Akihisa Yokoyama

Implementation of Multi-channel Modern and Multi-channel Radio Broadcast Receiver on Reconfigurable Packet Routing-oriented Signal Processing Platform (RPPP)

A new architecture for a signal processing platform suited for flexible software defined radio called RPPP has been proposed by the authors. In this architecture, the platform can change its functionality clock by clock and multiple function radio equipment is realized flexibility. This paper describes two implementations of SDR using RPPP. One is the receiver for DSRC which can handle two different standards of DSRC. The other is a multi-channel FM broadcast receiver. Through the implementation, efficiency of logic usage and the performance of the radio equipment are evaluated.

Implementation of multi-channel modem for DSRC system on signal processing platform for software defined radio

We previously proposed an architecture for software defined radio called the reconfigurable packet routing-oriented signal processing platform (RPPP). This architecture was suited to wireless signal processing applications, which require radio functions to be selected in real time depending on the transmitted signal. A number of radio standards are used in DSRC systems for vehicle communication and vehicle equipment is required to transmit and receive the radio signals used on each particular occasion. An implementation of RPPP is described in this paper that enables the dynamic handling of two ARIB standards for DSRC. After an explanation of the basic architecture and an analysis of RPPP, the implementation of a reconfigurable DSRC transceiver for ASK and π/4 shift-QPSK is described. The implementation is then discussed, evaluated in terms of the number of logic units needed. We concluded that our platform is 27.6% more efficient in utilizing logic than that achieved with fixed design.

Smart charging system for PEV based on SEP 2.0 and SAE standards

In this paper, we consider smart charging systems for plug-in electric vehicles. We formulate an optimization problem of smart charging scheduling in which the charging schedule is optimized so that it supplies sufficient electricity for the next trip and also minimizes the charging cost under given time-of-use (TOU) rate structures while it follows demand response (DR) events requested by a utility, and we also present an algorithm to solve the optimization problem. To validate the effectiveness of our smart charging system, we first developed and implemented a smart charging system using SEP 2.0 and SAE J2836/2847/J2931 and conducted demonstration experiments in which a total of 10 customers of Duke Energy regularly used our developed system for approximately one year with simulated TOU rate structures and DR events. We also present the results of the experiments for our developed smart charging system to show the cost benefits for users without forcing their patience and the impact on peak demand shift by the user-friendly system.

Grouped Interference Alignment in Inter-Vehicle Communications

This paper investigates the application of interference alignment (IA) to inter-vehicle communications for further performance improvement. In conventional IA in the spatial domain, the number of antennas of each terminal limits the number of terminals, and therefore the sum rate performance is upper-bounded. This paper shows that when IA is applied to inter-vehicle communications at an intersection, it is possible to exceed the sum rate of the conventional IA by taking into account the effect of path loss. To this end, we consider multiple-input multiple-output interference channels with two IA groups, where all interference signals from the same group are aligned at each receiver by virtue of IA, but interference signals from the other group are not. Simulation results show that two IA groups can geographically co-exist by utilizing high propagation loss at a corner of the intersection to mitigate inter-group interference, and thus the achievable sum rate can be significantly improved, compared with that of single- group IA.

A Reconfigurable Packet Routing-Oriented Signal Processing Platform

In this paper we propose a new reconfigurable signal processing platform for SDR, having capability to change its processing parameters dynamically. On our proposed platform, while the wiring and processing scheme remain fixed, processing parameters and connections between processing modules together with the associated dataflow can be changed. We also demonstrate that our proposed signal processing platform has the new ability of easily composing new signal processing models dynamically, simultaneously with other tasks, and attaining high efficiency of logic usage.