MILCOM 97 MILCOM 97 Proceedings最新文献_第10页

Joint frequency compensation and angle estimation for array processing and FHMA networks 阵列处理与FHMA网络的联合频率补偿与角度估计

MILCOM 97 MILCOM 97 Proceedings Pub Date : 1997-11-02 DOI: 10.1109/MILCOM.1997.648716

Shang-Chieh Liu, E. Geraniotis

{"title":"Joint frequency compensation and angle estimation for array processing and FHMA networks","authors":"Shang-Chieh Liu, E. Geraniotis","doi":"10.1109/MILCOM.1997.648716","DOIUrl":"https://doi.org/10.1109/MILCOM.1997.648716","url":null,"abstract":"A joint frequency compensation and angle estimation array processing technique is proposed to combat the broadband jammers and the performance drop during the hop-to-hop transient time in slow frequency hopping multiple access (FHMA) networks. We use the phase shifting technique, which is based on the direction of arrival (DOA) estimation, to modify the data matrices before the hop happens. A good beamforming weight is thus obtained during the transient period and also helps to find the arriving angle at the end of this hop. The DOA is obtained cheaply in the process of power iterations but as accurately as the costly subspace method. By using these techniques, we can rescue the data at the beginning of each dwell time and allow faster hopping to escape from following jammers. The method also has a good property: as the broadband jammers get closer to the desired signal in azimuth, which results in low received signal to interference and noise ratio (SINR), our proposed frequency compensation method works more efficiently in proportion. When jammers are away, the receiving signals will have high enough SINRs for low bit error rate decoding. Thus, we provide a robust approach in the most difficult communication situations.","PeriodicalId":351392,"journal":{"name":"MILCOM 97 MILCOM 97 Proceedings","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127369598","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}

引用次数: 1

A new bi-conical multibeam antenna for intra-force communications 一种用于部队内部通信的新型双锥多波束天线

MILCOM 97 MILCOM 97 Proceedings Pub Date : 1997-11-02 DOI: 10.1109/MILCOM.1997.648718

D. Cichon, D. Schmidt, E. Gobel

引用次数: 0

Communication performance simulation for the Asia Cellular Satellite System 亚洲蜂窝卫星系统通信性能仿真

MILCOM 97 MILCOM 97 Proceedings Pub Date : 1997-11-02 DOI: 10.1109/MILCOM.1997.648682

M.T. Schiavoni

引用次数: 0

Establishing the requirements for real-time CORBA 建立实时CORBA的需求

MILCOM 97 MILCOM 97 Proceedings Pub Date : 1997-11-02 DOI: 10.1109/MILCOM.1997.646723

A. Inselberg, P. Krupp

引用次数: 1

Analysis and measurements of information transmission over an adaptive delta modulated voice channel 自适应增量调制语音信道上信息传输的分析与测量

MILCOM 97 MILCOM 97 Proceedings Pub Date : 1997-11-02 DOI: 10.1109/MILCOM.1997.646778

P. Lallo

{"title":"Analysis and measurements of information transmission over an adaptive delta modulated voice channel","authors":"P. Lallo","doi":"10.1109/MILCOM.1997.646778","DOIUrl":"https://doi.org/10.1109/MILCOM.1997.646778","url":null,"abstract":"This paper presents voice and data transmission measurements of the present tactical telecommunication network in Finland. EUROCOM recommendations show that adaptive delta modulation (ADM) is suitable only to low frequencies 0...2600 Hz if the sample frequency is 16 kHz. Digital data transmission is the recommended method there. On the other hand a lot of analogue modems are in important use in the tactical networks and they do not have seamless communication through the integrated networks. Problems arise if analogue data has to be transmitted with data modems over the ADM-channel. Still in 1997 a large number of message transmission systems use frequency shift keying (FSK) modems on voice grade circuits over digital voice channels. Also other analogue modems are in use. These message or data transmissions are the basis of the proper operation of weapons and other military systems. Thus it was important to investigate data transmission over tactical networks with analogue modems. Measurements demonstrate the performance of information transmission over the ADM-channel. The quality measure of the ADM-channel itself is the phase and amplitude response characteristics. The quantitative measures are distortion of voice transmission. The quality of the data transmission is measured by the bit error rate (BER). We provide records of these measurements.","PeriodicalId":351392,"journal":{"name":"MILCOM 97 MILCOM 97 Proceedings","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122954916","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}

引用次数: 3

Development and application of the 188-220 protocol test tool (PTT) 188-220协议测试工具(PTT)的开发与应用

