Pub Date : 2008-04-22DOI: 10.1109/ICACT.2008.4493781
Min Lee, S. Oh
In this paper, we deal with an optimum per-user power allocation problem in terms of the sum capacity in multiuser multiple input multiple output (MU-MIMO) downlink systems when the minimum mean square error (MMSE) scheme has been used for multiuser preceding. However, MMSE preceding allows some inter-user interference. In this paper, we propose a modified iterative water-filling (MIWF) algorithm with per-iteration power normalization (PIPN) in multiuser MMSE-precoded MIMO systems. In the proposed algorithm, power levels for respectacle users are re-adjusted prior to the consecutive iteration, so that the total transmit power constraint should be satisfied. This normalization can reduce greatly the number of iterations for the iterative water-filling process since the inter-user interference terms at every iteration can be computed more accurately without performance degradation. From computer simulations and complexity analyses, we see that the proposed algorithm has lower complexity but with the same capacity as compared with the original MIWF algorithm.
{"title":"A Modified Iterative Water-filling Algorithm with Per-iteration Power Normalization in Multiuser MMSE-Precoded MIMO Systems","authors":"Min Lee, S. Oh","doi":"10.1109/ICACT.2008.4493781","DOIUrl":"https://doi.org/10.1109/ICACT.2008.4493781","url":null,"abstract":"In this paper, we deal with an optimum per-user power allocation problem in terms of the sum capacity in multiuser multiple input multiple output (MU-MIMO) downlink systems when the minimum mean square error (MMSE) scheme has been used for multiuser preceding. However, MMSE preceding allows some inter-user interference. In this paper, we propose a modified iterative water-filling (MIWF) algorithm with per-iteration power normalization (PIPN) in multiuser MMSE-precoded MIMO systems. In the proposed algorithm, power levels for respectacle users are re-adjusted prior to the consecutive iteration, so that the total transmit power constraint should be satisfied. This normalization can reduce greatly the number of iterations for the iterative water-filling process since the inter-user interference terms at every iteration can be computed more accurately without performance degradation. From computer simulations and complexity analyses, we see that the proposed algorithm has lower complexity but with the same capacity as compared with the original MIWF algorithm.","PeriodicalId":448615,"journal":{"name":"2008 10th International Conference on Advanced Communication Technology","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133679116","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}
Pub Date : 2008-04-22DOI: 10.1109/ICACT.2008.4493881
Yun-A Shim, Jeong-Seon Lee, Sek-Kyun Han, Sang-Gug Lee
A fully integrated RF front-end receiver for 3-5 GHz UWB application is reported. Low noise amplifier (LNA) adopts wide simultaneous noise and input matching technique to get better noise performance. Folded double balanced down conversion mixer is integrated with LNA implemented by 0.13 mum CMOS technology. Measured noise figure (NF) of each band (3432, 3960, and 4488 MHz) is 2.5, 3.3, and 4.2 dB at 100 MHz IF, respectively. Voltage conversion gain is measured as 19.4 dB to 23.5 dB. At the maximum gain band, -20 dBm IIP3 and -28 dBm PldB are measured. The total current is 14 mA from a 1.5 V supply.
{"title":"Low Noise RF Front-End Receiver for 3~5 GHz UWB","authors":"Yun-A Shim, Jeong-Seon Lee, Sek-Kyun Han, Sang-Gug Lee","doi":"10.1109/ICACT.2008.4493881","DOIUrl":"https://doi.org/10.1109/ICACT.2008.4493881","url":null,"abstract":"A fully integrated RF front-end receiver for 3-5 GHz UWB application is reported. Low noise amplifier (LNA) adopts wide simultaneous noise and input matching technique to get better noise performance. Folded double balanced down conversion mixer is integrated with LNA implemented by 0.13 mum CMOS technology. Measured noise figure (NF) of each band (3432, 3960, and 4488 MHz) is 2.5, 3.3, and 4.2 dB at 100 MHz IF, respectively. Voltage conversion gain is measured as 19.4 dB to 23.5 dB. At the maximum gain band, -20 dBm IIP3 and -28 dBm PldB are measured. The total current is 14 mA from a 1.5 V supply.","PeriodicalId":448615,"journal":{"name":"2008 10th International Conference on Advanced Communication Technology","volume":" 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133121393","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}
Pub Date : 2008-04-22DOI: 10.1109/ICACT.2008.4493907
Ki Tae Kim, S. Oh
We propose an efficient deployment scenario for cognitive ad-hoc networking under a cellular network with a pre-defined interference temperature limit (ITL). Using this scenario, a cellular radio spectrum can be reused efficiently without disturbing the existing cellular network. It uses a relaxed ITL concept in which the pre-defined ITL is satisfied at the target receiver only instead of all around the cellular service coverage. In this scenario, a cognitive radio (CR)-enabled secondary user (also, called as a cognitive ad-hoc user), equipped with the cellular signal strength monitoring device measures the pathloss from the nearest cellular base station (CBS) (also, called as the target CBS) in a cellular downlink channel. Then, using the measured pathloss, each secondary user computes its allowable maximum transmit power level (AMTPL) for a cellular uplink channel. In this scenario, secondary users farther from the target CBS can transmit more power than nearer users can do, thus making the cellular uplink resource reused more efficiently. Therefore, the proposed scenario can reduce the routing overhead and associated delay, and the infrastructure cost because this secondary user power flexibility can decrease the number of required nodes for cognitive ad-hoc networking, or can increase the utilization efficiency of the cellular radio spectrum.
