niche graves on the Rzeszów Foothills, where the Świeciechów flint prevails, are specific in this scope or raw materials distribution. Dispersion of flints can be used indirectly as basis for reconstructing movements of human groups using these raw materials, as well as determining directions of their interactions. It can be noticed that communities of the Corded Ware culture from the Dniester Basin resembled in this respect their counterparts from the Roztocze and the Sokal Ridge, while those from the Rzeszów Foothills shows connections both with the“Volhynian zone” and the Lesser Polish Małopolska Upland.

On the Transylvanian territory 19 axes have been recorded that date to different times during the 7th and 8th c. AD, and which create a chronological sequence that will be shown in the text below. These 19 artefacts were retrieved from: 6 cemeteries — 10 finds; 1 military guard post / observation post for the surveillance of the area — 1 find; a settlement / house — 1 find; and discovered as stray finds: at 3 specified sites — 4 finds, within the territory of the county — 3 finds. The shape of the artefacts is the main criterion used to develop the typological groups of axes found in the Transylvanian plateau. Accordingly, five main types have been defined: 1st type — Axe with a poll, hammer type; 2nd type — Axe with a long poll in the shape of a rectangular bar; 3rd type — Axe with a fan-shaped blade and a long poll in the shape of a rectangular bar; 4th type — Axe with a round poll; 5th type — pole-axe. Taking into consideration the contexts of the discoveries and known analogies, these axes can be dated to different points in time creating a chronological sequence spanning over the 7th and 8th centuries. Most of the axes dated from the 7th and 8th centuries in Transylvania were found in warrior graves or funerary contexts, or together with other weapons, thus providing grounds for their inclusion within the category of weapons. This fact, combined with the series of typological features, allows to include these artifacts in the category of battle axes.

The paper focuses on the optimization of IEEE 802.11ax dense networks. The results were obtained with the use of the NS-3 simulator. Various network topologies were analyzed and compared. The advantage of using MSDU and MPDU aggregations in a dense network environment was shown. The process of improving the network performance for changes in the transmitter power value, CCA Threshold, and antenna gain was presented. The positive influence of BSS coloring mechanism on overal network efficiency was revealed. The influence of receiver sensitivity on network performance was determined.

The paper presents an analysis of BSS coloring scheme defined in IEEE 802.11ax standard. The efficiency of dense networks for different scenarios was analyzed and compared. This analysis covers various topologies and work configurations through the use of multiple parameters of the PHY and MAC layers. A positive impact of the coloring mechanism on the QoS was observed. The study also analyzed the impact of the RTS/CTS mechanism on the obtained network performance and adequate prioritization of various traffic classes. It was shown that the proper selection of the coloring mechanism parameters in the IEEE 802.11ax standard has a strong impact on QoS and the performance of dense networks.