MILCOM 97 MILCOM 97 Proceedings Pub Date : 1997-11-02 DOI: 10.1109/MILCOM.1997.645016

J. Zbozny, R. Menell, S. Turczyn, Chinglan Lin

引用次数: 0

Selective slow start: a simple algorithm for improving TCP performance in wireless ATM environment 选择性慢启动:一种提高无线ATM环境下TCP性能的简单算法

MILCOM 97 MILCOM 97 Proceedings Pub Date : 1997-11-02 DOI: 10.1109/MILCOM.1997.648762

U. Varshney

{"title":"Selective slow start: a simple algorithm for improving TCP performance in wireless ATM environment","authors":"U. Varshney","doi":"10.1109/MILCOM.1997.648762","DOIUrl":"https://doi.org/10.1109/MILCOM.1997.648762","url":null,"abstract":"Mobile computing has emerged as an area of significant research and development activities. To support this computing on move, one approach taken by several researchers involves the introduction of the ATM technology in the wireless environment (termed wireless ATM) and the use a suitable transport protocol to support various applications. It is likely that initial implementations will employ TCP (or a modified version of it) as the transport protocol due to the tremendous support it enjoys in the research community. However the problem with existing versions of TCP is a lack of differentiation between segment loss due to the network congestion and due to the handoff in the wireless network. After a segment loss, TCP would initiate a slow start phase to reduce its offered traffic assuming that the network is going through congestion. This may reduce the TCP throughput significantly and will lead to unacceptable performance specially if the underlying wireless ATM network is capable of supporting high data rates. This paper proposes a new algorithm called 'selective slow start', where TCP will attempt to differentiate between segment losses due to the network congestion and due to the handoffs based on the pattern of losses (timeouts). It will initiate the slow start phase in the former case and it will continue to transmit at its current speed in the latter case. Based on the simulation results presented, the SSS algorithm improves the transport layer throughput significantly in a wireless ATM environment.","PeriodicalId":351392,"journal":{"name":"MILCOM 97 MILCOM 97 Proceedings","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129294191","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}

引用次数: 2

Hierarchical, layered modeling and performance evaluation of hybrid communication networks 混合通信网络的分层、分层建模与性能评估

MILCOM 97 MILCOM 97 Proceedings Pub Date : 1997-11-02 DOI: 10.1109/MILCOM.1997.644980

J. Baras, M. S. Corson, K. Jang, M. Li, A. Misra, H. Xie

{"title":"Hierarchical, layered modeling and performance evaluation of hybrid communication networks","authors":"J. Baras, M. S. Corson, K. Jang, M. Li, A. Misra, H. Xie","doi":"10.1109/MILCOM.1997.644980","DOIUrl":"https://doi.org/10.1109/MILCOM.1997.644980","url":null,"abstract":"Commercial and military networks are rapidly becoming hybrid networks; that is interconnected wireless terrestrial, wireline terrestrial and satellite networks. There is a great need for software tools to design, model and also do performance analysis efficiently for such large heterogeneous networks. This is the topic addressed in this paper. The hybrid network modeling and performance evaluation tool is currently under development at the University of Maryland. The tool consists of an algorithmic structure and a software architecture. The algorithm is hierarchical in form, deriving its structure from that of the network which follows the network's routing hierarchy. At each level, a node represents a set of nodes at a lower level. The boundary of a node is characterized by a set of statistical models. The statistics, and their parametric representations for the models of the level 1 nodes are obtained from the OPNET simulations which are run offline. The model defines procedures that convey modeling, simulation and performance data up and down the hierarchy of models. We consider the following performance metrics only: end-to-end delay, throughput, blocking probabilities, cell or packet loss rate. We describe algorithms based on loss network approximations and fast progressive solutions of the resulting fixed point equations.","PeriodicalId":351392,"journal":{"name":"MILCOM 97 MILCOM 97 Proceedings","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128610308","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}

引用次数: 2

CUITN reference and sustainment training [defence data network] CUITN参考及维持训练〔国防数据网络〕

MILCOM 97 MILCOM 97 Proceedings Pub Date : 1997-11-02 DOI: 10.1109/MILCOM.1997.648701

R. Schiffl, J. Vélez

引用次数: 0

A new spread spectrum system using spectral correlation technology 一种利用频谱相关技术的扩频系统

MILCOM 97 MILCOM 97 Proceedings Pub Date : 1997-11-02 DOI: 10.1109/MILCOM.1997.646563

Shiping He, T. Lo, J. Litva

引用次数: 1