Unlike terrestrial radio communication, airborne Internet access services are still based on satellite communication systems, which use single carrier FDMA/TDMA access interfaces. To maximize the resource utilization and acquire maximum benefit of the services, it would be natural to apply OFDMA/SCFDMA based terrestrial systems like LTE for the satellite-airborne communication systems. However, these systems were originally designed for short delay conditions in microseconds and have difficulties under the very long delay between satellite and airplanes. In this paper, we propose a simple and effective way of resource allocation for LTE uplink SCFDMA which would be applicable to airborne-satellite communication systems.

This letter aims to address the problem of wireless resource constraints in wireless robotic networks to enable stable acquisition of map information for a number of robots. In order to reduce wireless resource consumption, we propose a two-step data acquisition scheme for robots. In the proposed scheme, only a few robots directly download map information from the server, most robots acquire map information by means of local data sharing with short range communications among nearby robots. A distributed clustering scheme is utilized to decide which nodes download map information from the server. Evaluation results show that the proposed scheme highly reduces wireless resource consumption, especially when there are many service robots.

Cascaded long period fiber gratings (LPFGs) fabricated with heat-shrinkable tube, screw, and single-mode fiber are proposed herein that employ a thin confinement layer on the bare fiber. The transmittance of a proposed cascaded-LPFG is theoretically and experimentally investigated regarding the cladding mode loss. By employing the confinement layer on the cladding of the proposed LPFGs, mode recoupling between core and cladding modes is successfully induced. Our cascaded-LPFG has potential application for the simple and low-cost optical filters and for the optical sensors monitoring vibration, refractive index, or temperature.

High-speed data transmission over electric wiring in a VLSI system is achieved by employing equalization circuitry for waveform shaping. This letter presents a novel transmitter that incorporates waveform shaping techniques especially for multi-valued signaling. The combination of digital and analog equalizers and adjustment of the digital parameter can improve the waveform distortion of rising and falling edges. Simulation and experimental results of multi-valued data transmission are shown to demonstrate the feasibility of the proposed transmitter, which is capable of controlling the received waveforms flexibly and improve the signal integrity.

This paper deals with consensus control for multi-agent systems over CSMA/CA(Carrier Sense Multiple Access with Collision Avoidance)-based wireless networks. In consensus control, the number of agents within the communication range changes with time according to the movement of the agents and affects the packet collision rate. In this paper, we propose a new method to reduce the packet collision rate considering consensus dynamics of the agents. In the proposed method, each agent distributedly estimates the priority of its own position information on the basis of position information received from its adjacent agents and then adjusts transmission probability according to the estimated priority. Simulation results show that the proposed method improves the control quality.

The number of participants in the McEliece-Sarwate strongly secure ramp secret sharing scheme is at most q − L, where q is the size of each share and L is the number of symbols in the secret. We propose another construction of strongly secure ramp secret sharing that can support q participants also based on the Reed-Solomon codes.