Channelization is the task of channel selection in a communications receiver. Usually it comprises down-conversion of the signal to base-band and channel filtering. To be able to influence the characteristics of channelization by means of software it is advantageous to realize as much as possible of the channelization functionality with digital signal processing. In base-stations several channe...

For an ad hoc IEEE 802.11 WLAN we investigate how the stations' incentives to launch a backoff attack i.e., to configure small minimum and maximum CSMA/CA contention windows in pursuit of a larger-than-fair bandwidth share, affect a proposed capacity-fairness index (CFI). We link CFI to the network size, "power awareness," a station's perception of the other stations' susceptibility to incentiv...

Maps of pollutants concentration are usually generated by means of interpolation and extrapolation methods. The quality of the results depends mainly of the number of permanent or temporary measuring stations. This paper deals with a method for the virtual densification of the network of stations. The method creates "virtual measuring stations". It aims at improving the quality of interpolation...

We study a facility location problem motivated by requirements pertaining to the distribution of charging stations for electric vehicles: Place a minimum number of battery charging stations at a subset of nodes of a network, so that battery-powered electric vehicles will be able to move between destinations using “t-spanning” routes, of lengths within a factor t > 1 of the length of a shortest ...

This paper identifies factors that encourage or reduce pick-pocketing at underground rail stations through a case study analysis of the London Underground. Negative binomial Poisson regression models found possible predictor variables of pick-pocketing selected from the internal characteristics of stations, and features of their nearby surroundings. Factors that increased risk were those associ...

Original scientific paper Air quality monitoring stations are used for quick and reliable assessment of air quality. Although the stations are expensive, very often their number on certain territory exceeds optimal number of stations leading to their redundancy, increased costs, overlapping of data etc. To enable analysis of quantitative and qualitative criteria, authors propose an approach bas...

Pico base stations are an important instrument to increase the capacity of mobile radio networks. Due to the limited spectrum availability it will be necessary to operate macro and pico base stations on the same frequency bands. In this case the transmit power imbalance between different base station types creates new interference situations. Coordinated beamforming is one method of base statio...

Customers move through a series of M service stations. Each customer, independent of all others, requires service from only one of the stations, for a duration of 1 time unit, this being station i with probabilityp1. The customer has zero service at all the other stations, but there is no overtaking between the customers, and so queueing occurs. In the case where there is unlimited waiting room...

This work provides an up to date measurement-driven examination of the spatial characteristics of network resource usage. The data set used is from a large nationwide 3G cellular network comprised of several thousand base stations. Firstly, we discuss our data set and its potential application. Next, we examine the spatial correlation between base stations in terms of radio resource usage. We f...

This paper revievTS a number of queueing models which deal with situations where a single service station has to concern itself with a number of missions and at any given time one of them only can be performed.