Results 141 to 150 of about 7,335,937 (187)

Laboratory model communication systems with a frequency hopping

2017 4th International Scientific-Practical Conference Problems of Infocommunications. Science and Technology (PIC S&T), 2017
In this article the main principles of building radiostation with frequency hopping spread spectrum are described. This problem is relevant because of modern powerful facilities for electronic intelligence and jamming. The laboratory model of the modern frequency hopping spread spectrum radiostation with quadrature radio frequency processing was ...
Igor Shostko, Bogdan Butov
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A Frequency-Hopping SSMA System for Speech Communication

IETE Journal of Research, 1983
A frequency-bopping spread-spectrum multiple-access (FH-SSMA) system suitable for speech communication over a TV channel has been described. Design of addresses for the FH-SSMA has been considered. Following an algorithm suggested by Cooper and Nettleton, addresses for 12 subscribers of the system have been obtained. It is shown that a larger number of
G. Madhusudhana Rao, S.L. Maskara
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Synchronization design of frequency-hopping communication system

ICCT'98. 1998 International Conference on Communication Technology. Proceedings (IEEE Cat. No.98EX243), 2002
This paper analyzes some problems in the synchronization design of a frequency hopping communication system. On the base of theoretic research, this paper puts forward a scheme of design of frequency hopping synchronized systems. This scheme has been implemented and good results have been gained.
null Li Weidong, null Wang Jing, null Yao Yan   +2 more
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Frequency-hopping communication with physical-layer chaos encryption

Optics Letters
We propose and numerically demonstrate a scheme that integrates frequency-hopping (FH) communication with physical-layer chaos encryption. In this scheme, chaos synchronization between twin semiconductor lasers driven by a common digital signal is utilized to generate synchronous chaos after optoelectronic conversion and post-processing.
Longsheng, Wang, Siqi, Zhang, Junli, Wang, Yu, Liang, Anbang, Wang, Anni, Liu, Yuncai, Wang   +6 more
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An anticipative adaptive array for frequency-hopping communications

IEEE Transactions on Aerospace and Electronic Systems, 1988
To fully utilize the theoretical processing gain achievable when an adaptive array and frequency hopping are combined, frequency compensation is required. Improved versions of an anticipative adaptive array are examined that provide efficient compensation by adapting the complex weights at each antenna element to the appropriate values for a carrier ...
D. Torrieri, K. Bakhru
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A design framework for frequency hopped communication system

2016 13th International Bhurban Conference on Applied Sciences and Technology (IBCAST), 2016
In this paper, design of a complete turbo-encoded baseband communication system based on frequency hopping technique is presented. The frequency hopping rate is 200 hops/second, modulation is QPSK and overall hopping bandwidth is around 10 MHz. Simulation results are provided to analyze the performance of the designed communication system in terms of ...
Rauf Iqbal, M. Waseem Akhtar, M. Junaid, Fayyaz A. Siddiqui   +3 more
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EMI problems for frequency hopping communication sets

1999 International Symposium on Electromagnetic Compatibility (IEEE Cat. No.99EX147), 2003
To combat electromagnetic interference and to cope with jamming conditions of communication systems, in crowded radio frequency environments, the approach in radio system design is slowly directed towards frequency hopping radio sets. This paper includes features of frequency hopping sets and limitations in MIL-STD-462 towards EMC measurements/testing ...
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Synchronization of Frequency Hopping by LSTM Network for Satellite Communication System

IEEE Communications Letters, 2019
In this letter, a novel method for synchronization of frequency hopping signal is proposed for tactical satellite communication system. Proposed method consists of serial search for coarse acquisition and use of long short-term memory (LSTM) network for fine acquisition. During training, the LSTM network is able to learn trend of energy signal used for
Sangkeum Lee 0001, Suil Kim, Minah Seo, Dongsoo Har   +3 more
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Adaptation of the Code Rate and Transmitter Power in Frequency-Hop Communications

IEEE Transactions on Wireless Communications, 2004
An adaptive transmission technique for frequency-hop packet transmission is described and its performance is evaluated for certain channels with unknown or time-varying parameters. The power in the transmitted signal and the rate of the error-control code are adapted in a way that provides energy-efficient communications.
Michael B. Pursley, Clint S. Wilkins
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An Anticipative Adaptive Array for Frequency-Hopping Communications

MILCOM 1987 - IEEE Military Communications Conference - Crisis Communications: The Promise and Reality, 1987
Adaptive antenna array processing and wideband frequency hopping are two of the most powerful methods for providing interference rejection in military communication systems. However, for the full exploitation of the theoretical processing gain achievable when these two methods are combined, frequency compensation is required.
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