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Article
Publication date: 25 August 2021

Nitin Tejram Deotale

To enhance the performance transmit antenna selection (TAS) of spatial modulation (SM), systems technique needs to be essential. This TAS is an effective technique for reducing…

39

Abstract

Purpose

To enhance the performance transmit antenna selection (TAS) of spatial modulation (SM), systems technique needs to be essential. This TAS is an effective technique for reducing the multiple input multiple output (MIMO) systems computational difficulty, and bit error rate (BER) can increase remarkably by various TAS algorithms. But these selection methods cannot provide code gain, so it is essential to join the TAS with external code to obtain cy -ode gain advantages in BER.

Design/methodology/approach

In this paper, Bose–Chaudhuri–Hocquenghem (BCH)-Turbo code TC is combined with the orthogonal space time block code system.

Findings

In some existing work, the improved BER has been perceived by joining forward error correction code and space time block code (STBC) for MIMO systems provided greater code gain. The proposed work can provide increasing code gain and the effective advantages of the TAS-OSTBC system.

Originality/value

To perform the system analysis, Rayleigh channel is used. In the case with multiple TAS-OSTBC systems, better performance can provide by this new joint of the BCH-Turbo compared to the conventional Turbo code for the Rayleigh fading.

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Article
Publication date: 28 June 2023

Ahmet Esat Süzer and Hakan Oktal

The main aim of this study is to elaborately examine the error correction technology for global navigation satellite system (GNSS) navigation messages and to draw a conceptual…

168

Abstract

Purpose

The main aim of this study is to elaborately examine the error correction technology for global navigation satellite system (GNSS) navigation messages and to draw a conceptual decision support framework related to the modernization of the GNSS and other systems.

Design/methodology/approach

The extensive simulation model developed in Matrix Laboratory (MATLAB) is used to evaluate the performance of forward error correction (FEC) codes such as Hamming, Bose–Chaudhuri–Hocquenghem, convolutional, turbo, low-density parity check (LDPC) and polar codes under different levels of noise.

Findings

The performance and robustness of the aforementioned algorithms are compared based on the bit length, complexity and execution time of the GNSS navigation message. In terms of bit error rate, LDPC coding exhibits more ability in the robustness of the navigation message, while polar code gives better results according to the execution time.

Practical implications

In view of future new GNSS signals and message design, the findings of this paper may provide significant insight into navigation message modernization and design as an important part of GNSS modernization.

Originality/value

To the best of the authors’ knowledge, this is the first study that conducts a direct comparison of various FEC algorithms on GNSS navigation message performance against noise, taking into consideration turbo and newly developed polar codes.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 8
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 4 September 2009

Fulvio Babich, Massimiliano Comisso and Lucio Manià

The purpose of this paper is to compare the low‐cost switched‐beam antennas and the more expensive adaptive antennas in a wireless mesh network (WMN) scenario.

390

Abstract

Purpose

The purpose of this paper is to compare the low‐cost switched‐beam antennas and the more expensive adaptive antennas in a wireless mesh network (WMN) scenario.

Design/methodology/approach

A mathematical framework is adopted in order to determine, for the two antenna systems, the number of sustainable simultaneous communications and the achievable throughput of a backbone WMN in a realistic outdoor environment.

Findings

The paper includes a thorough examination of benefits and crucial implementation issues concerning the adoption multiple antennas on mesh routers.

Originality/value

The paper investigates the relationship between the antenna system and the adopted channel coding technique, to determine the set‐up that may offer the best compromise between performance and complexity.

Details

International Journal of Pervasive Computing and Communications, vol. 5 no. 3
Type: Research Article
ISSN: 1742-7371

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Article
Publication date: 1 March 1998

Lars Skyttner

To enhance the generality and usefulness of classic communication theory, some complementary concepts and ideas have been introduced and commented against the background of…

3720

Abstract

To enhance the generality and usefulness of classic communication theory, some complementary concepts and ideas have been introduced and commented against the background of General Living Systems Theory (GLS). The paper begins with an extended definition of the problem of communication and continues with a presentation of the concept of natural channels. Basic ideas like the interrelation between time, place, and channel with its four different categories of communication are presented. Also main qualities of a message like informability, detectability, and localizability are analysed. Finally some general ideas regarding coding and transmission of messages are presented. The paper ends with the conclusion that classic communication theory still is highly relevant with no serious anomalies threatening its existence. This truth is confirmed by the fact that the complementary concepts presented here fit well into its existing framework.

