Adversarial attacks and defenses for digital communication signals identification

As modern communication technology advances apace,the digital communication signals identification plays an important role in cognitive radio networks,the communication monitoring and management systems.AI has become a promising solution to this problem due to its powerful modeling capability,which has become a consensus in academia and industry.However,because of the data-dependence and inexplicability of AI models and the openness of electromagnetic space,the physical layer digital communication signals identification model is threatened by adversarial attacks.Adversarial examples pose a common threat to AI models,where well-designed and slight perturbations added to input data can cause wrong results.Therefore,the security of AI models for the digital communication signals identification is the premise of its efficient and credible applications.In this paper,we first launch adversarial attacks on the end-to-end AI model for automatic modulation classifi-cation,and then we explain and present three defense mechanisms based on the adversarial principle.Next we present more detailed adversarial indicators to evaluate attack and defense behavior.Finally,a demonstration verification system is developed to show that the adversarial attack is a real threat to the digital communication signals identification model,which should be paid more attention in future research.

From Spiritual Communication to Digital Communication:Rethinking Marx’s Communication Theory in the Information Age

Karl Marx and Friedrich Engels introduced the theory of spiritual communication in their influential work,The German Ideology,thereby establishing the Marxist perspective on communication.This theory has a distinct historical context,meaning,and significance.As society advances,driven by the proliferation of commodity-based economies and advancements in science and technology,humanity has entered the digital information age.The prevailing mode of communication in this era,centered around the Internet and big data,brings great convenience to society but also raises concerns about the potential alienation of both subjective and objective aspects of communication,as well as social relationships.Against this backdrop,the rethinking of Marx’s communication theory in the 21st century provides a logical framework and theoretical basis for critiquing the contemporary form of spiritual communication through the digital communication of the information age.

The Effect of Latinization on Reading Time and Understanding: Greeklish in Communication and Social Media

The increasing prevalence of technology in society has an impact on young people’s language use and development. Greeklish is the writing of Greek texts using the Latin instead of the Greek alphabet, a practice known as Latinization, also employed for many non-latin alphabet languages. The primary aim of this research is to evaluate the effect of Greeklish on reading time. A sample of 732 young Greeks were asked about their habits when communicating through e-mail and social media with their friends and they then participated in an experiment in which they were asked to read and understand two short texts, one written in Greek and the other in Greeklish. The findings of the research show that nearly one third of the participants use Greeklish. The results of the experiment conducted reveal that understanding is not affected by the alphabet used but reading Greeklish is significantly more time consuming than reading Greek independently of the sex and the familiarity of the participants with Greeklish. The findings suggest that amending social and communication media with software utilities related to Latinization such as language identifiers and converters may reduce reading time and thus facilitate written communication among the users.

Digital Human Rights from the Perspective of System Theory——Concept Definition, Social Function, and Constitutional Basis

The three core issues in the“digital human rights”debate are whether“digital human rights”are possible,necessary,and feasible.Both sides of the debate focus on discovering the value of“digital human rights”to individuals from a semantic level,but ignore the significance of“digital human rights”to the whole society and its subsystems at the level of social structure.By introducing Niklas Luhmann's System Theory,this observation blind spot can be eliminated.Fundamental rights are devoted to directly shaping not a physiological-psychological“individual”as a social environment but a social“person”that can be included by social systems.It is clear that digital human rights are the right to participate in digital communication of a“human”as a“person”,so they are possible in terms of conceptual definition.Digital human rights can help“people”lower the threshold for participation in digital communication,limit the excessive expansion of social systems,and promote the free and complete expression of body and mind,so they are necessary for social functions.There are limitations in the existing two ideas of“incorporating digital human rights into the constitution”.Based on the new construction idea of System Theory of Law,digital human rights as the right to participate in digital communication can be typified into digital communication in social sub-fields such as politics,economy,science,and art.The right to participate constructs a complete digital human rights system,making it feasible on the basis of the constitution.

Digital Communication Using Multi-mode Chaotic Lasers

The digital communication in a system of two multi-mode solid state chaotic lasers is investigated theoretically. If the usual method working well in a single-mode laser system is applied to a multi-mode laser system, the memory effect of the two nearest digits can cause high rate of mistakes when the digits are decoded through the subtraction of receiver output from the transmittal. By introducing the deviations of two nearest maximum and minimum fluctuationsof the signal to decode the digit, the message can be decoded correctly. Also, this communication method does not critically depend on the quality of the chaotic synchronization of the two multi-mode lasers.

New Developments in Maritime Communications： a Comprehensive Survey

This paper summarizes the requirements for modem maritime wireless communication networks in the marine environments including the sea- to-sea and sea-to-shore communication scenarios. The existing maritime wireless communication sys- tems are presented and the development of the state-of-the-art maritime communication systems is surveyed. Furthermore, a hierarchical and integrated maritime network architecture is proposed to satisfy the increasing various classes of services which demand different Quality of Service （QoS）. Finally, the open issues for further development of maritime communications are identified.