{"title":"Cognitive Ad-hoc Networks under a Cellular Network with an Interference Temperature Limit","authors":"Ki Tae Kim, S. Oh","doi":"10.1109/ICACT.2008.4493907","DOIUrl":"https://doi.org/10.1109/ICACT.2008.4493907","url":null,"abstract":"We propose an efficient deployment scenario for cognitive ad-hoc networking under a cellular network with a pre-defined interference temperature limit (ITL). Using this scenario, a cellular radio spectrum can be reused efficiently without disturbing the existing cellular network. It uses a relaxed ITL concept in which the pre-defined ITL is satisfied at the target receiver only instead of all around the cellular service coverage. In this scenario, a cognitive radio (CR)-enabled secondary user (also, called as a cognitive ad-hoc user), equipped with the cellular signal strength monitoring device measures the pathloss from the nearest cellular base station (CBS) (also, called as the target CBS) in a cellular downlink channel. Then, using the measured pathloss, each secondary user computes its allowable maximum transmit power level (AMTPL) for a cellular uplink channel. In this scenario, secondary users farther from the target CBS can transmit more power than nearer users can do, thus making the cellular uplink resource reused more efficiently. Therefore, the proposed scenario can reduce the routing overhead and associated delay, and the infrastructure cost because this secondary user power flexibility can decrease the number of required nodes for cognitive ad-hoc networking, or can increase the utilization efficiency of the cellular radio spectrum.","PeriodicalId":448615,"journal":{"name":"2008 10th International Conference on Advanced Communication Technology","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128850255","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}
Pub Date : 2008-04-22DOI: 10.1109/ICACT.2008.4493835
L. Pan, Yueh Shun Li, Tung-ying Lee
Recently, many kinds of wireless communication protocols are meaning for research. In the structure of ad hoc wireless networks, there are many researches discuss how to use better scheme for saving power. On the other hand, some researches proposed differs routing protocol for speed up routing discovery in ad hoc networks. Furthermore, even achieve the goal above, it requires reduce loading of networks simultaneously. Therefore, we propose a novel cluster routing protocol with power balance scheme in ad hoc networks, calls NCRPB. By using NCRPB scheme, it can reduce the loading of networks, power depletion effective, and increase life time of nodes and networks.
{"title":"A Novel Cluster Routing Protocol with Power Balance in Ad Hoc Networks","authors":"L. Pan, Yueh Shun Li, Tung-ying Lee","doi":"10.1109/ICACT.2008.4493835","DOIUrl":"https://doi.org/10.1109/ICACT.2008.4493835","url":null,"abstract":"Recently, many kinds of wireless communication protocols are meaning for research. In the structure of ad hoc wireless networks, there are many researches discuss how to use better scheme for saving power. On the other hand, some researches proposed differs routing protocol for speed up routing discovery in ad hoc networks. Furthermore, even achieve the goal above, it requires reduce loading of networks simultaneously. Therefore, we propose a novel cluster routing protocol with power balance scheme in ad hoc networks, calls NCRPB. By using NCRPB scheme, it can reduce the loading of networks, power depletion effective, and increase life time of nodes and networks.","PeriodicalId":448615,"journal":{"name":"2008 10th International Conference on Advanced Communication Technology","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127773776","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}
Pub Date : 2008-04-22DOI: 10.1109/ICACT.2008.4493873
Joo-Kwan Lee, Youngmin Kim, Sunghwan Sohn, Jaemoung Kim
Cognitive radio is an advanced technology for efficient utilization of under-utilized spectrum since it is able to sense the available spectrum and use empty frequency bands if there is no use of primary user. These sensing observations are forwarded a cognitive radio base-station through fading channels, the sensing performance will be severely degraded. In order to mitigate this effect, weighted-cooperative sensing was considered to be a promising way in our previous work, which combines the sensing result of each CR user to improve the performance. However, in practical, the probability of detection is unavailable to calculate in each user. In this paper, we propose a weighted-cooperative sensing scheme using clustering to improve the performance and to overcome the critical problem. Numerical results show that the sensing performance is improved obviously as opposed to conventional spectrum scheme.
