Pub Date : 2011-10-17DOI: 10.1109/GMC.2011.6103915
Minglei Shen
This paper introduces a design method of K Band up-converter in microwave transmitter module. Coupling loop single balanced structure is applied in the up-converter. This up-converter has simple structure and good performance, which conversion loss is less than 8dB and the isolation of signal to LO is more than 30dB.
{"title":"Design of microwave single balanced up-converter","authors":"Minglei Shen","doi":"10.1109/GMC.2011.6103915","DOIUrl":"https://doi.org/10.1109/GMC.2011.6103915","url":null,"abstract":"This paper introduces a design method of K Band up-converter in microwave transmitter module. Coupling loop single balanced structure is applied in the up-converter. This up-converter has simple structure and good performance, which conversion loss is less than 8dB and the isolation of signal to LO is more than 30dB.","PeriodicalId":435824,"journal":{"name":"2011 Global Mobile Congress","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127496093","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 : 2011-10-17DOI: 10.1109/GMC.2011.6103913
Jianwu Zhang, Huan Yan, J. Bao
This paper proposes a new scheme of the rate compatible low-density parity-check (RC-LDPC) coded single carrier-frequency domain equalization (SC-FDE) system where RC-LDPC codes are combined with SC-FDE modulations. To construct a class of different RC-LDPC codes, we take advantage of a base matrix constructed by the progressive edge growth (PEG) algorithm. A special code matrix structure is used and modified to meet requirements of the different code rate. In addition, a pseudorandom sequence instead of traditional cyclic prefix (CP) is proposed to estimate the channel noise variance for LDPC decoding. The simulation results show that the modified RC-LDPC codes have better performance than that of current method and the RC-LDPC coded SC-FDE system obtains better performance compared with uncoded SC-FDE system.
{"title":"Design of RC-LDPC codes and its application in codes SC-FDE systems","authors":"Jianwu Zhang, Huan Yan, J. Bao","doi":"10.1109/GMC.2011.6103913","DOIUrl":"https://doi.org/10.1109/GMC.2011.6103913","url":null,"abstract":"This paper proposes a new scheme of the rate compatible low-density parity-check (RC-LDPC) coded single carrier-frequency domain equalization (SC-FDE) system where RC-LDPC codes are combined with SC-FDE modulations. To construct a class of different RC-LDPC codes, we take advantage of a base matrix constructed by the progressive edge growth (PEG) algorithm. A special code matrix structure is used and modified to meet requirements of the different code rate. In addition, a pseudorandom sequence instead of traditional cyclic prefix (CP) is proposed to estimate the channel noise variance for LDPC decoding. The simulation results show that the modified RC-LDPC codes have better performance than that of current method and the RC-LDPC coded SC-FDE system obtains better performance compared with uncoded SC-FDE system.","PeriodicalId":435824,"journal":{"name":"2011 Global Mobile Congress","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128294553","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 : 2011-10-17DOI: 10.1109/GMC.2011.6103923
Xingjia Zhang, Dongya Shen, Lan Li, Hui-yuan Liu
A frequency reconfigurable antenna for WLAN/WiMAX applications is proposed. Frequency reconfigurable can be achieved by the transform of two PIN diodes switch on the ground slot. The proposed frequency reconfigurable antenna operates in WLAN 2.4 GHz band (2400–2484MHz) and WIMAX 2.5 GHz (2500–2690MHz). When both diodes were disconnected, and operates in WLAN 5.2 GHz (5150–5350MHz) and WIMAX 3.5GHz (3400–3690 MHz)/ 5.5 GHz (5250–5850 MHz) when both diodes were closed. PIN switches on or off can affect antenna's feeding structure, which can solve matching problem caused by change of antenna radiation body structure. In this way, the proposed antenna has good reconfigurable characteristic and high radiation gain.
