Results 241 to 250 of about 2,964,809 (287)

A new family of frequency-hop codes

IEEE Transactions on Communications, 2000
We 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
openaire   +3 more sources

Frequency-Hopped Communications

1991
Spread-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.
openaire   +1 more source

Designing a Differential Frequency Hopping System with Hop Variable Frequency Transition Function

2009 5th International Conference on Wireless Communications, Networking and Mobile Computing, 2009
Differential frequency hopping (DFH) was introduced as a new technology for reliable high data rate transmission in high frequency (HF) bands. Since modulation, coding and frequency hopping are combined together with frequency transition function (FTF) in DFH system.
Binhong Dong, Shaoqian Li, Fengqi Shi
openaire   +1 more source

Frequency Hopped Waveform

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.
openaire   +1 more source

A Spectrally Efficient Frequency Hopping System

IEEE GLOBECOM 2007-2007 IEEE Global Telecommunications Conference, 2007
Frequency 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
openaire   +2 more sources

Frequency-Hopping Systems

2011
Frequency hopping is the periodic changing of the carrier frequency of a transmitted signal. This time-varying characteristic potentially endows a communication system with great strength against interference. Whereas a direct-sequence system relies on spectral spreading, spectral despreading, and filtering to suppress interference. the basic mechanism
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A new construction of frequency-hopping codes

IEEE Communications Letters, 2002
This 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, Guu-Chang Yang, Chia-Ming Yang   +2 more
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A New Algorithm of Frequency Estimation for Frequency-Hopping Signal

2013
The performance of ESPRIT (Estimated Signal Parameters via Rotational Invariance Technique) algorithm about frequency estimation is obviously declined, when the SNR of signal is relatively low. Aiming at this problem, an improved ESPRIT algorithm is presented.
Jun Lv, Weitao Sun, Tong Li 0002
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Frequency hopping

2000
BIRD WILLIAM ERIC, TRIGGS ALAN
openaire   +3 more sources

Constructions of Optimal Uniform Wide-Gap Frequency-Hopping Sequences

IEEE Transactions on Information Theory, 2022
Cuiling Fan, Zhengchun Zhou, Yang Yang   +2 more
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