Jae-Hyon Kim

Comparison of DCSK Receiver and Enhanced DCSK Receiver with Synchronization Error

Over the past decade, much research effort has been devoted to the study of communication using chaotic basis functions. Due to the low complexity in hardware implementation and low power consumption in chaotic signal generation, the chaotic signal is one of the possible candidate signals, applicable to both low rate ultra-wideband (UWB) systems and sensor networks. Among the modulation schemes using the chaotic signal, differential chaos shift keying (DCSK) is a robust non-coherent technique with respect to the implementation issue. However, inter symbol interference (ISI) can induce the crucial performance degradation and synchronization error may destroy the orthogonality of the basis functions. Therefore, we present enhanced DCSK scheme and investigate the effect of the synchronization error on the performance by comparison with that of conventional DCSK

A Chaotic UWB System for Home networks

Emerging wireless technologies will play an important role in home network applications. Chaotic UWB technology has several inherent properties that are suited to home networks. In particular, applications have been focused such as low power consumption, low complexity, and low cost. In this paper, we describe the chaotic signal based UWB systems and the optimum sample number to minimize the bit error rate of the chaotic on-off keying. Moreover, we propose new scheme using the optical orthogonal code based chaotic on-off keying in an asynchronous channel for simultaneously operating piconets environment: all users are allowed to transmit their signal at any time, and moreover there is usually no network synchronization or coordinator among users.

WLC18-2: Efficient Low-Complexity Ranging Algorithm for Low Rate UWB Systems

In IEEE 802.15.4a, location awareness is a mandatory function in most applications. The exact location-finding highly depends on the ranging accuracy. In order to reach the higher ranging accuracy, less than 1 meter distance measurement error, most of the previous ranging algorithms require the extremely high sampling rate for ranging process. However, it should increase the hardware complexity and implementation cost. In this respect, we present a low-complex and cost-efficient ranging algorithm, still satisfying the reliably high ranging accuracy comparing with the previous works. This novel scheme is based on utilizing two clock pulses with a slightly different frequency in one device to measure the relative distance between two devices. The simulation results show the effect of possible several factors on the ranging accuracy.