• Journal of IKEEE
• /
• v.12 no.2
• /
• pp.95-101
• /
• 2008

In this paper, we study an optimum design of search synchronization structure for Baseband Modem to support ISO/IEC 18185-5 and 24730-2 Standard. For DSSS Modem, we design the code acquisition and tracking structure which are important in receiver operation, and examine the parameters to be considered. The data and PN chip transmission rates and processing gain of the proposed modem are 59.7 kbps, 30.521875 Mcps, and 27 dB, respectively. This indicates that the noise immunity of the proposed modem is 17dB better than IEEE 802.11b (Processing gain : 10dB). Therefore, we design the optimum structure for the modem search synchronization which is compatible to the proposed modem standard.

• Speech Sciences
• /
• v.11 no.3
• /
• pp.181-192
• /
• 2004

The metrical structures in orally produced the poetry were generally analyzed by accent, metre and syllable. The purpose of this study is to investigate of metrical structures of Korean modem poetry using computer implemented speech analysis system. Two famous poet's poems confidential talk, Miloe and 'A buddhist dance, Sungmu' were selected for prosodic analysis. The informant is 60 years old professor in major of Korean and French poetry. The syllable structures of poems were analyzed primarily by vowel timbers, which can classified compact and diffuse vowels according to the distance of F2-F1. The perception cues of consonants were analyzed by VOT and tensity features of articulation. Rhythm is classified by dactyl, anapest, trochee, spondee and iambic. As a result, syllable structures of Korean modem poetry were mainly CV and CVC and the reading times of each lines were 3-4sec for 12 and 15 syllables. Main metre of Korean modem poems constructed the Imbic and Anapest. The break of each lines were demarcated by grammatical structure or meaning rather than phonetic structures.

• Journal of the Institute of Convergence Signal Processing
• /
• v.5 no.4
• /
• pp.325-332
• /
• 2004

In this paper, we propose a new DSSS-QPSK baseband modem receiver structure. A general receiver consists of matched filter, do-spreader, and DLL(Delay Locked Loop). In this paper, the matched filter plays a role of the do-spreader using the structure similarities between the matched filter and the de-spreader. As a result of the new receiver architecture, we can reduce the computational expenses and get the simpler receiver structure. This result can be used as an important part in designing the high speed modem. And, through the computer simulation and the experiment with the proposed architecture, we show that the proposed receiver structure yields fast operation speed and simple overall architecture.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.16 no.6
• /
• pp.789-796
• /
• 2013

Next Generation Weapon system from the center of the platform to share information in real-time Network Centric Warfare(NCW: Network Centric Warfare) has been changed. Data link system is defined as a network. That is, all in real-time battlefield information is to enable sharing. Data link system is classified as a precision strike, Monitoring/control, control of a Patriot missile battery systems. These systems are most effective in a Joint warfare and precision strike. Data Link Systems(Data Communications) implementation is accomplished by using the KDLM(Korean Data Link Modem) and Radio Transceiver. KDLM is operated in conjunction with the legacy Radios(re-using fielded HF/VHF/UHF radio systems). In this paper, we describe in terms of KDLM system design. In this paper, the proposed design structure is how to effectively interact with legacy various radio. First, The results provide an analysis of that Dynamic TDMA system and apply modem structure. Radio characteristics data are necessary for an effective TDMA system design. This article analyzes the test results and describes the structure to improve the receive performance.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.3
• /
• pp.1387-1394
• /
• 2011

In this paper, a low-area symbol timing offset synchronization structure for WLAN Modem is proposed. Using CSD(Canonic Signed Digit) coefficients and CSS(Common Sub-expression Sharing) technique for the filter implementation, efficient structure for multiplication block can be obtained. Function simulation for proposed structure is done by using the preamble with timing offset. Through Verilog-HDL coding and synthesis, it is shown that the proposed symbol timing offset synchronization structure can be implemented with low-area semiconductor.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.15 no.12
• /
• pp.990-1001
• /
• 1990

This paper compared and analyzed trellis coding with modem, discussed the basic concepts of it's structure and design. Logical observation was made on estimation method of coding gain and effect of error coefficient for trellis coding with modem. A signal space was analyzed on multidimensional coding in voiceband modem and differentially trellis coding with modem. As a result, we has obtained that 16 points constellation is more efficient than 2 dimensional.

