Petrica Ciotirnae

Extended Partially Overlapped Channel Interference Model and Study for 802.11 Wi-Fi Communications

In this paper the authors extend the tests and model verification related to the partially overlapped channel interference in Wi-Fi communications. Recently more and more papers have investigated the side effects of the channel interference on the throughput parameter. The paper proposes a theoretical model and an experimental approach to obtain useful information regarding channel allocation and spatial reuse in conditions of the intense traffic, by exploiting the data related to the site interference. The paper results determined how smart planning of the operating channel versus the observed interference spectrum configuration can reduce the amount of interference impact and eventually improve Wi-Fi network performance and it also confirmed an alternative way to avoid interferences, without changing the channels configuration (desired or jamming), which consists on getting out of the jamming signals interference range, after estimating this range.

High-performance pattern recognition system using an improved neural classification chain and decision fusion on multispectral information

The performance level of pattern recognition (PR) systems can be improved using in a proper way new powerful artificial neural networks inside of its classification chains and respectively, decision fusion techniques on available multispectral information. Consequently, to increase the pattern recognition performances, an improved neural classification chain and respectively, an evolutive version of Sugenos fuzzy integral based on high-resolution radar (HRR), video and thermal imagery use are described. To confirm the broached theoretical aspects, a real image database was used.

Some considerations about third-order statistics for different types of radar signals

The signal processing techniques based on higher-order statistics are used in many applications due to their interesting properties. These techniques are very useful when the signals are affected by the gaussian noises. In this paper the higher-order moments and the moment spectra for deterministic signals are theoretically described. An analysis of the third-order statistics for some particularly signals used in radar domain is presented.

Characteristics of crowdsourcing for outdoor radio fingerprinting positioning

Positioning systems based on location fingerprinting have become an area of intense research, mainly with the aim of providing indoor localization. Many challenges arise when trying to deploy location fingerprinting to an outdoor environment. The main problem is achieving coverage of large outdoor spaces, which costs time and needs an intensive data gathering effort. This paper proposes the use of mobile crowdsourcing in order to build a fingerprint database consisting of Wi-Fi networks received signal strength. The primary objective of this paper is to prove the feasibility of outdoor positioning using Wi-Fi crowdsourced data by showing that Wi-Fi networks are ubiquitous in urban areas. We then examine the gathered data and report our findings on challenges in building and maintaining a large-scale crowdsourced fingerprint database, the influence of fading on crowdsourced measurements. As Wi-Fi access-points are shown to exhibit mobility, we also propose and analyze methods for detecting and classification of mobile and static access-points.

5G propagation: Current solutions and future proposals

Technology has reached the point when it is required to design a new network, 5G, that can offer efficiency, higher speeds and a converged fiber-wireless topology. It is supposed to offer high speed wireless access to the Internet by using very-wide-bandwidth radio channels for data access speeds up to 10Gb/s. Furthermore, other parameters that customers seem to need as quickly and as much are: high mobility, ubiquitous coverage, low latency, massive number of devices and low cost/energy consumption as it was discussed in other papers written on the same subject [1]-[5]. This paper intends to offer a solution to achieve coverage, speeds and low latency for massive access in an urban area. Few technical parameters will be simulated in ATDI ICS Telecom 12.3.1 software.