Results 231 to 240 of about 2,964,810 (286)
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A performance comparison of differential frequency hopping and fast frequency hopping
IEEE MILCOM 2004. Military Communications Conference, 2004., 2005This paper discusses the multiple access performance of the spread spectrum modulation called differential frequency hopping (DFH) and its associated signal processing algorithms, and compares DFH performance to the performance of fast frequency hopping (FFH) multiple access systems.
D.G. Mills, D.E. Egnor, G.S. Edelson
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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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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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A new family of frequency-hop codes
IEEE Transactions on Communications, 2000We give an algebraic construction for a new family of frequency-hop codes. The construction is based on properties of finite fields: it is shown that for each field GF(p/sup m/), there exists a large number of codes of length p/sup m/. The codes are also shown to possess the best possible simultaneous two-dimensional autocorrelation and cross ...
Oscar Moreno, Svetislav V. Maric
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A Spectrally Efficient Frequency Hopping System
IEEE GLOBECOM 2007-2007 IEEE Global Telecommunications Conference, 2007Frequency hopping systems have been widely used in military communications to prevent hostile jamming, interception and detection. In traditional frequency hopping (FH) systems, the transmitter hops in a pseudo-random manner among available frequencies according to a pre-specified algorithm, and the receiver operates accordingly in exact ...
Tongtong Li, Qi Ling, Jian Ren 0001
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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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A new construction of frequency-hopping codes
IEEE Communications Letters, 2002This article presents a new construction of frequency-hopping (FH) codes for multilevel frequency-shift-keying/frequency-hopping code-division multiple-access (MFSK/ FH-CDMA) systems. Exactly P/sup 3/-P FH patterns of length P/sup 3/ and frequency slots P/sup 3/ are constructed for every prime, P. These new FH patterns possess ideal autocorrelation and
Junjie Chen +2 more
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Code Acquisition for a Frequency-Hopping System
IEEE Transactions on Communications, 1987Code acquisition for a frequency-hopping code-division multiple-access system using Reed-Solomon coding is investigated. The one-coincidence codes which minimize the user interference are shown to be well suited for initial synchronization but are less appropriate for regaining synchronism during transmission.
István Vajda, Gudmundur Einarsson
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Frequency-Hopped Communications
1991Spread-spectrum communications may also be achieved by using frequency hopping of the RF carrier. Instead of direct-phase shift modulation of a digital sequence onto the RF carrier, as in DS-CDMA, the sequence is used to frequency hop the carrier. In this chapter we examine the basic elements of this type of communication link.
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2013
In this book we have reviewed two LPI radar signal waveforms, FMCW and phase-coded. The complexity of FMCW technology is minimal and it is very popular because of this reason. There are only two major obstacles that can be construed as a disadvantage in FMCW radars.
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In this book we have reviewed two LPI radar signal waveforms, FMCW and phase-coded. The complexity of FMCW technology is minimal and it is very popular because of this reason. There are only two major obstacles that can be construed as a disadvantage in FMCW radars.
openaire +1 more source