{"title":"A compact frequency reconfigurable antenna applied to WLAN/WiMAX","authors":"Xingjia Zhang, Dongya Shen, Lan Li, Hui-yuan Liu","doi":"10.1109/GMC.2011.6103923","DOIUrl":"https://doi.org/10.1109/GMC.2011.6103923","url":null,"abstract":"A frequency reconfigurable antenna for WLAN/WiMAX applications is proposed. Frequency reconfigurable can be achieved by the transform of two PIN diodes switch on the ground slot. The proposed frequency reconfigurable antenna operates in WLAN 2.4 GHz band (2400–2484MHz) and WIMAX 2.5 GHz (2500–2690MHz). When both diodes were disconnected, and operates in WLAN 5.2 GHz (5150–5350MHz) and WIMAX 3.5GHz (3400–3690 MHz)/ 5.5 GHz (5250–5850 MHz) when both diodes were closed. PIN switches on or off can affect antenna's feeding structure, which can solve matching problem caused by change of antenna radiation body structure. In this way, the proposed antenna has good reconfigurable characteristic and high radiation gain.","PeriodicalId":435824,"journal":{"name":"2011 Global Mobile Congress","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133191257","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 : 2011-10-17DOI: 10.1109/GMC.2011.6103935
Xianzhong Xie, Guang Yang, Bin Ma
While primary users (PU) arrive in cognitive radio networks, the current spectrum handoff scheme is that secondary users (SU) have to vacate the spectrum bands which is used and move to other available spectrum bands. This brings frequent spectrum handoffs and degrades the performance of SU even results in service interrupt. Actually SU can still continue to transmit (Underlay) as long as the interference at PU does not exceed a certain threshold. However, the coverage of Underlay is restricted. To overcome aforementioned problem, it is proposed a multi-cell spectrum handoff scheme as a supplement on the coverage of Underlay. Simple additive weights decision algorithm with dynamic weights (SAW-DW) in spectrum handoff is used to select optimal target cell for SU to avoid service interrupt when SU exceeds Underlay constraint. Theoretical analysis and simulation results show that the scheme and algorithm can reduce the probability of handoff failure and service interrupt of SU and improve quality of service.
{"title":"Spectrum handoff decision algorithm with dynamic weights in cognitive radio networks","authors":"Xianzhong Xie, Guang Yang, Bin Ma","doi":"10.1109/GMC.2011.6103935","DOIUrl":"https://doi.org/10.1109/GMC.2011.6103935","url":null,"abstract":"While primary users (PU) arrive in cognitive radio networks, the current spectrum handoff scheme is that secondary users (SU) have to vacate the spectrum bands which is used and move to other available spectrum bands. This brings frequent spectrum handoffs and degrades the performance of SU even results in service interrupt. Actually SU can still continue to transmit (Underlay) as long as the interference at PU does not exceed a certain threshold. However, the coverage of Underlay is restricted. To overcome aforementioned problem, it is proposed a multi-cell spectrum handoff scheme as a supplement on the coverage of Underlay. Simple additive weights decision algorithm with dynamic weights (SAW-DW) in spectrum handoff is used to select optimal target cell for SU to avoid service interrupt when SU exceeds Underlay constraint. Theoretical analysis and simulation results show that the scheme and algorithm can reduce the probability of handoff failure and service interrupt of SU and improve quality of service.","PeriodicalId":435824,"journal":{"name":"2011 Global Mobile Congress","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127413067","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}
IEEE802.11a standard has received considerable attention for adopting multi-carrier modulation called OFDM to improve the performance of data transmission and the effect of resisting multipath expansion. We build an OFDM-based IEEE802.11a platform and do some research on the Symbol synchronization in matlab, which using the cyclic preamble information to synchronize. Two synchronization algorithms are performed, which are maximum correlation and minimum mean-squared error (MMSE) method. Moreover, we conduct some simulations and compare the performance of the two algorithms, and then draw the conclusions.
{"title":"Synchronization algorithm of an OFDM-based IEEE802.11a transmission system","authors":"Kuixi Chen, Jihua Lu, Wanying Xia, Ji'ao Zhang, Shanshi Huang, Yixin Ma","doi":"10.1109/GMC.2011.6103926","DOIUrl":"https://doi.org/10.1109/GMC.2011.6103926","url":null,"abstract":"IEEE802.11a standard has received considerable attention for adopting multi-carrier modulation called OFDM to improve the performance of data transmission and the effect of resisting multipath expansion. We build an OFDM-based IEEE802.11a platform and do some research on the Symbol synchronization in matlab, which using the cyclic preamble information to synchronize. Two synchronization algorithms are performed, which are maximum correlation and minimum mean-squared error (MMSE) method. Moreover, we conduct some simulations and compare the performance of the two algorithms, and then draw the conclusions.","PeriodicalId":435824,"journal":{"name":"2011 Global Mobile Congress","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132182435","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 : 2011-10-17DOI: 10.1109/GMC.2011.6103931
W. Lai, Kai-Ting Yang, Jiaqiang Guo
With rapid progresses in computing technologies, the integrated and ubiquitous computing environment has been developed into Telematics services, which focus on the safety, amusement and information of vehicles. However, high mobility is an essential characteristic in vehicular communication systems, and also the primary cause of challenges. Existing solutions for wireless communication become ineffective or even infeasible in such highly dynamic network topologies. With considering the regular moving patterns of public transportation systems such as buses, trains and shuttles, this paper proposes a novel channel capacity estimation and queue management scheme for VANET. It takes geographic and time considerations into account and develops an efficient channel capacity estimation scheme. Based on the proposed channel capacity estimation scheme, the proposed scheme can well manage the queues at both RSU and vehicle mobile router (VMR). The simulation results are promising and optimistic and can validate the contributions of the proposed scheme.
