{"title":"Adaptive MIMO switching of 2×2 MIMO system for WiMAX technology","authors":"P. Khakhai, P. Uthansakul, M. Uthansakul","doi":"10.1109/COMCOMAP.2012.6154879","DOIUrl":"https://doi.org/10.1109/COMCOMAP.2012.6154879","url":null,"abstract":"The growth in traffic volume and the increase in many new services have forced the change of wireless configuration and transmission schemes. WiMAX (Worldwide Interoperability for Microwave Access) system is considered as one technology to ground the broadband access facility by providing a variety of modulation and transmission schemes. MIMO (Multiple Input Multiple Output) technique is employed in WiMAX system to provide a higher data rate and improve a spectral efficiency. The MIMO schemes based on WiMAX standard are determined by various choices of either space-time coding or spatial multiplexing in which each choice offers a different system performance. In this paper, the adaptive MIMO switching has been proposed to maintain the best BER (Bit Error Rate) efficiency of data transmission among various choices of MIMO schemes in WiMAX system. The results reveal that the proposed system achieves a significant improvement when using adaptive MIMO switching instead of using only either spatial multiplexing or space-time coding.","PeriodicalId":281865,"journal":{"name":"2012 Computing, Communications and Applications Conference","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121127719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Developing a mobile phone-based fall detection system on Android platform","authors":"Shih-Hau Fang, Yi-Chung Liang, Kuan-Ming Chiu","doi":"10.1109/COMCOMAP.2012.6154019","DOIUrl":"https://doi.org/10.1109/COMCOMAP.2012.6154019","url":null,"abstract":"Since todays smartphones are programmable and embed various sensors, these phones have the potential to change the way how healthcare is delivered. Fall detection is definitely one of the possibilities. Injuries due to falls are dangerous, especially for elderly people, diminishing the quality of life or even resulting in death. This study presents the implementation of a fall detection prototype for the Android-based platform. The proposed system has three components: sensing the accelerometer data from the mobile embedded sensors, learning the relationship between the fall behavior and the collected data, and alerting preconfigured contacts through message while detecting fall. We adopt different fall detection algorithms and conduct various experiments to evaluate performance. The results show that the proposed system can recognize the fall from human activities, such as sitting, walking and standing, with 72.22% sensitivity and 73.78% specificity. The experiment also investigates the impact of different locations where the phone attached. In addition, this study further analyzes the trade-off between sensitivity and specificity and discusses the additional power consumption of the devices.","PeriodicalId":281865,"journal":{"name":"2012 Computing, Communications and Applications Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127178678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}