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Convolutionally coded frequency-hopping communications with nonideal interleaving
IEEE Journal on Selected Areas in Communications, 1990The interleaving span of coded frequency-hopped (FH) systems is often constrained to be smaller than the decoder memory length, i.e. nonideal interleaving is performed. An upper bound on the performance of a Viterbi decoder of a convolutional code with nonideal interleaving is presented.
Shaul Laufer, Arie Reichman
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Sets of Optimal Frequency-Hopping Sequences
IEEE Transactions on Information Theory, 2008 In communication systems, frequency-hopping spread spectrum and direct-sequence spread spectrum are two main spread coding technologies. Frequency-hopping sequences are needed in FH-CDMA systems.
Jianxing Yin
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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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Frequency-Hopping Communication Systems
2003Abstract : This report presents a current review and analysis of the most important aspects of frequency-hopping communication systems. Frequency synthesis and other implementation issues are discussed. The effects and suitability of various modulations is examined. The impact of error-correcting codes on the performance of frequency-hopping systems is
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Capacity of Coherent Frequency-Hop Spread-Spectrum Communications
Proceedings. IEEE International Symposium on Information Theory, 2002The capacity of a coherent frequency-hopped (C-FH) spread-spectrum system is investigated, The channel comprises an M-ary phase-shift keying (M-PSK) modulator, a frequency hopper with phase-continuous carrier, the transmission medium, a nonideal phase-coherent frequency dehopper, an M-PSK demodulator, and a carrier tracking system.
G. Cherubini, W. Stark
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Optical frequency-hop multiple access communications system
ICC '98. 1998 IEEE International Conference on Communications. Conference Record. Affiliated with SUPERCOMM'98 (Cat. No.98CH36220), 2002We propose fast optical frequency-hop code division multiple access (FH-CDMA) for high bandwidth local area networks. Encoding and decoding are achieved by tunable fiber Bragg gratings. Frequency hopping offers many advantages compared to the previously proposed optical CDMA multiple access techniques.
Habib Fathallah +2 more
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Adaptive frequency hopping in HF communications
Proceedings of MILCOM '93 - IEEE Military Communications Conference, 1995Frequency hopping (FH) has been proposed as a technique to combat multipath fading and interference problems in HF links. By means of powerful coding techniques these systems are able to restore the transmitted information also under adverse transmission conditions when several of the frequencies in use are jammed or fading.
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Fundamental limitations on repeater jamming of frequency-hopping communications
IEEE Journal on Selected Areas in Communications, 1989Fundamental limitations on the effectiveness of repeater jamming are derived. These limitations arise because of the geometry and the need for frequency estimation and signal sorting. Limitations on the hopping rate, which might be increased to counter a repeater-jamming threat, are derived from consideration of practical requirements. >
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Design of PLL Frequency Synthesizer in Frequency Hopping Communication System
2010 International Conference on Communications and Mobile Computing, 2010The frequency hopping technology can be used to avoid the frequency-selective attenuation and narrow-band interferences of 10kV power line communication channel. In the frequency-hopping communication system, it always goes through a process of frequency locking.
Yihe Guo, Zhiyuan Xie
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Frequency Compensation in an Adaptive Antenna System for Frequency-Hopping Communications
IEEE Transactions on Aerospace and Electronic Systems, 1987For the full exploitation of an adaptive antenna system forwideband frequency-hopping communications, some form offrequency compensation is necessary. Parameter-dependent,spectral, and anticipative processing are the three methods offrequency compensation that are examined; their strengths,limitations, and variations are discussed.
Don Torrieri, Kesh Bakhru
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