Details

Kybernetes, vol. 27 no. 2
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 7 September 2020

Bilal Alhayani and Abdallah Ali Abdallah

The manufacturing of intelligent and secure visual data transmission over the wireless sensor network is key requirement nowadays to many applications. The two-way transmission of…

259

Abstract

Purpose

The manufacturing of intelligent and secure visual data transmission over the wireless sensor network is key requirement nowadays to many applications. The two-way transmission of image under a wireless channel needed image must compatible along channel characteristics such as band width, energy-efficient, time consumption and security because the image adopts big space under the device of storage and need a long time that easily undergoes cipher attacks. Moreover, Quizzical the problem for the additional time under compression results that, the secondary process of the compression followed through the acquisition consumes more time.

Design/methodology/approach

Hence, for resolving these issues, compressive sensing (CS) has emerged, which compressed the image at the time of sensing emerges as a speedy manner that reduces the time consumption and saves bandwidth utilization but fails under secured transmission. Several kinds of research paved path to resolve the security problems under CS through providing security such as the secondary process.

Findings

Thus, concerning the above issues, this paper proposed the Corvus corone module two-way image transmission that provides energy efficiency along CS model, secured transmission through a matrix of security under CS such as inbuilt method, which was named as compressed secured matrix and faultless reconstruction along that of eminent random matrix counting under CS.

Originality/value

Experimental outputs shows intelligent module gives energy efficient, secured transmission along lower computational timing also decreased bit error rate.

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Article
Publication date: 7 September 2015

Peter Cariani

The purpose of this paper is to outline an integrative, high-level, neurocomputational theory of brain function based on temporal codes, neural timing nets, and active…

261

Abstract

Purpose

The purpose of this paper is to outline an integrative, high-level, neurocomputational theory of brain function based on temporal codes, neural timing nets, and active regeneration of temporal patterns of spikes within recurrent neural circuits that provides a time-domain alternative to connectionist approaches.

Design/methodology/approach

This conceptual-theoretical paper draws from cybernetics, theoretical biology, neurophysiology, integrative and computational neuroscience, psychology, and consciousness studies.

Findings

The high-level functional organization of the brain involves adaptive cybernetic, goal-seeking, switching, and steering mechanisms embedded in percept-action-environment loops. The cerebral cortex is conceived as a network of reciprocally connected, re-entrant loops within which circulate neuronal signals that build up, decay, and/or actively regenerate. The basic signals themselves are temporal patterns of spikes (temporal codes), held in the spike correlation mass-statistics of both local and global neuronal ensembles. Complex temporal codes afford multidimensional vectorial representations, multiplexing of multiple signals in spike trains, broadcast strategies of neural coordination, and mutually reinforcing, autopoiesis-like dynamics. Our working hypothesis is that complex temporal codes form multidimensional vectorial representations that interact with each other such that a few basic processes and operations may account for the vast majority of both low- and high-level neural informational functions. These operational primitives include mutual amplification/inhibition of temporal pattern vectors, extraction of common signal dimensions, formation of neural assemblies that generate new temporal pattern primitive “tags” from meaningful, recurring combinations of features (perceptual symbols), active regeneration of temporal patterns, content-addressable temporal pattern memory, and long-term storage and retrieval of temporal patterns via a common synaptic and/or molecular mechanism. The result is a relatively simplified, signal-centric view of the brain that utilizes universal coding schemes and pattern-resonance processing operations. In neurophenomenal terms, waking consciousness requires regeneration and build up of temporal pattern signals in global loops, whose form determines the contents of conscious experience at any moment.

Practical implications

Understanding how brains work as informational engines has manifold long-reaching practical implications for design of autonomous, adaptive robotic systems. By proposing how new concepts might arise in brains, the theory bears potential implications for constructivist theories of mind, i.e. how observer-actors interacting with one another can self-organize and complexify.

Originality/value

The theory is highly original and heterodox in its neural coding and neurocomputational assumptions. By providing a possible alternative to standard connectionist theory of brain function, it expands the scope of thinking about how brains might work as informational systems.

