Earticle

기상, 해양 및, Ka-대역 통신 탑재체를 탑재하고 정지궤도에서 기상 및 해양 감시 임무 및 통신 서비스를 수행하는 통신해양기상위성은 기상 및 해양 탑재체에서 관측된 원시 데이터의 지상국 전송 및 지상국에서 처리된 기상 데이터의 최종 사용자국에게 중계 전송을 기상해양데이터통신 서브시스템이 있다. 기상해양데이터통신 서브시스템은 기상 및 해양 탑재체에서 수집된 원시 데이터를 받아 CCSDS 권고안에 준하여 포맷하고 증폭기를 거쳐 지상국에 전송하는 SD 채널과 지상국에서 처리된 기상 데이터를 CGMS 권고안에 따라 LRIT/HRIT 포맷팅된 신호를 최종 사용자국에 중계하는 기능을 제공하는 MPDR 채널로 구성된다. 본 논문은 관측 데이터 전송 및 중계를 위해 구성된 기상 해양데이터통신 서브시스템을 구성하고 서브시스템 예비 성능 해석을 통해 주요 요구 성능 파라미터의 만족 여부를 확인하는데 있다.

The COMS (Communication, Ocean, and Meteorological Satellite) performing meteorological and ocean monitoring and providing communication service with meteorological, ocean and Ka-band payload in the geostationary orbit includes MODCS (Meteorological and Ocean Data Communication Subsystem) which provides transmitting the raw data collected by meteorological payload called MI (Meteorological Imager) and ocean payload named GOCI (Geostationary Ocean Color Imager) to the ground station and relaying the meteorological data processed on the ground to the end-user stations. MODCS comprises of two channels: SD channel which formats the raw data according to CCSDS recommendation, amplifies and transmits its signal to the ground station; MPDR channel which relays to the end-user stations the ground-processed meteorological data in the data format of LRIT/HRIT recommended by CGMS. This paper constructs the architecture of MODCS for transmitting and relating the observed data, and investigates that the key performance parameters have the required margin through the preliminary performance analyses.

The communication performance can be restricted by inevitable training overhead for acquiring channel state information (CSI). A space?time code (STC)-based cooperative communication scheme is proposed to reduce the training overhead by employing a two-antenna relay node (RN) that broadcasts merely two orthogonal pilot sequences from the two antennas to a source node (SN) and a destination node (DN). The received signal-to-noise ratio, the achievable rate, and the bit error rate are mathematically analyzed, and numerical results confirm that the proposed STC-based relay system increases the achievable rate irrespective of the number of antennas at SN and DN.

This letter proposes a powerful method to reconstruct the spectral image frames for increasing data transmission capability in Display Field Communication (DFC) systems. The proposed method reconstructs the spectral image iteratively using the good data symbol estimates fed back by the camera decoder. To begin with, initial image is estimated by means of known pilot symbols. Then, hard symbol decisions obtained by iterative decoding are used to improve the quality of the reconstructed image. The proposed technique selects good data pixels using hard information from the decoder and performs re-estimation of the image pixels. From numerical simulations, we show that the proposed method significantly boosts the data transmission capacity of the DFC system over the conventional DFC that uses reference frames.

By leveraging the characteristics of both quantum encoding and classical data channel, we present a unique and novel multiuser optical communication system that utilizes fascinating properties of the structured light for information transmission. Specifically, we propose an indoor orbital angular momentum (OAM) multiuser multiple-input multiple-output (MIMO) optical communication system, where the quantum encoding is performed and the multiuser transmission is then analyzed from the context of the classical data channel. In the proposed system, as the OAM beam propagates, its angular spread is analyzed. In addition, we show that the variance of the beam divergence increases with the increasing OAM index mode on the basis of the derived MIMO channel impulse response for OAM carrying Laguerre?Gaussian beams. Comparative studies reveal that the proposed system significantly outperforms the conventional non-orthogonal multiple access (NOMA) applied with MIMO.

