Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Engineering
Modulation Identification And Carrier Recovery System For Adaptive Modulation In Satellite Communications, Kenta Umebayashi, Robert H. Morelos-Zaragoza, Ryuji Kohno
Modulation Identification And Carrier Recovery System For Adaptive Modulation In Satellite Communications, Kenta Umebayashi, Robert H. Morelos-Zaragoza, Ryuji Kohno
Faculty Publications
We introduce the modulation identification technique implementing the multimode phase locked loop (PLL) in the satellite communication using adaptive modulation scheme which is a countermeasure against the rain attenuation. In the multimode PLL, phase lock detectors (PLDs) are used for not only phase lock, but also modulation identification. We present the sub-optimized design of the PLDs for modulation identification with respect to the throughput and show the validity of sub-optimization. In addition, by the comparison between the multimode PLL and conventional scheme in ISDB-S, we present the effectivity of the multimode PLL.
A Suboptimal Receiver With Turbo Block Coding For Ultra-Wideband Communications, Robert H. Morelos-Zaragoza, Timothy Becker, Sim Aquino
A Suboptimal Receiver With Turbo Block Coding For Ultra-Wideband Communications, Robert H. Morelos-Zaragoza, Timothy Becker, Sim Aquino
Faculty Publications
In this paper, the performance of adaptive equalization and turbo product coding is investigated for pulse-based UWB communications in short-range indoor environments. The sensitivity of adaptive LMS linear and nonlinear (decision-feedback) equalizers with respect to the number of training symbols and number of taps is considered. To reduce the error performance variation with respect to changing channel conditions, a turbo product code (TPC) with two component (31,26,3) Hamming codes is proposed. We report simulation results showing that channel coding not only improves error performance, but also reduces significantly the sensitivity of UWB systems in short-range indoor wireless communications.