• ETRI Journal
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• v.26 no.5
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• pp.405-412
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• 2004

MC-CDMA, a multicarrier (MC) modulation scheme based on code division multiple access (CDMA), is the most likely candidate for the next generation of mobile radio communications. The rate compatible punctured turbo (RCPT) coded hybrid automatic repeat request (HARQ) has been found to give improved throughput performance in a direct sequence (DS) CDMA system. However, the extent to which the RCPT HARQ improves the throughput performance of an MC-CDMA system has not been fully understood. In this paper, we apply the RCPT HARQ to MC-CDMA and evaluate by computer simulations its performance in a frequency selective Rayleigh fading channel. We found that the performance of RCPT HARQ MC-CDMA is almost insensitive to channel characteristics. The performance can be drastically improved with receive diversity combined with space-time transmit diversity. In addition, the comparison of RCPT HARQ MC-CDMA, orthogonal frequency division multiplexing, and DS-CDMA shows that under similar conditions the throughput of MC-CDMA is the best in a frequency selective fading channel.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.07a
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• pp.456-456
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• 2004

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.1
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• pp.72-80
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• 2012

Binary CDMA is a new standard technology for wireless communication developed by our country that makes high speed communications and good quality of services. In this paper we researched the design and implementation methods of a wireless CCTV System based on the Binary-CDMA technology that makes it freely installed in any place without cables and laying works. We implemented the hardware and software for the CCTV system and developed a Prototype Wireless CCTV system based on the Binary-CDMA technology.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.1
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• pp.33-38
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• 2012

As underwater channel is very complex and time-varying, don't supports good-quality for communication service. In this paper, a multi-carrier CDMA(MC-CDMA) system for the reliability and robust service in the underwater acoustic channel is proposed and analyzed for its performance. Applied variable rate algorithm to the proposed system gets a channel state information from relationship between SINR and user data-rate. Using channel state information make spectrum usage more efficient and overall system performance improved. In this paper, the performance of proposed system analyzed by simulation. And Pseudo-Random spread codes used in the system are discussed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.1
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• pp.201-209
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• 2000

In this paper, the bit error rate (BER) performance of Multicode DS/CDMA-BPSK communication system is investigated in the presence of multi user interference and Nakagami fading channel environments. The DS/CDMA-BPSK communication system adopts multicode technique to enhance the data transmission rate. Using the calculated BER performance, BER figures of Multicode DS/CDMA-BPSK communication system are shown to discuss the effect of the number of multi user interference, Nakagami fading index, and data transmission rate. From the results, the transmission rate of DS/CDMA-BPSK signal improve by adopting Multicode technique. And we know that the major parameter of BER performance degradation in Multicode DS/CDMA system is the effect of multi user interference than the fading depth.

• The Journal of the Korea institute of electronic communication sciences
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• v.1 no.1
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• pp.70-80
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• 2006

The large portion of communication service areas move from a legacy wire-line voice service to mobile data service. For the purpose of satisfaction on market need, many communication systems should be installed and upgraded based on a mobile wide-band transmission facility. Recently, large part of communication service is based on internet protocol by packet switch techniques and required new technologies such as multimedia processing, QoS achievement, and mobility managememobile communication network such as IS-95A/B and CDMA2000-1X. In this paper, I analyzed the network architecture and service provision methods. in CDMA2000-1X nt. In korea, a CDMA communication technique is standardized for digital mobile communication systems. By using the analysed results, I will extract an efficient method for network evolution and a core technique for next generation mobile communication network.

• Journal of Korea Society of Industrial Information Systems
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• v.9 no.2
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• pp.89-95
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• 2004

CDMA is the way that more than one users can share the time and frequency at the same time and connect with multiple access in mobile communication. Multiple Access is indispensible for mobile communication because the limited frequency is able to be used by many users in mobile communication. CDMA is also applied to home network, military, business and medical sectors. This paper, presents a users should share limited frequency resource. CDMA module implemented with 8-layer PCB which consists of the Slice-board circuit, keeping Radio frequency characteristics and a slot type connector.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.1
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• pp.16-21
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• 2005

In this paper, we analyzed performance of proposed system ad DS/CDMA GMSK system in rician fading environment. Also, we expected that proposed system with turbo code scheme is applicable system for voice, data and multimedia communication.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.345-347
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• 2006

In this paper, we study the robot controller design using the voice and data communication via CDMA(Code Division Multiple Access) mobile communication network. We design the robot remote controller using the three methods, telephone call speech recognition, DTMF (Dual Tone Multiple Frequency) realization, SMS(Short Message Service) transmission/reception way via CDMA mobile communication network. We investigate the validity and effectiveness of the proposed remote controller which applied to the mobile robot.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.8C
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• pp.663-669
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• 2012

To solve the energy problem and finding new growth engines, interest for the smart grid is increasing and related technologies are making great efforts to secure in the world. AMI (Advanced Metering Infrastructure) Among them is the first to be constructed and getting attention as a key component of smart grid. A fusion of various technologies in technology development and demonstration is underway on Jeju Island Smart Grid Demonstration Complex in Korea, and focusing on broadband power line communication technology infrastructure is actively underway in Korea Electric Power Corporation. AMI system using power line communication technology without building a separate communication lines are available for power supply lines, but communication is impossible in occurs because admission to the power company or the ideal infrastructure for communication is not considered. In this paper, we analyze the requirements to build AMI system using Binary CDMA and powerline communications technology, and design the basic communication protocol based on Binary CDMA, implement network management and relay feature. By doing so, ways to apply Ad-hoc Binary CDMA indigenous technology to the AMI system were derived, and could build a system to make use of Wired (PLC) and wireless (Binary CDMA) simultaneously.