In this paper, For 4th generation wireless communication systems, we propose a method to predict FH patterns in FHOFDMA systems. OFDM is recognized as a promising modulation technique. Multi-user allocation in OFDM system can use FH that provides the spectrum-spread techniques. If one can generate more predictable FH sequences, then performance of the system can be easily improved. Current random FH and simple adaptive FH methods, however, are not considering predicting FH sequences. In this paper we show that the sampling of the wireless faded signal is not realized as a certain probability nature. With this regard, the proposed predictive FH allocation method is designed to embed the unknown probability models. Simulation study shows that the predictive FH method is more accurately predict FH sequences than the random or simple adaptive FH methods. We will further improve this proposed method to apply QoS control and MAC function development in OFDMA based wireless physical structures, especially maritime wireless data communications.

스마트팩토리는 제조생산 전 과정이 디지털 자동화 솔루션으로 결합돼 생산성 및 품질, 그리고 고객만족도를 향상시키는 지능형 공장으로 스스로 제어할 수 있는 공장을 말한다. 독일, 유럽, 미국 등을 중심으로 전세계 제조 산업에서 급속도로 변화하고 있다. 우리 정부도 이러한 변화에 대응하기 위해 중소중견기업을 위한 스마트팩토리 보급확산 정책을 펼치고 있으며 산업자원통상부, 중소벤처기업부, 중소기업기술정보진흥원, 각 지역 테크노파크 등 관계부처 및 기관들과 삼성, SK, LG 등 대기업들이 스마트팩토리 지원 사업에 적극적인 투자를 하며 제조 스마트화에 나서고 있다[1]. 공장자동화(Factory Automation, FA) 구축에는 이기종 장비의 연결에 대해 많은 이슈들이 있다. 다양한 장비로부터의 다양한 통신 구성이 가장 힘든 측면이 그 이유이다. 같은 회사 제품들로만 구성되거나 표준안이 존재하면 모르겠지만, 오래된 장비와 최신의 장비, 사용 환경도 제각각인 장비들이 일련의 통신을 통해 통합 구축을 하려니 구축하기가 쉽지 않다. 이런 문제점을 해결하기위한 방법으로 전 세계적으로 널리 보급되어 있는 자동화 프로토콜의 하나이고, 대표적인 설비 제어시스템인 PLC의 수많은 공업 기기에서 통신표준으로 사용하고 있는 FieldBus중 하나인 Modbus를 이용하여 통신 하는 방안을 제시하고자 한다.

Smart Factory refers to a factory that can be controlled by itself with an intelligent factory that improves productivity, quality and customer satisfaction by combining the entire process of manufacturing and production with digital automation solutions. The manufacturing industry around the world is rapidly changing, with Germany, Europe, and the United States at the center. In order to cope with such changes, the Korean government is also implementing a policy to spread the supply of smart factories for small and medium-sized companies, and related ministries and agencies such as the Ministry of Commerce, Industry and Energy, the Ministry of SMEs and Venture Business, the Korea Institute of Technology and Information Promotion, and local technoparks, as well as large companies such as Samsung, SK and LG are actively investing in smart manufacturing projects to support smart factories[1]. Factory Automation (FA) construction has many issues regarding the connection of heterogeneous equipment. The most difficult aspect of configuring various communications from various equipment is the reason. Although it may not be known if there are standards or products made up of the same company, it is not easy to build equipment that is old, up-to-date, and different use environments through a series of communications. To solve this problem, we would like to propose a method of communication using Modbus, one of FieldBus, which is one of the many industrial devices of PLC, a representative facility control system, and is used as a communication standard.

본 논문에서는 낮은 위성채널 대역폭을 이용한 서비스 적응적인 전술 데이터 전송 프로토콜(STTS, Service-adaptive Tactical-data Transport Stream)을 제안한다. STTS는 기존 디지털 방송 표준인 DVB-S 및 DVB-S2의 전송 스트림 표준을 기반으로 서비스 확장성을 위한 추가 필드 및 신뢰성 보장을 위한 스케줄러를 제공하도록 설계된다. 또한, 다양한 전술 데이터를 낮은 대역폭으로 전송하기 위해서 트래픽 모델과 중요 데이터의 재전송 기능이 데이터 전송 패킷 손실에 미치는 영향을 시뮬레이션을 통하여 검증하 고, 이를 기반으로 STTS를 적용한 시스템 설계 시 고려할 사항을 확인한다.

