A Note on Tsallis Holographic Dark Energy

We explore the effects of considering various infrared (IR) cutoffs, including the particle horizon, Ricci horizon and Granda-Oliveros (GO) cutoffs, on the properties of Tsallis holographic dark energy (THDE) model, proposed inspired by Tsallis generalized entropy formalism \cite{THDE}. Interestingly enough, we find that for the particle horizon as IR cutoff, the obtained THDE model can describe the accelerated universe. This is in contrast to the usual HDE model which cannot lead to an accelerated universe, if one consider the particle horizon as IR cutoff. We also investigate the cosmological consequences of THDE under the assumption of a mutual interaction between the dark sectors of the Universe. It is shown that the evolution history of the Universe can be described by these IR cutoffs and thus the current cosmic acceleration can also been realized. The sound instability of THDE models for each cutoff are also explored, separately.Comment: 12 pages, 31 figure

Future broadband access network challenges

Copyright @ 2010 IEEEThe optical and wireless communication systems convergence will activate the potential capacity of photonic technology for providing the expected growth in interactive video, voice communication and data traffic services that are cost effective and a green communication service. The last decade growth of the broadband internet projects the number of active users will grow to over 2 billion globally by the end of 2014. Enabling the abandoned capacity of photonic signal processing is the promising solution for seamless transportation of the future consumer traffic demand. In this paper, the future traffic growth of the internet, wireless worldwide subscribers, and the end-users during the last and next decades is investigated. The challenges of the traditional access networks and Radio over Fiber solution are presented

All photonic analogue to digital and digital to analogue conversion techniques for digital radio over fibre system applications

Copyright @ 2011 IEEEWideband electronic analogue to digital conversion (ADC) systems have critical problems encountered in high-frequency broadband communication systems that the recent electronic ADCs (EADC) have experienced those such as uncertainty of sampling time. In this paper, an all photonic sampling and quantization ADC and photonic digital to analogue conversion system with six effective number of bits (ENOB) is designed. By using this photonic ADC (PADC), a novel digital radio over fibre link for wireless radio frequency (RF) signal transportation over 20 Km single mode fibre has been designed whose performance is investigated in this paper. In the digital radio over fibre, the dynamic range is independent of the fibre length

Digital radio over fibre for future broadband wireless access network solution

Copyright @ 2010 IEEEDigital systems are more flexible and environment-process-tolerant than analogue systems. They are more reliable and robust against cross-talk, interference and channel noises, and are capable of covering higher dynamic range than analogue systems. Wideband electronic analogue to digital conversion (ADC) systems have critical problems encountered in high-frequency broadband communication systems that the recent electronic ADCs (EADC) have experienced those such as uncertainty of sampling time. In this paper, an 80Gigasample/s all photonic sampling and quantization ADC and photonic digital to analogue conversion system with six effective number of bits (ENOB) is designed. By using this Photonic ADC (PADC), a digital radio over fibre link for wireless radio frequency (RF) signal transportation over 50 km single mode fibre has been designed whose performance is investigated in this paper

Full duplex 60 GHz millimeter wave transmission over multi-mode fiber

Copyright @ 2010 IEEENew wireless subscribers are signing up at an increasing demand of more capacity for ultra-high data rate transfers at speeds more than 1 Gbps, while the radio spectrum is limited. Millimeter wave communication system offers a unique way to resolve these problems. In this paper, the performance of a full duplex transportation system is reported for 1.5 Km of multi-mode fiber length for a sample 10 Gbit/s pseudo random sequence data, with quadrature amplitude modulation mapping and orthogonal frequency division multiplexing modulation with 60 GHz RF and coherent 1550 nm optical carrier. The analysis and simulation results show that the system's quality of service depends on nonlinearity of electro optical modulator, dispersion and signal attenuation impairment of the multi-mode fiber cable