Analysis of OFDM Applied to Powerline High Speed Digital Communication

The low voltage powerline is becoming a powerful solution to home network, building automation, and internet access as a result of its wide distribution, easy access and little maintenance. The character of powerline channel is very complicated because it is an open net. This article analysed the character of the powerline channel,introduced the basics of OFDM(Orthogonal Frequency Division Multiplexing), and studied the OFDM applied into powerline high speed digital communication.

Research on the Digital Communication Strategy of Intangible Cultural Heritage under the New Media Environment

In the field of intangible cultural heritage＇ s digital protection, a lot of research work has been made by all countries in the world, while the research on the digital commuuication of intangible cultural heritage is few and especially rarely seen in China. Under the premise, in this paper, the factors influencing intangible cultural heritage in the communication process are analyzed based on the information characteristics of intangible cultural heritage and the advantages of I-Space framework model in researching information transfer. Also, combined with the birch bark making technology in Heilongjiang province, the knowledge-based and signified communication strategy of intangible cultural heritage is proposed, aiming at providing new ideas for the researches on the digital communication of intangible cultural heritage.

Digital communication of two-dimensional messages in a chaotic optical system

The digital communication of two-dimensional messages is investigated when two solid state multi-mode chaotic lasers are employed in a master-slave configuration. By introducing the time derivative of intensity difference between the receiver （carrier） and the transmittal （carrier plus signal）, several signals can be encoded into a single pulse. If one signal contains several binary bits, two-dimensional messages in the form of a matrix can be encoded and transmitted on a single pulse. With these improvements in secure communications using chaotic multi-mode lasers, not only the transmission rate can be increased but also the privacy can be enhanced greatly.

High Speed Electro-Absorption Modulators for Digital and Analog Optical Fiber Communications

An electro-absorption(EA)modulator is one of key components for optical fiber communications due to the high speed,small size,low voltage and integration ability with other semiconductor devices.A 40 Gb/s InGaAsP/InP multiplequantum-well(MQW)EA modulator monolithically integrated with a semiconductor optical amplifier(SOA)was fabricated for digital communications.The modulator capacitance was reduced to obtain 40 GHz bandwidth,and the SOA section helped reduce the insertion loss from 18 dB to 3 dB.InGaAlAs/InP MQW EA modulators have also been fabricated and characterized for analog optical fiber communications.A low driving voltage of 2.7 V and high spurious free dynamic range of 107 dB·Hz2/3 were estimated by static and dynamic measurements.

Digital Communication： The Conflicts in the Transmission and Distribution of Information in the Era of Knowledge Economy

This article analyzes the concentration of production and distribution of information, from the analysis of the news in major international news agencies.The biopolitics is more and more interconnected to social, cultural, economical, and political matters, which led us to see in the contemporary scenario the creation of new forms of social organization which will determine how we interact with each other and how we face the world. Additionally, questions emerge about the usage of the means of communication, particularly those related to Technology of Communication and Information （TICs）. The influence of the media over the social-cultural activities tends to create homogenizations of senses, aiming a planetary visibility in a process that can not only disfigure but destroy many symbolic representations and cultural forms. On the other hand, globalization tends to, instead of minimize the differences in the world, ended up creating new conflicts that, through the usage of new technologies of communication, expresses and articulate themselves.

The Sharing Management of Digital Communication Network Resource

Along with the mature development of the domestic computer technology and communication technology, it is an inevitable trend to integrate the two major information technologies together in the future reform of the social communication model. Under this background, the principle of digital communication is introduced first in this paper, and accordingly the role of the communication network resources sharing is analyzed, and finally the sharing management of digital communication network resources is proposed. Hopefully. this paper can play a help in the future subsequent study.

The Sharing Management of Digital Communication Network Resource

Along with the mature development of the domestic computer technology and communication technology, it is an inevitable trend to integrate the two major information teclmologies together in the future reform of the social communication model. Under this background, the principle of digital co,nmunication is introduced first in this paper, and accordingly the role of the communication network resources sharing is analyzed, and finally the sharing management of digital communication network resources is proposed. Hopefully, this paper can play a help in the future subsequent study.

mm-Wave Communication Systems at W-Band

Two communication systems at W-band are introduced, including the system design, the modulation scheme, etc. TV delivery system delivers picture of quality meeting grade 4.5 over 8 km （no rain）. Digital communication system is capable of operating at data rates up to 8.448 Mb/s beyond 10 km under a BER of 10^-6 （clear）.