{"title":"Weighted-Cooperative Spectrum Sensing Scheme using Clustering in Cognitive Radio Systems","authors":"Joo-Kwan Lee, Youngmin Kim, Sunghwan Sohn, Jaemoung Kim","doi":"10.1109/ICACT.2008.4493873","DOIUrl":"https://doi.org/10.1109/ICACT.2008.4493873","url":null,"abstract":"Cognitive radio is an advanced technology for efficient utilization of under-utilized spectrum since it is able to sense the available spectrum and use empty frequency bands if there is no use of primary user. These sensing observations are forwarded a cognitive radio base-station through fading channels, the sensing performance will be severely degraded. In order to mitigate this effect, weighted-cooperative sensing was considered to be a promising way in our previous work, which combines the sensing result of each CR user to improve the performance. However, in practical, the probability of detection is unavailable to calculate in each user. In this paper, we propose a weighted-cooperative sensing scheme using clustering to improve the performance and to overcome the critical problem. Numerical results show that the sensing performance is improved obviously as opposed to conventional spectrum scheme.","PeriodicalId":448615,"journal":{"name":"2008 10th International Conference on Advanced Communication Technology","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131655309","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}
Pub Date : 2008-04-22DOI: 10.1109/ICACT.2008.4493911
M. B. Bin Ismail, A. Fathi, A. Boud, W. Nurdiana, W. Ibrahim
Wireless local area network (WLAN) is developed to complement the wired network. Various standards for WLAN exist, but the most common standards are IEEE 802.11b and 802.11g. Since WLAN provides the mobility to the network users, there was some interesting in determine the location for the users. IEEE 802.11 standards did not support the location services. This paper tries to implement the three methods to add location services to the WLAN. The three main localization techniques adopted were close access points (AP), propagation method and radio map. The signal from three access points were monitored using software developed in Java and Matlab. The experiments were taken in real time at UKM Mercator Office and its multimedia laboratory. In general, the real time AP location was successfully determined with reasonable error.
{"title":"Implementation of Location Determination in a Wireless Local Area Network (WLAN) Environment","authors":"M. B. Bin Ismail, A. Fathi, A. Boud, W. Nurdiana, W. Ibrahim","doi":"10.1109/ICACT.2008.4493911","DOIUrl":"https://doi.org/10.1109/ICACT.2008.4493911","url":null,"abstract":"Wireless local area network (WLAN) is developed to complement the wired network. Various standards for WLAN exist, but the most common standards are IEEE 802.11b and 802.11g. Since WLAN provides the mobility to the network users, there was some interesting in determine the location for the users. IEEE 802.11 standards did not support the location services. This paper tries to implement the three methods to add location services to the WLAN. The three main localization techniques adopted were close access points (AP), propagation method and radio map. The signal from three access points were monitored using software developed in Java and Matlab. The experiments were taken in real time at UKM Mercator Office and its multimedia laboratory. In general, the real time AP location was successfully determined with reasonable error.","PeriodicalId":448615,"journal":{"name":"2008 10th International Conference on Advanced Communication Technology","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115703080","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}
Pub Date : 2008-04-22DOI: 10.1109/ICACT.2008.4493847
Kuo-shien Huang, Shun-ming Tang
RFID is in great demand, recently. Though implementation of RFID is not difficult and RFID technology is more and more maturity, but still has many failure cases. This is because RFID has many limitations in the application. To solve these limitations, planned a strategy of business is first necessary step when decided to use RFID. Second step was designed RFID applications' hardware and software architecture. This paper considered a strategy and a process in bike renting, and then designed a structure of RFID. Finally provide an approach to reference when deploy RFID in the enterprise business
{"title":"RFID Applications Strategy and Deployment in Bike Renting System","authors":"Kuo-shien Huang, Shun-ming Tang","doi":"10.1109/ICACT.2008.4493847","DOIUrl":"https://doi.org/10.1109/ICACT.2008.4493847","url":null,"abstract":"RFID is in great demand, recently. Though implementation of RFID is not difficult and RFID technology is more and more maturity, but still has many failure cases. This is because RFID has many limitations in the application. To solve these limitations, planned a strategy of business is first necessary step when decided to use RFID. Second step was designed RFID applications' hardware and software architecture. This paper considered a strategy and a process in bike renting, and then designed a structure of RFID. Finally provide an approach to reference when deploy RFID in the enterprise business","PeriodicalId":448615,"journal":{"name":"2008 10th International Conference on Advanced Communication Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124372356","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}
Pub Date : 2008-04-22DOI: 10.1109/ICACT.2008.4493795
Seungsik Lee, B. Park, Seunghyun Jang, Sangsung Choi
This paper compares performance of three transmitter/receiver (T/RX) switch structures, which can be included as UWB RF transceiver. They are designed using complementary metal-oxide semiconductor (CMOS) 0.13 um technology and simulated each structure. They can be operated from 3 to 5 GHz and package model are applied for chip on board(COB) test. They have 1.8 dB insertion loss and more than 30 dB isolation at 5 GHz.