In this paper, we propose a Service-adaptive Tactical Data Transmission Protocol (STTS) based on Satellite Communications with narrow bandwidth. STTS is designed to provide additional field for scalability and scheduler for reliability of transport stream protocol based on digital broadcasting standard, DVB-S and DVB-S2. It is also verified the effects of lost data packets with narrow bandwidth through the simulator by traffic model and re-transmission of critical data, and checked the design considerations based on STTS system.

본 연구는 국가 행정기관으로서 다양한 홍보 사업을 진행하는 방송통신위원회(방통위)의 유튜브 홍보 콘텐츠와 콘텐츠 이용자 반응을 비교하여 효율적인 홍보 사업 진행 을 위한 전략적 제언을 제시함을 목표로 한다. 이를 위해 방통위의 홍보 영상 제목과 소개글을 분석하여 유튜브에서 형성되는 홍보 담론을 파악하고, 이를 이용자들의 댓글 에서 나타나는 담론과 비교하였다. 2018년 1월부터 2022년 12월까지 ‘방송통신위원회’ 유튜브 채널에 게시된 504개의 영상과 이에 달린 8,114개의 댓글 데이터를 수집 하였으 며, 이들 데이터에서 추출된 상위 50개의 키워드를 바탕으로 구조적 등위성 분석을 실 시하였다. 또한, 기초 통계 분석과 키워드 빈도 및 중요도 분석을 통해 지난 5년간의 홍 보 성과를 평가하고, 이를 바탕으로 더욱 효과적인 유튜브 정책 홍보 전략을 제안하였 다. 분석 결과는 다음과 같다: 1) 빈도수 측면에서 방통위는 기관명과 기관 서비스를 중 심으로 많이 언급하여 홍보하려 했지만, 콘텐츠 이용자들은 기관에 대한 관심보다는 개 별 홍보 사업 주제와 해당 홍보 콘텐츠/캐릭터에 대해 더 큰 관심을 보였다. 2) 빈도수 측면에서 방통위 기관명은 상대적으로 이용자 댓글에서 많이 언급되지 않았지만 댓글에 대한 구조적 등위성 분석 결과 방통위 기관명은 긍정적인 감정 언어와 같은 군집을 형성하고 있었으며, 이를 통해 방통위의 유튜브 홍보 활동이 기관에 대한 이용자들의 인식에 긍정적인 기여를 하고 있음을 확인할 수 있었다. 3) 텍스트 마이닝과 구조적 등 위성 분석 결과 모두에서 지난 5년간 유튜브 이용자들로부터 가장 좋은 반응을 이끌어 낸 홍보 사업은 노년층을 위한 ‘디지털 리터러시’ 사업으로 나타났다. 4) 스팸 방지와 중고폰 보상 제도와 같은 미디어 이용자 보호 및 혜택 부여와 관련된 홍보 사업들은 유튜브 이용자들에게 긍정적인 평가를 받았다. 반면에, 장애인 미디어 접근성 홍보, 미디 어 관련 직업 소개, 지역 광고 활성화와 같은 사업들은 방통위의 주요 홍보 담론에는 포함 되었지만 주요 이용자 담론에서는 언급되지 않았다. 5) ‘할담비’, ‘팽수’, 그리고, ‘박말례 할머니’와 같이 인기 있는 기존 유튜브 캐릭터를 활용한 사업이 이용자들의 주요 담론에 큰 영향을 미칠 가능성이 높음을 확인하였다.

