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Compressive detection of frequency-hopping spread spectrum signals
SPIE Proceedings, 2013In this paper, compressive detection strategies for FHSS signals are introduced. Rapid switching of the carrier frequency among many channels using a pseudorandom sequence makes detection of FHSS signals challenging. The conventional approach to detect these signals is to rapidly scan small segments of the spectrum sequentially.
Feng Liu +3 more
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Tracking of Fast Frequency Hopping Spread Spectrum Signals
MILCOM 1984 - IEEE Military Communications Conference, 1984In this paper tracking of the fast frequency hopping spread spectrum signals is analised. It is shown that the traditional "early-late" (EL) loop cannot be used in the systems in which the hopping rate becomes comparable to the information rate without the system processing gain degradation. Two modifications of this loope are proposed.
Vladan M. Jovanovic, Savo G. Glisic
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An analysis of multipath for frequency hopping spread spectrum ranging
Canadian Conference on Electrical and Computer Engineering, 2005., 2006Frequency hopping spread spectrum (FHSS) ranging is a newly developed radio frequency (RF) technique. With slow frequency hopping, a propagation phase can be obtained for each frequency that is sent. However, each phase is corrupted with multipath, which is a major source of error in RF ranging systems.
null Pei Xu, R.J. Palmer, null Yi Jiang
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Selective reject frequency-hopped spread-spectrum networks
Proceedings of GLOBECOM'96. 1996 IEEE Global Telecommunications Conference, 2002Slow frequency hopped packet radio networks with a selective reject retransmission policy are considered. Each packet consists of different subpackets (codewords), and only those specific subpackets which were received in error are retransmitted. Closed form expressions for subpacket error probabilities are derived for both slotted and unslotted packet
K.A. Mohamed, L. Pap
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Satellite applications of spread spectrum frequency hopping techniques
IEEE Global Telecommunications Conference, 1989, and Exhibition. 'Communications Technology for the 1990s and Beyond, 2003Some features of frequency-hopping (FH) code-division multiple-access (CDMA) techniques are discussed in connection with the mitigation of the effects of interferences in multiple-user satellite systems. The authors show how some specific satellite applications-data relay satellites, space station, mobile satellite systems, VSATs (very small aperture ...
F. Ananasso +4 more
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Interference mitigation in frequency-hopped spread-spectrum systems
2000 IEEE Sixth International Symposium on Spread Spectrum Techniques and Applications. ISSTA 2000. Proceedings (Cat. No.00TH8536), 2002In this paper we explore the error probability of different coding schemes in a frequency-hopped spread-spectrum communication systems subject to partial-band interference and a system subject to Rayleigh fading. The interplay between block length of the code and channel memory is quantified.
A. Worthen, W. Stark
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The analysis of a coherent frequency hopped spread spectrum system
MILCOM 88, 21st Century Military Communications - What's Possible?'. Conference record. Military Communications Conference, 2003A digital joint phase/timing tracking loop for a coherent frequency-hopped spread-spectrum system is analyzed for both training mode and tracking performance. Under minor assumptions, the phase error is modeled as a homogeneous finite Markov chain. The length of the training period, the approximate probability of entering the tracking range, the steady-
null Chun-Meng Su, L.B. Milstein
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Follower jammer considerations for frequency hopped spread spectrum
IEEE Military Communications Conference. Proceedings. MILCOM 98 (Cat. No.98CH36201), 2002Design considerations to be used to account for follower jamming of frequency hopping (FH) spread spectrum systems are presented. A follower jammer attempts to determine the hop frequency with a "determinator" circuit, and then generates jamming in a range about that frequency. Geometrical considerations show the spatial limit at which follower jamming
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A hardware phase continuous frequency synthesiser for frequency hopping spread spectrum
Proceedings. Electrotechnical Conference Integrating Research, Industry and Education in Energy and Communication Engineering', 2003One of the major problems when implementing frequency-hopping spread-spectrum systems is to obtain an accurate, fast, and transient free frequency synthesizer. Direct digital synthesis meets these requirements with economy and simplicity. A brief analysis of a direct digital frequency synthesizer is made, indicating the several sources of noise that ...
F.A.B. Cercas +3 more
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Frequency diversity for a phase-coherent frequency-hopping spread-spectrum system
First IEEE Signal Processing Workshop on Signal Processing Advances in Wireless Communications, 2002The direct-sequence spread-spectrum (DS-SS) signal is conventionally received with a correlator followed by a threshold detector. This receiver, which is optimum in the presence of additive white Gaussian noise (AWGN) is far from optimum in the presence of partial-band (thus, non-white) Gaussian interference.
E. Lance, G.K. Kaleh
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