Byung-Hyun Moon

Implementation of Energy Efficient LDPC Code for Wireless Sensor Node

The energy efficiency of error control scheme is very important because of the strict energy constraints of wireless sensor networks. Wireless sensor node requires simple error control schemes because of the low complexity request of sensor nodes. Automatic repeat request(ARQ) and forward error correction(FEC) are the key error control strategies in wireless sensor networks. In this paper, we implemented the efficient QC-LDPC encoder which does not require matrix inversion to improve the complexity of the encoder. It is shown that the efficient QC-LDPC code obtained 17.9% and 36% gain respectively in the mean number of transmission for the transmission power of -19.2dBm and -25dBm.

Development of Simple Korean Character Inputting Embedded System for the Severely Disabled

Recently, electronic systems with various character input systems for information representation and delivery. Character input systems for the Korean language such as mobile phone has 12 or more input buttons. In this paper, we developed Korean language input system with 5 input buttons and 2 function buttons for the severely disabled. The inputting system typing sequence resembles Korean consonant and vowel. This system is not only easy to use by the handicapped, but also simple for children and foreigner to learn Korean language.

Enhancement of recognition rate for large quantity documents in gate environment

In this research, it examined the large quantity document recognition in gate environment . Commercial tag with the best stable performance in documents environment have been chosen and the tag position in a document has also been carefully decided via extensive experiments. The gate has been made to achieve the best recognition performance and easy adjustment of the position of reader antennas with inserted Aluminum Profile in the gate. The number of the reader antennas has been doubled with power dividers to get rid of the shadow zones. Reader antennas have been shielded with metals to minimize interference. Moreover, we have developed a tag monitoring program for the optimization of reader antennapsilas position. It can distinguish the shadow zones and the weak tags. As a result of this research, we could recognize over 300 documents stably for the recognition of large quantity of documents.