In this paper, we investigate a spinning black ring and a charged black ring in the context of gravity's rainbow. By incorporating rainbow functions proposed by Amelino-Camelia, et al. in ...arXiv:hep-th/9605211, arXiv:0806.0339v2 in the metric of the black rings, a considerable modification happens to their thermodynamical properties. We calculate corrections to the temperature, entropy and heat capacity of the black rings. These calculations demonstrate that the behavior of Hawking radiation changes considerably near the Planck scale in gravity's rainbow, where it is shown that black rings do not evaporate completely and a remnant is left as the black rings evaporate down to Planck scale.
Mobile WiMAX is a new promising technology based on IEEE 802.16-2005 that supports high-speed, broadband fixed and mobile services through using orthogonal frequency division multiple access (OFDMA). ...In mobile communications, channel estimation is important for system performance, but at the same time it is very crucial when the fading channel is fast time-varying. In this paper, a cluster-based downlink channel estimation and tracking in mobile WiMAX is evaluated based on least square (LS) methods. Interpolation between channel estimates at pilots is carried out both over frequency and time to compensate between high data transfer rate as well as efficient channel estimation. Simulation results in terms of mean square error (MSE) and bit error rate (BER) show that channel estimation over two OFDM symbols exhibits better performance compared to that of single OFDM symbol even at high Doppler frequencies.
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