Development and implementation of an adaptive digital beamforming network for satellite communication systems

The use of adaptive digital beamforming techniques has, until recently, been largely restricted to high performance military radar systems. Recent advances in digital technology, however, have enabled the design of single chip digital beamforming networks. This, coupled with advances in digital signal processor technology, enables complete beamforming systems to be constructed at a lower cost, thus making the application of these techniques to commercial communications systems attractive. The design and development of such an adaptative digital beamforming network are described. The system is being developed as a proof of concept laboratory based demonstrator to enable the feasibility of adaptive digital beamforming techniques for communication systems to be determined. Ultimately, digital beamforming could be used in conjunction with large array antennas for communication satellite systems. This will enable the simultaneous steering of high gain antenna beams in the direction of gr...Peer ReviewedPostprint (published version

Optimising Humanness: Designing the best human-like Bot for Unreal Tournament 2004

This paper presents multiple hybridizations of the two best bots on the BotPrize 2014 competition, which sought for the best humanlike bot playing the First Person Shooter game Unreal Tournament 2004. To this aim the participants were evaluated using a Turing test in the game. The work considers MirrorBot (the winner) and NizorBot (the second) codes and combines them in two different approaches, aiming to obtain a bot able to show the best behaviour overall. There is also an evolutionary version on MirrorBot, which has been optimized by means of a Genetic Algorithm. The new and the original bots have been tested in a new, open, and public Turing test whose results show that the evolutionary version of MirrorBot apparently improves the original bot, and also that one of the novel approaches gets a good humanness level.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Resource location based on precomputed partial random walks in dynamic networks

The problem of finding a resource residing in a network node (the \emph{resource location problem}) is a challenge in complex networks due to aspects as network size, unknown network topology, and network dynamics. The problem is especially difficult if no requirements on the resource placement strategy or the network structure are to be imposed, assuming of course that keeping centralized resource information is not feasible or appropriate. Under these conditions, random algorithms are useful to search the network. A possible strategy for static networks, proposed in previous work, uses short random walks precomputed at each network node as partial walks to construct longer random walks with associated resource information. In this work, we adapt the previous mechanisms to dynamic networks, where resource instances may appear in, and disappear from, network nodes, and the nodes themselves may leave and join the network, resembling realistic scenarios. We analyze the resulting resource location mechanisms, providing expressions that accurately predict average search lengths, which are validated using simulation experiments. Reduction of average search lengths compared to simple random walk searches are found to be very large, even in the face of high network volatility. We also study the cost of the mechanisms, focusing on the overhead implied by the periodic recomputation of partial walks to refresh the information on resources, concluding that the proposed mechanisms behave efficiently and robustly in dynamic networks.Comment: 39 pages, 25 figure

Synthesis of IAN-type N,N-Ligands via Dynamic Kinetic Asymmetric Buchwald-Hartwig Amination

The Pd-catalyzed coupling of racemic heterobiaryl bromides, triflates, or nonaflates with aryl/alkyl primary amines using QUINAP as the ligand provides the corresponding axially chiral heterobiaryl amines with excellent yields and enantioselectivities. Reactivity and structural studies of neutral and cationic oxidative addition intermediates support a dynamic kinetic asymmetric amination mechanism based on the labilization of the stereogenic axis in the latter and suggest that coordination of the amine to the Pd center is the stereodetermining step.Ministerio de Ciencia e Innovación CTQ2013-48164-C2-1-P, CTQ2013-48164-C2-2-P, RYC-2013-12585 for A.R.European FEDER FundsJunta de Andalucía 2012/FQM 1078