• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.145-146
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• 2006

In this paper, when concurrent transmission and diversity reception at each relay are assumed to increase bandwidth efficiency in linear multihop system, we analyze interference due to concurrent transmission and verify it. In the interference-free environment, more diversity sources at each relay result in better performance [1][2]. However, interference degrades BER performance because accumulated and propagated interference power surpasses original data power. Therefore, if we use the result of this paper, we can make bandwidth efficiency increase as well as BER performance good in linear multihop system by considering concurrent transmission with reuse factor and developing the algorithm which determines the number of diversity source.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.28B no.5
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• pp.404-410
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• 1991

In this paper,a network interface unit of token-passing bus network and its driving software are implemented based on Mini-MAP. This network interface unit performs the function of MAC layer which is responsible for transmission and reception of frames as well as the management of logical ring. The driving software performs the management of data buffer and the report of errors, if ocoured, to the higher layer. Motorola MC68824 of is used as a TBC(Token Bus Controller) and Intel80186 as a CPU for network interface unit. The operation of network interface unit is verified by self-test which checks the functioning of TBC and CPU. In addition each module of driving software is tested to check the functions regarding transmission and reception of frames.

• Journal of Digital Contents Society
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• v.5 no.3
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• pp.171-175
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• 2004

In this paper, We applied CCI canceller to remove multi-user interference in co-channel environment and improved performance of TH PPM UWB-IR system. As a result, We could get reception performance that data transmission of high speed is available in small reception power applying CCI canceller. Also, We could get permission available channel capacity to maximum access number 40 in high speed transmission environment more than 100Mbps.

• 한국정보통신설비학회:학술대회논문집
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• 2008.08a
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• pp.125-128
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• 2008

In this paper, the Transport Protocol Experts Group(TPEG) transmission and reception system based on Digital Radio Mondiale(DRM) is implemented for traffic information services. DRM stands for the European radio broadcasting standard to bring AM radio into digital radio, designed to work at frequencies below 30MHz. DRM can offer various data services such as text messages and a slide show service as well as audio services. In spite of low datarate, the TPEG system on DRM has an advantage that the traffic information service system for whole country can be established because DRM can offer wider service ranges than terrestrial-digital multimedia broadcasting(T-DMB) and simply archive a single frequency network.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.1
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• pp.14-20
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• 2012

CoMP(Coordinated Multi-Point transmission and reception) refers to a cooperative transmission strategy to control the interference from adjacent base stations in cellular mobile communication systems, which efficiently enhances the data throughput of the systems. As the number of the base stations participating in cooperative transmission increases, however, a larger amount of information exchange to carry the CSI(Channel State Information) of the mobile terminals is required. In this paper, we propose a partial CoMP transmission method for systems under the constraint of finite feedback information data. This method selects candidates of base stations which can provide high efficiency gain when they participate in the CoMP set. To achieve this, the cooperative base station combination is constructed by considering the preferred base stations of users. The cooperative base station combinations are dynamically applied since the preferred base station combinations of users may be different. We perform computer simulations to compare performance of the non-CoMP, full-CoMP and partial CoMP in terms of the average throughput using finite feedback and demonstrate the performance improvement of the proposed method.

• Journal of Multimedia Information System
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• v.5 no.3
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• pp.155-162
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• 2018

Nowadays, the tracking technology of Quadrant Detector will become actual by new micro devices. Based on the past filed data of the reception experiment with COMETS satellite, we have studied on new device (AD8302, phase difference detector) was acquired and suspect its abilities. In 1998, we have developed a Quadrant Detector for mobile to track a weak signal from satellite on Ka band of COMETS. The Quadrant Detector is comprised of four dedicated feed components for reception under an environment of Nakagami - Rician fading, and one transmission and reception feed component. We were successful in receiving a 23 GHz beacon signal from ICE transponder of the COMETS and succeeded in tracking the satellite from a moving vehicle at speeds of approximately 10 ~ 20 Km/h on paved roads. In 2018, with new device AD8302, we have verified new QD system and performed a simulation, based on the past filed experiment. This new device shall be improving the tracking abilities from mobile body on the earth to the multimedia satellite.

• Proceedings of the Safety Management and Science Conference
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• 2002.05a
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• pp.121-127
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• 2002

In this paper, we propose traffic management support and evaluate the performance through simulation. We suggest traffic management routing protocol that can guarantee reliance according to not only reduction of the Network traffic congestion but also distribution of the network load that prevents data transmission. For performance evaluation, we analyzed the average data reception rate and network load, considering the node mobility. We found that in the mobile Ad Hoc networks, the traffic management service increased the average data reception rate and reduced the network traffic congestion and network load in Mobile Ad Hoc Networks.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.60 no.4
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• pp.262-266
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• 2011

In high data-rate communication systems, encryption/decryption must be processed in high speed. In this paper, we implement CCM security mode which is the basis of security. Specifically, we combine CCM with AES block encryption algorithm in hardware. With the combination, we can carry out encryption/decryption as well as data transmission/reception simultaneously without reducing data-rate, and we keep low-power consumption with high speed by optimizing CCM block.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.7
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• pp.613-621
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• 2016

This research connected network equipment, including CCTV, PAGA, IP-PBX, and Legacy, in order to enable the operation and configuration of internal IP-based network equipment in maritime plants and vessels, both in the field and from remote places, and to allow for the support of remotely controlling such equipment. It also realized an operating program for the integrated network equipment management system to enable the monitoring and control of equipment status, operation condition, and notifications from distant places. By applying the operating program to satellite stations and vessels sailing on the sea, a performance test was conducted to evaluate data loss and transmission/reception delay in the communication section between the land and vessels. As a result, this research verified the normal operation of CCTV control and of real-time monitoring and control of the network equipment, including PAGA, IP-PBX, and Legacy under the FBB and MVSAT environments. It was observed that the transmission of CCTV video images with a large volume of data as well as the transmission and reception of voice data were found to be slightly delayed, indicating the need to develop technology to compress and convert data for real-time transmission and reception.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.1
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• pp.41-48
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• 2020

Currently, the industry uses MODBUS communication method using RS485 as a communication method used when constructing distributed equipment and networks. However, this method has a rather good transmission and reception distance, but has a disadvantage of being a half-duplex communication method. Therefore, there is a great need for a full-duplex communication method that can simultaneously transmit and receive two-wire communications. Therefore, in this paper, we propose a new communication hardware equipment that can implement full-duplex communication method by communication signal level to overcome the disadvantage of communication speed. The proposed communication hardware is a structure that can transmit and receive at the same time on the same communication line in two equipments communicating in a two-wire system. The characteristic of this communication hardware is that the transmitter generates two-level signal for data transmission, but the receiver generates three-level electric signal according to the status of the transmission data generated by the receiver. The data transmission signal information of the receiver is present at the same time. Therefore, the receiving side can analyze the received signal based on the information on the current transmission signal and can analyze the signal only in the two communicating devices, so it can be seen that the communication security is very excellent.