This study aims to provide strategic recommendations for effective promotional activities by comparing the YouTube content and user responses of the Korean Communications Commission (KCC), a national administrative agency. The research involved analyzing the titles and descriptions of KCC's promotional videos to understand the promotional discourse formed on YouTube and comparing it with user discourse evident in comments. Data were collected in unstructured text format, comprising 504 video titles/descriptions and 8,114 comments posted on the 'Korean Communications Commission' YouTube channel from January 2018 to December 2022. Post data mining, the top 50 keywords in terms of frequency were extracted from each dataset and analyzed through CONvergence of iteration CORrealtion (CONCOR) analysis. The study also examined basic statistical analysis results, keyword frequencies, and TF-IDF analysis to assess the promotional effectiveness of the KCC's YouTube channel over the past five years and proposed strategies for more efficient YouTube policy promotion. The findings are as follows: 1) In terms of frequency and TF-IDF analysis results, while KCC focused on promoting its name and services, KCC’s YouTube channel users showed more interest in individual promotional project themes and related contents/characters. 2) Although the KCC's name was relatively less mentioned in user comments, CONCOR analysis revealed that the KCC's name formed a cluster with positive emotional language, indicating that KCC's YouTube promotional activities positively contributed to user perception of the institution. 3) Text mining and CONCOR analysis both showed that promotional activities for 'Digital Literacy' aimed at the elderly elicited the most positive response from YouTube users in the past five years. 4) Promotional activities related to media user protection and benefits, such as spam prevention and used-phone compensation programs, received positive evaluations from YouTube users. Conversely, improving media accessibility for the disabled, introducing media-realted jobs, and supporing local advertising were included in KCC's main promotional discourse but not in user discourse. 5) Utilizing popular existing YouTube characters such as 'Haldambi', 'Pengsoo', and 'Park Mal-rye Grandma' in PR contents was found to have the potential to have a significant impact on user discourse.

The personal data protection could be examined from two points of view, in other words, preparation for preliminary base and establishment of post supplementation. The infringement of personal data required compensation for damages and other post remedial measures of damages: Fundamental measure was demanded to block the infringement of personal data in advance and to require not only construction of legal system for private data protection but also enactment of basic laws. The legislation of personal data protection could be classified into three, in other words, integration, separation and individual area, etc: The legislation in Korea was based on separation because it was divided into public area and private area. On the other hand, the private area was based on individual area because it was regulated by individual laws. Both public area and private area had different governing laws and regulations to be difficult to regulate both areas legally and effectively and to create unconformity between laws and regulations. Therefore, the dual legislation was given a lot of criticism to let the Government as well as NGO make efforts to improve systems and lay a bill of the integrated personal data protection before the National Assembly. This study tried to compare existing laws about information & communications and to analyze advantages and disadvantages of the laws, and also tried to suggest reasonable improvement.

‘인류학’은 인간에 관한 모든 것을 통시적․공시적 관점에서 분석하고 연구하는학문으로, 연구의 대상, 범위, 방법에 따라 고고학, 민족학, 민속학, 사회인류학, 문화인류학, 인지인류학 등 다양한 하위 분과를 포괄한다. 인류학은 19세기 이후 학문적 체계화 과정을 거치면서 시대와 사회에 따라 다양한 연구 방법론을 발전시켜왔다. 사진과 영화의 등장과 발전, 특히 동시녹음, 비디오, 디지털 장비 등 영화 촬영기술의 발전은 인류학의 연구방법론은 물론 연구결과물의 형식에 있어서 커다란변화를 가져왔다. 한편, 학술(學術) 연구 분야에서 새로운 이론의 제시, 새로운 현상의 발견, 발명등 연구의 성과를 발표하고 공유하는 가장 일반적인 방법은 학술지(學術誌)를 통한것이다. 학술지의 원형적 시도는 17세기(마랭 메르센)까지 거슬러 올라가는데, 그일차적 기능은 학문적 발견에 대한 기록과 연구자의 지적 재산권 보호이며, 연구성과의 확산과 연구결과물의 보존도 학술지의 중요한 역할이다. 1665년 최초의 학술지 발간 이후 인쇄술과 출판 산업의 지속적 발전에 따라 학술지는 지금까지도 학문적 커뮤니케이션의 대표적 창구로 자리매김하고 있다. 하지만 1980년대 이후 급속도로 발전해온 디지털, IT, 정보통신기술의 발전과 보급은 학문적 커뮤니케이션에 새로운 현상과 패러다임을 등장시켰다. 본 논문에서는 ‘학문 및 연구 자료의 형상화’를 영화와 인류학의 관계를 중심으로 살펴보고, 오랫동안 문자 매체에 의존해 왔던 학술 커뮤니케이션이 2000년대이후 새로운 트랜스미디어 콘텐츠이자 플랫폼으로 등장한 ‘인터랙티브 다큐멘터리’ 에 의해 어떤 양상으로 진화하고 있는지를 살펴보고자 한다.

