There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

It is shown that, particularly for terrestrial cellular telephony, the interference-suppression feature of CDMA (code division multiple access) can result in a many-fold increase in capacity over analog and even over competing digital techniques. A single-cell system, such as a hubbed satellite network, is addressed, and the basic expression for capacity is developed. The corresponding expressions for a multiple-cell system are derived. and the distribution on the number of users supportable per cell is determined. It is concluded that properly augmented and power-controlled multiple-cell CDMA promises a quantum increase in current cellular capacity. >

On the capacity of a cellular CDMA system

Information Theory and Reliable Communication

: This thesis applies neural network feature selection techniques to multivariate time series data to improve prediction of a target time series. Two approaches to feature selection are used. First, a subset enumeration method is used to determine which financial indicators are most useful for aiding in prediction of the S&P 500 futures daily price. The candidate indicators evaluated include RSI, Stochastics and several moving averages. Results indicate that the Stochastics and RSI indicators result in better prediction results than the moving averages. The second approach to feature selection is calculation of individual saliency metrics. A new decision boundary-based individual saliency metric, and a classifier independent saliency metric are developed and tested. Ruck's saliency metric, the decision boundary based saliency metric, and the classifier independent saliency metric are compared for a data set consisting of the RSI and Stochastics indicators as well as delayed closing price values. The decision based metric and the Ruck metric results are similar, but the classifier independent metric agrees with neither of the other metrics. The nine most salient features, determined by the decision boundary based metric, are used to train a neural network and the results are presented and compared to other published results. (AN)

/pdf/nonlinear-time-series-analysis-1j3a35n4y3.pdf

Nonlinear Time Series Analysis.

This document provides updates to IEEE Std 802.16's MIB for the MAC, PHY and asso- ciated management procedures in order to accommodate recent extensions to the standard.

IEEE Standard for Local and Metropolitan Area Networks Part 16: Air Interface for Fixed Broadband Wireless Access Systems Draft Amendment: Management Information Base Extensions

One of the main revolutionary features of 5G networks is the ultra-low latency that will enable new services such as those for the future smart vehicles The 5G technology will be able to support extreme-low latency Thanks to new technologies and the wide flexible architecture that integrates new spectra and access technologies In particular, Visible Light Communication (VLC) is envisaged as a very promising technology for vehicular communications, since the information can flow by using the lights (as traffic-lights and car lights) This paper describes one of the first experiments on the joint use of 5G and VLC networks to provide real-time information to cars The applications span from road safety to emergency alarm

Experimental measurements of a joint 5G-VLC communication for future vehicular networks.

This paper deals with the performance evaluation of an efficient medium access control (MAC) technique based on the use of an adaptive modulation and coding (AMC) scheme that significantly improves the downstream data rate and guarantees specific quality of service (QoS) requirements in wireless communication systems. Basically, the access scheme considered in this paper relies on physical channel monitoring and state mapping into a variable rate packet format. In particular, a suitable analytical model is proposed herein in order to predict the system performance, i.e., the average packet queuing delay in the case of a non-stationary transmission channel. Comparisons between analytical predictions and simulation results are provided to validate our model and highlight the improvement of the AMC technique with respect to a static rate allocation scheme, especially in the case of heavy tailed traffic conditions.

Performance Evaluation of a Link Adaptation Technique for High Speed Wireless Communication Systems

This paper deals with a random reservation TDMA protocol able to support constant bit-rate services as well as variable bit-rate services. In particular, we consider here the case of voice communications and data transmissions in a fading channel environment with nonindependent errors. Voice terminals are assumed to have higher priority than data terminals, in accessing the shared channel. A suitable analytical approach is proposed in order to evaluate the data and voice subsystem performance. Computer simulations are also shown in order to validate the obtained analytical predictions. The results shown here highlight that the proposed protocol permits an efficient integration of voice and data transmissions in the same wireless network even in the presence of a nonideal transmission channel.

Performance evaluation of a reservation TDMA protocol for voice/data transmission in personal communication networks with nonindependent channel errors

Wireless ad hoc networks are an emerging technology. These networks are composed of mobile nodes and may adopt different topologies depending on the nature of the environment. Nevertheless, they are vulnerable to network layer attacks that cannot be neutralized easily. In wired networks, firewalls improve the level of security by means of packet filtering techniques that determine what traffic is allowed, thereby reducing the impact of such attacks. In this work, we overview the requirements to adapt firewalls to wireless ad hoc networks and highlight the advantages of the use of filtering techniques based on Bloom filters.

Romano Fantacci

Papers

Experimental measurements of a joint 5G-VLC communication for future vehicular networks.

Performance Evaluation of a Link Adaptation Technique for High Speed Wireless Communication Systems

Performance evaluation of a reservation TDMA protocol for voice/data transmission in personal communication networks with nonindependent channel errors

Efficient packet filtering in wireless ad hoc networks

A matching game for tasks offloading in integrated edge‐fog computing systems