{"title":"A novel bandwidth prediction and queue management scheme for public transportation systems","authors":"W. Lai, Kai-Ting Yang, Jiaqiang Guo","doi":"10.1109/GMC.2011.6103931","DOIUrl":"https://doi.org/10.1109/GMC.2011.6103931","url":null,"abstract":"With rapid progresses in computing technologies, the integrated and ubiquitous computing environment has been developed into Telematics services, which focus on the safety, amusement and information of vehicles. However, high mobility is an essential characteristic in vehicular communication systems, and also the primary cause of challenges. Existing solutions for wireless communication become ineffective or even infeasible in such highly dynamic network topologies. With considering the regular moving patterns of public transportation systems such as buses, trains and shuttles, this paper proposes a novel channel capacity estimation and queue management scheme for VANET. It takes geographic and time considerations into account and develops an efficient channel capacity estimation scheme. Based on the proposed channel capacity estimation scheme, the proposed scheme can well manage the queues at both RSU and vehicle mobile router (VMR). The simulation results are promising and optimistic and can validate the contributions of the proposed scheme.","PeriodicalId":435824,"journal":{"name":"2011 Global Mobile Congress","volume":"123 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116715690","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 : 2011-10-17DOI: 10.1109/GMC.2011.6103911
Shimin Yang, X. Wen, Wei Zheng, Zhaoming Lu
In this paper, the convergence of Internet of Things (IoT) and 3GPP LTE-A network is discussed. With the cooperation of enormous smart devices, various kinds of information would be gathered and transmitted to the central control and processing entity, 3GPP LTE-A network provides the ideal access network for the IoT. Meanwhile, there exist several potential issues for the convergence of IoT and 3GPP LTE-A network, such as the convergence architecture of the two networks. We propose an enhanced IMS QoS architecture to support the convergence of IoT and 3GPP LTE-A network, and the architecture would provide flexible services with dynamic requirements to both IoT and LTE-A network. In addition, the signaling to support the session establish/release is discussed.
{"title":"Convergence architecture of Internet of Things and 3GPP LTE-A network based on IMS","authors":"Shimin Yang, X. Wen, Wei Zheng, Zhaoming Lu","doi":"10.1109/GMC.2011.6103911","DOIUrl":"https://doi.org/10.1109/GMC.2011.6103911","url":null,"abstract":"In this paper, the convergence of Internet of Things (IoT) and 3GPP LTE-A network is discussed. With the cooperation of enormous smart devices, various kinds of information would be gathered and transmitted to the central control and processing entity, 3GPP LTE-A network provides the ideal access network for the IoT. Meanwhile, there exist several potential issues for the convergence of IoT and 3GPP LTE-A network, such as the convergence architecture of the two networks. We propose an enhanced IMS QoS architecture to support the convergence of IoT and 3GPP LTE-A network, and the architecture would provide flexible services with dynamic requirements to both IoT and LTE-A network. In addition, the signaling to support the session establish/release is discussed.","PeriodicalId":435824,"journal":{"name":"2011 Global Mobile Congress","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125410662","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 : 2011-10-17DOI: 10.1109/GMC.2011.6103908
Yu Li, Ting Zhou, Jing Xu, Zhenhong Li, Haifeng Wang
Cellular controlled Device-to-Device (D2D) system is a local service for future communication systems like LTE, LTE-A, etc. D2D communications can share the Uplink (UL) or Downlink (DL) resources with cellular communications to improve system throughput. Since reusing UL resource or DL resource has different merits in different scenarios, if D2D only reuses either UL or DL resource during the whole communication procedure, there may be some problems, such as load balance, interference, etc. This paper proposes a method for adaptively TDD UL/DL slot utilization for D2D communications according to the change of scenario in TD-LTE system. Analysis is made for illustrating our novel method and the advantages are listed.