• Journal of Communications and Networks
• /
• v.13 no.1
• /
• pp.70-76
• /
• 2011

This paper presents the unified user equipment (UE) baseband modulation and demodulation (modem) hardware platform architecture to support multiple radio access technologies. In particular, this platform selectively supports two systems; one is HEDGE system, which is the combination of third generation partnership project (3GPP) Release 7 high speed packet access evolution (HSPA+) and global system for mobile communication (GSM)/general packet radio service (GPRS)/enhanced data rates for GSM evolution (EDGE), while the other is LEDGE system, which is the combination of 3GPP Release 8 long term evolution (LTE) and GSM/GPRS/EDGE. This is done by applying the flexible pin multiplexing scheme to a hardwired pin mapping process. On the other hand, to provide stable connection, high portability, and high debugging ability, the stacking structure is employed. Here, a layered board architecture grouped by functional classifications is applied instead of the conventional one flatten board. Based on this proposed configuration, we provide a framework for the verification step in wireless cellular communications. Also, modem function/scenario test and inter-operability test with various base station equipments are verified by system requirements and scenarios.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.21 no.7
• /
• pp.1777-1786
• /
• 1996

This paper describes theories and implementation techniques of a digital high-definition television(HDTV) modem based on 32-QAM for terrestrial broadcasting. We proposed a digital demodulation scheme and a symbol timing recovery structure based on the band edge component maximization(BECM) method. The adaptive equalizer has 256 complex taps to remove the multipath of delays ranging from -2.mu.s~+24.mu.s with a new T/2-spaced blind equalization algorithm. computer simulation results reveal that the proposed algorithm outperforms other conventional blind equalization algorithm a digital HDTV modem with 4.91MHz symobol rate is implemented by utilizing the proposed algorithms. All processings for modem operations such as demodulation, estimation of symbol timing phase error, adaptive equalization, and carrier recovery except IF signal processing and sampling phase control part of the AD converter are done in digital domain. Especially, the carrier recovery loop can track a carrier offset of upto .+-.350KHz.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.49 no.2
• /
• pp.31-38
• /
• 2012

In this paper, a low area timing synchronization structure for the IEEE 802.11a OFDM MODEM SoC is proposed. The timing synchronization block of the IEEE 802.11a OFDM MODEM SoC requires large implementation area. In the proposed timing synchronization structure, it is shown that the number of multiplication can be reduced by using the transposed direct form filter. Furthermore, implementation area of the proposed structure can be more reduced using CSD(Canonic Signed Digit) and Common Sub-expression Sharing techniques. Through Verilog-HDL coding and synthesis, it is shown that the 22.7 % of implementation area can be reduced compared with the conventional one.

• The Journal of Korean Medicine
• /
• v.21 no.3
• /
• pp.9-19
• /
• 2000

Objective : We proposed fundamental rules of prospective Korean Standard Classification of Diseases(Oriental Medicine). Methods : We analysed Korean Standard Classification of Diseases(Oriental Medicine)(established in 1994) in comparison with ICD-10 and Chinese Standard Classification of Disease(Traditional Chinese Medicine). Secondly, we analysed the diagnostic structure of Modem oriental medicine. Results : Korean Standard Classification of Diseases has an inappropriate writing structure, logical errors of classification, confusion of symptoms, 'bing', and 'zheng', inappropriate comparison of disease designations in oriental medicine and western medicine, and the ommission of important items. Secondly, we demonstrate the relations of 'bing' and 'zheng' in modem oriental medicine and disease designations in oriental medicine and western medicine. Conclusions : We propose the separate classification of 'bing' and 'zheng', the qualification of designated names, the structure of 'bing' and 'zheng' system, and a different writing method.