Anthropology is a study to analyse and research all about humanity in terms of both synchrony and diachrony. It includes such diverse disciplines as archaeology, ethnology, folklore, social anthropology, cultural anthropology and cognitive anthropology, according to study objects, categories and approaches. The anthropology has been developing various study methodology especially since 19th century when it had processed to be systemized as a full-fledged science. Along with introduction and development of photography and motion pictures, mainly the innovations in filming technology (such as real-time recording, video, digital, etc.), the anthropology faced a drastic changes in the form of the result of research as well as the approaching methods themselves. Meanwhile, the academic journal is the most general means to announce and share the result of a scientific research in terms of new theorization, revelation and invention. The chronological prototype of the journal might check back to the 17th century (Marin Mersenne), and the primary functions of an academic journal are to record scientific revelation and to protect researchers’ intellectual properties as well as to spread and conserve the results of researches. Owing to continuous development in printing technology and publication industry which have kept pace with the sciences since the first issue in 1665, the academic journal has held the most significant means in academic communications. However, a new phenomenon and paradigm have introduced in the field of academic communications in consequence of rapidly evolving digital and ICT technology since 1980s. This essay aims to examine the ‘visualization of research or academic data’ and the ‘evolution in academic communications’, mainly regarding the introduction of photographic and cinematic media in the field of anthropology (progressed since the 19th century) and how the academic communication, which has largely depended on text-based media for a long while, is evolving into, by means of the ‘interactive documentary’, a newly emerging trans-media contents and platform in the 2000s.

A conventional pseudorandom sequence generator creates only 1 bit of data per clock cycle. Therefore, it may cause a delay in data communications. In this paper, we propose an efficient implementation method for a pseudorandom sequence generator with parallel outputs. By virtue of the simple matrix multiplications, we derive a well-organized recursive formula and realize a pseudorandom sequence generator with multiple outputs. Experimental results show that, although the total area of the proposed scheme is 3% to 13% larger than that of the existing scheme, our parallel architecture improves the throughput by 2, 4, and 6 times compared with the existing scheme based on a single output. In addition, we apply our approach to a $2{\times}2$ multiple input/multiple output (MIMO) detector targeting the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) system. Therefore, the throughput of the MIMO detector is significantly enhanced by parallel processing of data communications.

In this paper, we propose a new modulation scheme called multi-coded variable pulse position modulation (MC-VPPM) for visible light communication systems. Two groups of signals (Pulse Width Modulation (PWM) and Pulse Position Modulation (PPM) groups) are multi-coded by orthogonal codes for transmitting data simultaneously. Then, each multi-level value of the multi-coded signal is converted to pulse width and position which results in not only an improved data rate, but also a processing gain in reception. In addition, we introduce average duty ratio and cyclic shift concepts in PWM through which dimming control for light illumination can be supported without any degradation in communication performance. Through simulation, we confirm that the proposed MC-VPPM shows a comparable BER curve and much greater achievable data rate than the conventional VPPM scheme using a visible light optical channel environment.