High Performance Speech Compression System

Since Pulse Code Modulation emerged in 1937, digitized speech has experienced rapid development due to its outstanding voice quality, reliability, robustness and security in communication. But how to reduce channel width without loss of speech quality remains a crucial problem in speech coding theory. A new full-duplex digital speech communication system based on the Vocoder of AMBE-1000(TM) and microcontroller ATMEL 89C51 is introduced. It shows higher voice quality than current mobile phone system with only a quarter of channel width needed for the latter. The prospective areas in which the system can be applied include satellite communication, IP Phone, virtual meeting and the most important, defence industry.

THE PHASE-OFFSET OVERLAPPED WAVE TECHNIQUE

A new digital communication technology based on the Phase-Offset Overlapped Waves (POOW) has been introduced in this letter. The waves can be considered as a special multicarrier different from traditional ones. The sub-waves in a coded word's period of the POOW are sine waves and have the same frequencies, but different starting phases. The most important characteristic is that these sub-waves are the piecewise functions and not orthogonal in a code word period. The decoding can be implemented by solving a linear equation group. This code has very high efficiency and thus the data transmission rate is increased greatly.

Performance of MIMO Systems Using Space Time Block Codes (STBC)

Digital Communications, in relation to wireless networks, have taken off in recent years due to the expanding need to communicate faster and more efficiently. A popular way to achieve this is by using wireless Multiple Input Multiple Output (MIMO) communication systems. MIMO systems utilize Space Time Block Codes (STBC) as one of the leading ways to obtain higher data rates with limited bandwidth and power. With several STBC methods currently available, this paper analyzes simulations using Orthogonal Space Time Block Codes (OSTBC) in Rayleigh fading channels to evaluate the performance of MIMO systems. The selection to use a Rayleigh fading channel as a model for a non-line-of-sight (nLOS) environment is selected to mimic installations where a large number of signal paths and reflections are expected. All simulations are coded, generated and plotted using MATLAB resulting in graphical data representing the bit-error rate (BER) to signal-to-noise ratio (Eb/N0) or SNR. Each simulation captures how different configurations of key variables including code rate, diversity and antenna count can impact system performance. Four modulation schemes (BPSK, QPSK, 16-QAM and 64-QAM) are included in each simulation. Conclusive evidence based upon these simulations suggests higher diversity gains were achieved with a greater number of antennas. The most significant factor for increasing system performance was using a lower count of transmit antennas with a higher count of receive antennas.

Civic Engagement, Fake News and the Path Forward

Media literacy and understanding the digital information around us are an area of communication that affects all of us. How people are represented in the media, social media and our civic participation affect our representations and understanding of the truth. The author would argue through research and practical examples that civic engagement and associations with a peer group can counteract some of the issues facing digital media today. In an age of the so-called ＂fake news,＂ there are tools we can provide for our teams, our employees, and our collaborators to make sure we are all on the same page and dealing with the same set of verifiable facts

A social media adoption strategy for cultural dissemination in municipalities with tourist potential:Lamas,Peru,as a case study

Social media is commonly used by governments to disseminate information related to transparency and institutional promotion,but its potential for the dissemination of cultural resources is often overlooked.This research proposes a strategy for adopting social media to achieve cultural dissemination in the municipality of Lamas,Peru,which has tourism potential and has been awarded the“Best Tourism Villages”seal of the World Tourism Organisation.Methodologically,we propose a case study at a propositional exploratory level.We start by determining the current state of dissemination of tangible and intangible resources,as well as the practical use of social media,through a survey of 20 officials.The results reveal that crafts are the most widely disseminated tangible resource in the municipality(according to 55%of officials),and intangible resources are occasionally disseminated(50%).We also find that Facebook is the only digital channel used to disseminate cultural information.In this context,we formulate a strategy for adopting social media to improve cultural dissemination,which consists of six phases:(i)forming a work team,(ii)preparing a budget plan,(iii)strengthening capacities,(iv)taking inventory of cultural resources,(v)coordinating community interests and(vi)preparing a cultural dissemination plan.The findings can contribute to formulating public initiatives for the institutionalisation of social media in governments for the purposes of preserving,promoting and guaranteeing the accessibility of cultural heritage.

Simulation analysis on co-site interference of vehicular digital communication system based on IM prediction method by BER

The co-site interference exists in kinds of communication systems, especially in digital communication systems, also is one of the biggest threats ＂in electromagnetic compatibility （EMC） designation of the systems. Analyzing the co-site interference is an important process in achieving EMC performance of the system. Under the situation, the co-site interference simulation analysis of a vehicular digital communication system based on interference margin （IM） prediction method by bit error ratio （BER） was proposed in the paper. In the simulation analysis, some physical models of the vehicular communication system were established on SIMULINK environment, the upper limit of BER level for audio signals was defined as the IM, three different types of co-site interference was analyzed respectively, and the simulation results were obtained in the form of system interference bandwidth. From these results, the EMC performance evaluation of the vehicular communication system was predicted based on the IM prediction method. By comparing with the actual test results, the correctness of the simulation results was validated and the simulation analysis method can be used for reference by other communication systems was indicated.