{"title":"Adaptive TDD UL/DL slot utilization for cellular controlled D2D communications","authors":"Yu Li, Ting Zhou, Jing Xu, Zhenhong Li, Haifeng Wang","doi":"10.1109/GMC.2011.6103908","DOIUrl":"https://doi.org/10.1109/GMC.2011.6103908","url":null,"abstract":"Cellular controlled Device-to-Device (D2D) system is a local service for future communication systems like LTE, LTE-A, etc. D2D communications can share the Uplink (UL) or Downlink (DL) resources with cellular communications to improve system throughput. Since reusing UL resource or DL resource has different merits in different scenarios, if D2D only reuses either UL or DL resource during the whole communication procedure, there may be some problems, such as load balance, interference, etc. This paper proposes a method for adaptively TDD UL/DL slot utilization for D2D communications according to the change of scenario in TD-LTE system. Analysis is made for illustrating our novel method and the advantages are listed.","PeriodicalId":435824,"journal":{"name":"2011 Global Mobile Congress","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130355392","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 : 2011-10-17DOI: 10.1109/GMC.2011.6103925
Lu Tian, Nicolas Dailly, Qiao Qiao, Jihua Lu, Jiannan Zhang, Jing Guo, Ji'ao Zhang
Voice over IP is a technology that offers voice communication service over IP-based networks. It has been in a focus of much attention in recent years. SIP, the Session Initiation Protocol is an IETF signaling protocol for session management for text and multimedia exchanges, like VoIP, instant messaging, video, on-line games and other services. Various telephony applications and services, such as VoIP, are implemented in Asterisk, a free open source PABX. In this paper, we highlight the configuration of Asterisk to implement normal calls, voice mail, and conferences on a local network with soft phones. Based on the implementations, we discuss about the signaling exchanges for registering, call establishment and termination, DTMF exchanges.
{"title":"Study of SIP protocol through VoIP solution of “Asterisk”","authors":"Lu Tian, Nicolas Dailly, Qiao Qiao, Jihua Lu, Jiannan Zhang, Jing Guo, Ji'ao Zhang","doi":"10.1109/GMC.2011.6103925","DOIUrl":"https://doi.org/10.1109/GMC.2011.6103925","url":null,"abstract":"Voice over IP is a technology that offers voice communication service over IP-based networks. It has been in a focus of much attention in recent years. SIP, the Session Initiation Protocol is an IETF signaling protocol for session management for text and multimedia exchanges, like VoIP, instant messaging, video, on-line games and other services. Various telephony applications and services, such as VoIP, are implemented in Asterisk, a free open source PABX. In this paper, we highlight the configuration of Asterisk to implement normal calls, voice mail, and conferences on a local network with soft phones. Based on the implementations, we discuss about the signaling exchanges for registering, call establishment and termination, DTMF exchanges.","PeriodicalId":435824,"journal":{"name":"2011 Global Mobile Congress","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130492720","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 : 2011-10-17DOI: 10.1109/GMC.2011.6103933
Chun Yang, Wang Jian, Dao-ben Li
A serial concatenated scheme for Overlapped Code Division Multiplexing (OvCDM) system is proposed, characterized in that one or more OvCDM codes are as component codes in serial concatenated OvCDM to make up such a concatenated code with higher spectrum efficiency. The serial concatenated OvCDM uses iterative decoding algorithm based on LOG-MAP Algorithm with soft input soft ouput (SISO). As the simulation results show, the performance of serial concatenated OvCDM is closer to the Shannon limit than that of un-concatenated OvCDM.
{"title":"A serial concatenated scheme for OvCDM","authors":"Chun Yang, Wang Jian, Dao-ben Li","doi":"10.1109/GMC.2011.6103933","DOIUrl":"https://doi.org/10.1109/GMC.2011.6103933","url":null,"abstract":"A serial concatenated scheme for Overlapped Code Division Multiplexing (OvCDM) system is proposed, characterized in that one or more OvCDM codes are as component codes in serial concatenated OvCDM to make up such a concatenated code with higher spectrum efficiency. The serial concatenated OvCDM uses iterative decoding algorithm based on LOG-MAP Algorithm with soft input soft ouput (SISO). As the simulation results show, the performance of serial concatenated OvCDM is closer to the Shannon limit than that of un-concatenated OvCDM.","PeriodicalId":435824,"journal":{"name":"2011 Global Mobile Congress","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121463594","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}