High data-rate underwater communications is demanded. This demand imposes stringent requirements on underwater communication equipment of phase-locked-loop (PLL). Phase noise in PLL is unwanted and unavoidable. In this paper, we investigate the PLL phase noise effect on high order QAM for underwater communication systems. The phase noise model using power spectral density is adopted for performance evaluation. The phase noise components considered in PLL are reference oscillator, voltage controlled oscillator (VCO), filter and divider. The filters in PLL noise are assumed to be second order active and passive low pass filters. Through simulation, we analyze the phase noise characteristics of the four components and then investigate the performance improvement factor of each component. Consequently, we derive specifications of VCO, phase detector, divider to meet performance requirement of high data-rate communication using QAM under phase noise influence.

0.5MHz-40MHz 대역 옥내 저압전력선 (220V) 임피던스를 측정하였다. 측정을 위해 벡터 회로망 분석기와 저압 전력선 결합 장치(coupling unit)를 이용하였다. 결합 장치를 T형 등가회로로 바꾸어, 전체 회로에서 얻은 산란계수를 이용하여 저압 전력선 임피던스를 구했다. 제안된 방법으로 실제 한국형 저층 연립 아파트에 대한 평균 임피던스를 측정하였고, 그 결과 평균 임피던스 약 $100{\Omega}$이었다.

The communications link in a space program is a crucial point for upgrading its performance by handling data between spacecraft bus and payloads, because spacecraft's missions are related to the data handling mechanism using communications ports such as a controlled area network bus (CAN Bus) and a universal asynchronous receiver and transmitter (UART). The NEXTSat-1 has a lot of communications ports for performing science and technology missions. However, the top level system requirements for the NEXTSat-1 are mass and volume limitations. Normally, the communications for units shall be conducted by using point to point link which require more mass and volume to interconnect. Thus, our approach for the novel communications link in the NEXTSat-1 program is to use CAN and serializer and deserializer low voltage differential signal (SerDesLVDS) to meet the system requirements of mass and volume. The CAN Bus and SerDesLVDS were confirmed by using already defined communications link for our missions in the NEXTSat-1 program and the analysis results were reported in this study in view of data flow and size analysis.

Journals published by the International Communications Association (ICA), including the Journal of Communications, play an important role in the field of communications research. Like scientific journals in many other disciplines, ICA journals tend to be dominated by publications from researchers based at American and British institutions. Using a novel multi-modal dataset that includes funding, funding networks, and open-access publishing, the study seeks to understand the factors that impact the dominance of US/UK-affiliated institutions. By analyzing 9,437 publications from six prominent journals of the ICA, this study reveals significant Western dominance, with US institutions and scholars leading in publication volume, citation rates, and funding resources. The study identifies a reinforcing cycle wherein Western funding and infrastructure consolidate influence in global academic dialogues. Notably, while this Western "monopoly of knowledge" is reinforced by access to resources and publication platforms, a recent decrease in Western citation dominance suggests a shift. The study concludes by advocating for enhanced support for non-Western scholars to foster diverse perspectives within global communication research.

최근 몇 년 동안 몇몇 환경에서 트래픽 패턴이 Poisson 패턴보다 Self-similar 패턴에 더 가깝다는 것이 입증되어 왔다. 본 논문에서는 이러한 Self-similar 확률과정의 정의 및 트래픽의 특성, 그리고 최근 논문들에서 보고된 사례에 대해서 고찰해 봄으로써, 실제의 이동전화 데이터 트래픽 특성에 적합한지를 응용하고자 한다.

The classical queuing analysis has been tremendously useful in doing capacity planning and performance prediction. However, in many real-world cases. it has found that the predicted results form a queuing analysis differ substantially from the actual observed performance. Specially, in recent years, a number of studies have demonstrated that for some environments, the traffic pattern is self-similar rather than Poisson. In this paper, we study these self-similar traffic characteristics and the definition of self-similar stochastic processes. Then, we consider the examples of self-similar data traffic, which is reported from recent measurement studies. Finally, we wish yon that it makes out about the characteristics of actual data traffic more easily.