Results 231 to 240 of about 2,964,809 (287)
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Characterization of the frequency stability of frequency-hopping sources
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 1991A method that applies time-domain stability measures, hitherto used only in the context of fixed-frequency sources, to the characterization of frequency-hopped sources is introduced. This method has been successfully applied to the testing of a novel practical frequency-hopping synthesizer. It is shown that despite the fact that hopping sources exhibit
G A, Kalivas, R G, Harrison
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Design of frequency synthesizer in frequency-hopping transceiver
2013 IEEE 10th International Conference on ASIC, 2013Several key techniques of PLL-type (Phase-Locked Loop) frequency synthesizer for frequency-hopping transceiver are studied. Its structure is analyzed and the main parameters are proposed. A monolithic LC-tuned voltage controlled oscillator (LC-VCO) with low phase noise is fabricated in a TSMC 0.18μm RF (radio frequency) CMOS technology.
Yong Xu +5 more
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Assignment of Frequency Lists in Frequency Hopping Networks
IEEE Transactions on Vehicular Technology, 2005Metaheuristic algorithms for frequency assignment problems have received considerable attention in the literature, but few papers have addressed the question of list assignment in frequency hopping networks. The work of Bjo/spl uml/rklund, Va/spl uml/rbrand, and Yuan is a notable exception, which will be extended here in a number of directions.
Jim N. J. Moon +2 more
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On the asynchronous frequency hopping systems performance
12th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications. PIMRC 2001. Proceedings (Cat. No.01TH8598), 2002An analytical performance characterization of frequency hopping systems, in asynchronous environment, has been derived by means of a closed formula. The system considers a forward error correction code to counteract the partial overlap interesting two successive slots if a frequency collision occurs.
Giovanardi A., Mazzini G.
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Clustering and frequency allocation in frequency hopping tactical networks
MILCOM 2015 - 2015 IEEE Military Communications Conference, 2015Next generation tactical networks has to provide high data rate and low delay, along with multiple applications with strict QoS requirements. In this work we address the problems of clustering and frequency allocation in TDMA-based frequency-hopping tactical networks.
Kılıç, Gökhan +5 more
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Time hopping and frequency hopping in ultrawideband systems
2003 IEEE Pacific Rim Conference on Communications Computers and Signal Processing (PACRIM 2003) (Cat. No.03CH37490), 2004This paper analyzes frequency-hopping (FH) and time-hopping (TH) as multiple access format for ultrawideband communications. We apply the concept of "fourthegy", recently introduced by Subramanian and Hajek, to both TH and FH. We find that the design rules are different for FCC-compliant systems (where the power spectral density is limited) than for ...
A.F. Molisch, J. Zhang, M. Miyake
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Time-hopping and frequency-hopping multiple-access packet communications
IEEE Transactions on Communications, 1990Time-hopping and frequency-hopping multiple-access (TH/FHMA) packet communication systems are proposed and investigated. In TH/FHMA communication systems, a message packet is encoded into several subpackets via a Reed-Solomon error correcting code. The subpackets are transmitted over the channel using time-hopping and frequency-hopping patterns.
Alex W. Lam, Dilip V. Sarwate
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1994
One major problem with moment-matching schemes described so far is that they offer no means of pre-determining the accuracy range of the approximation. Pade approximations are accurate in the neighbourhood of an approximation. If that neighbourhood contains most of the signal energy (most of the large residues and poles close to the origin) then the ...
Eli Chiprout, Michel S. Nakhla
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One major problem with moment-matching schemes described so far is that they offer no means of pre-determining the accuracy range of the approximation. Pade approximations are accurate in the neighbourhood of an approximation. If that neighbourhood contains most of the signal energy (most of the large residues and poles close to the origin) then the ...
Eli Chiprout, Michel S. Nakhla
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Low-complexity hop timing synchronization in frequency hopping systems
2006 IEEE International Symposium on Circuits and Systems, 2006This paper considers the problem of synchronization in frequency hopping systems. A simple digital signal processing block along with the existing RF circuits forms a phase detector that generates a signal corresponding to the phase difference between the hop timings of the local and received signals.
Mi-Kyung Oh, Byunghoo Jung, Dong-Jo Park
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On the Sidel'nikov Sequences as Frequency-Hopping Sequences
IEEE Transactions on Information Theory, 2009A (v,l, lambda)-FHS denotes a frequency-hopping sequence of length v over a frequency set of size l with maximum out-of-phase Hamming autocorrelation lambda. Recently, Ding and Yin constructed two FHS families for a prime power q satisfying q=ef+1 with positive integers e and f . Theorems 4 and 5 in their paper claim that these two FHS families include
Han, YK, Yang, K
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