{"title":"The Comparison of T/RX Switch Performance for UWB Communication","authors":"Seungsik Lee, B. Park, Seunghyun Jang, Sangsung Choi","doi":"10.1109/ICACT.2008.4493795","DOIUrl":"https://doi.org/10.1109/ICACT.2008.4493795","url":null,"abstract":"This paper compares performance of three transmitter/receiver (T/RX) switch structures, which can be included as UWB RF transceiver. They are designed using complementary metal-oxide semiconductor (CMOS) 0.13 um technology and simulated each structure. They can be operated from 3 to 5 GHz and package model are applied for chip on board(COB) test. They have 1.8 dB insertion loss and more than 30 dB isolation at 5 GHz.","PeriodicalId":448615,"journal":{"name":"2008 10th International Conference on Advanced Communication Technology","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114344054","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}
Pub Date : 2008-04-22DOI: 10.1109/ICACT.2008.4493788
Youngtae Han, Hong-Kyu Park
Many literatures related to game and Peer-to-Peer (P2P) applications are focused on the performance enhancement. Few years ago, game applications just use the client and server model. However, today many game applications use the P2P model. Thus, there are many similarities between P2P and game applications over the P2P model. Though, many network providers desire to know the distribution of applications on their networks. These similarities between game and P2P applications make hard to identify each other. Thus, we characterize the differences between game and P2P applications.
{"title":"Distinctive Traffic Characteristics of Pure and Game P2P Applications","authors":"Youngtae Han, Hong-Kyu Park","doi":"10.1109/ICACT.2008.4493788","DOIUrl":"https://doi.org/10.1109/ICACT.2008.4493788","url":null,"abstract":"Many literatures related to game and Peer-to-Peer (P2P) applications are focused on the performance enhancement. Few years ago, game applications just use the client and server model. However, today many game applications use the P2P model. Thus, there are many similarities between P2P and game applications over the P2P model. Though, many network providers desire to know the distribution of applications on their networks. These similarities between game and P2P applications make hard to identify each other. Thus, we characterize the differences between game and P2P applications.","PeriodicalId":448615,"journal":{"name":"2008 10th International Conference on Advanced Communication Technology","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114433882","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}
Pub Date : 2008-04-22DOI: 10.1109/ICACT.2008.4493811
Mihui Kim, K. Chae
As the importance of sensor networks for the realization of ubiquitous world is recognized, the various aspects research for static sensor networks, that does not support the mobility of node, is underway. Medical sensor network (MSN) assuming the mobility of node takes notice as one of the highlight USN applications, but the research on the security issue for the environments is not enough even though the issue is the most important point for the successful deployment. Thus, in this paper we propose an adaptive authentication mechanism taking consideration in the tradeoff between processing speed and the degree of security strength. Using threshold secret sharing, our authentication gives the proper reputation to sensor nodes according to their behavior pattern. Thus if a sensor node has the best reputation and its sensing information is urgent, then the sink node processes the sensing information at first and performs post-authentication. Our analytical results show that our authentication provides the efficient to MSN even in the severe node traffic.
{"title":"Adaptive Authentication Mechanism using Node Reputation on Mobile Medical Sensor Networks","authors":"Mihui Kim, K. Chae","doi":"10.1109/ICACT.2008.4493811","DOIUrl":"https://doi.org/10.1109/ICACT.2008.4493811","url":null,"abstract":"As the importance of sensor networks for the realization of ubiquitous world is recognized, the various aspects research for static sensor networks, that does not support the mobility of node, is underway. Medical sensor network (MSN) assuming the mobility of node takes notice as one of the highlight USN applications, but the research on the security issue for the environments is not enough even though the issue is the most important point for the successful deployment. Thus, in this paper we propose an adaptive authentication mechanism taking consideration in the tradeoff between processing speed and the degree of security strength. Using threshold secret sharing, our authentication gives the proper reputation to sensor nodes according to their behavior pattern. Thus if a sensor node has the best reputation and its sensing information is urgent, then the sink node processes the sensing information at first and performs post-authentication. Our analytical results show that our authentication provides the efficient to MSN even in the severe node traffic.","PeriodicalId":448615,"journal":{"name":"2008 10th International Conference on Advanced Communication Technology","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114736248","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}
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