Details

Kybernetes, vol. 44 no. 8/9
Type: Research Article
ISSN: 0368-492X

Keywords

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Article
Publication date: 1 April 1998

Lars Skyttner

The ideas of information theory which underlie cybernetics and its information‐processing aspects still has a solid reputation to be both extremely abstract and highly…

1922

Abstract

The ideas of information theory which underlie cybernetics and its information‐processing aspects still has a solid reputation to be both extremely abstract and highly mathematical. Furthermore, the tract has been accused of a slow development and not accentuating the difference between information and communication theories. In this paper an attempt is made to demonstrate that principles and concepts used in information theory can be both understood and used from a psychological basis ‐ without the use of complicated mathematics. The difference between information and communication theory is considered as well as some new and revolutionary concepts. The study shows that the influences of the investigated area have grown considerably with the contributions from information physics.

Details

Kybernetes, vol. 27 no. 3
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 30 April 2020

Kishor Purushottam Jadhav, Amita Mahor, Anirban Bhowmick and Anveshkumar N.

Non-orthogonal multiple access (NOMA) is a much hopeful scheme, which is deployed to enhance the spectral efficiency (SE) significantly, and it also enhances the massive access…

181

Abstract

Purpose

Non-orthogonal multiple access (NOMA) is a much hopeful scheme, which is deployed to enhance the spectral efficiency (SE) significantly, and it also enhances the massive access that has attained substantial concern from industrial and academic domains. However, the deployment of superposition coding (SC) at the receiver side resulted in interference. For reducing this interference, “multi-antenna NOMA” seems to be an emerging solution. Particularly, by using the channel state information at the transmitter, spatial beam forming could be deployed that eliminates the interference in an effective manner.

Design/methodology/approach

This survey analyzes the literature review and diverse techniques regarding the NOMA-based spatial modulation (SM) environment. It reviews a bunch of research papers and states a significant analysis. Initially, the analysis depicts various transmit antenna selection techniques that are contributed in different papers. This survey offers a comprehensive study regarding the chronological review and performance achievements in each contribution. The analytical review also concerns on the amplitude phase modulation (APM) selection schemes adopted in several contributions. Moreover, the objective functions adopted in the reviewed works are also analyzed. Finally, the survey extends with various research issues and its gaps that can be useful for the researchers to promote improved future works on NOMA-based SM.

Findings

This paper contributes to a review related to NOMA-based SM systems. Various techniques and performance measures adopted in each paper are analyzed and described in this survey. More particularly, the selection of transmission antenna and APM are also examined in this review work. Moreover, the defined objective function of each paper is also observed and made a chronological review as well. Finally, the research challenges along with the gaps on NOMA-based SM systems are also elaborated.

Originality/value

This paper presents a brief analysis of NOMA-based SM systems. To the best of the authors’ knowledge, this is the first work that uses NOMA-based SM systems to enhance SE.

Details

International Journal of Pervasive Computing and Communications, vol. 16 no. 2
Type: Research Article
ISSN: 1742-7371

Keywords

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Article
Publication date: 1 February 1974

CALVIN N. MOOERS

The papers by Robert A. Fairthorne are always both stimulating and challenging to me. Their insights and their obscurities are fascinating. While my own intellectual works have…

33

Abstract

The papers by Robert A. Fairthorne are always both stimulating and challenging to me. Their insights and their obscurities are fascinating. While my own intellectual works have usually been quite separate from his, we have frequently shared a concern with many of the same topics in the principles of information work. These have included such topics as the mathematical basis of classification, applications of mathematical lattice theory, insights from Shannon's signalling theory (habitually misnamed ‘information theory’), and the delegation of retrieval.

Details

Journal of Documentation, vol. 30 no. 2
Type: Research Article
ISSN: 0022-0418

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Article
Publication date: 1 July 1961

THE MIDAS comprehensive routine flight data recording system has been developed from equipment used primarily for aircraft research and testing programmes. Almost every operating…

41

Abstract

THE MIDAS comprehensive routine flight data recording system has been developed from equipment used primarily for aircraft research and testing programmes. Almost every operating parameter in an aircraft in the course of normal operations is transduced into electrical form for the purpose of aircraft instrumentation, and due to the high input impedance of the MIDAS CMM 400 series recorders a parallel connexion to the transducer circuit is generally all that is necessary in the way of installation wiring. Suitable compact and easily installed commercial types of transducers are readily available to meet any special requirements. As these parameters already exist in electrical form it is a comparatively simple step to transfer them to magnetic tape. A frequency modulated type of coding system is used.

Details

Aircraft Engineering and Aerospace Technology, vol. 33 no. 7
Type: Research Article
ISSN: 0002-2667

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