• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.57-60
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• 1999

In many radio communication environments, there is a special component, called inter-symbol interference (ISI), mused by multipath time delay of signal and ISI components impose limitation of the data transmission rate. In this paper, we consider signaling pulse shapes, called partial response signaling (PRS), for minimizing the effect of ISI and show the improvement of performance by applying one of the partial-response signaling (PRS) pulses to two types of receiver system under dependent noise environments through the Monte-Carlo computer simulations.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.653-654
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• 2006

A Pre-emphasis transmitter for DRAM bus system has achieved 3.2Gbps/pin operation at 1.8V supply voltage with 0.18um CMOS process. The transmitter has 800MHz PLL to generate 4 phase clocks. The 4 phase clocks are used for input clock of PRBS and multiplexing. One tap pre-emphasis is used to reduce inter symbol interference (ISI) caused by channel low pass effects. The analog calibration makes the optimized driver impedance independent with the PVT variation.

• JSTS:Journal of Semiconductor Technology and Science
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• v.8 no.3
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• pp.193-199
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• 2008

A combined clock and data recovery (CDR) circuit with adaptive cancellation of data-dependent jitter (DDJ) is constructed in all-digital architecture which is amenable to deep submicron technology. The DDJ canceller uses an adaptive FIR filter to compen-sate for any unknown channel characteristic. The proposed CDR decreases jitter in the recovered clock since the DDJ canceller significantly cancels out incoming jitter caused by inter-symbol interference.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.6
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• pp.459-464
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• 2013

In this paper, we introduce a modulation code design problem where best selection of two-dimensional codewords are determined to reduce two-dimensional (2D) intersymbol interference (ISI) and interpage interference (IPI). Codeword selection problem is formulated as a quadratic integer programming model that minimizes intra- and inter-symbol differences subject to uniform symbol usage and minimal Hamming distance violations. Second integer programming model detects the occurrence of isolated pixel pattern in the selected codewords. The proposed models are applied to 4-level and 2-level 6/8 codes.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.11C
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• pp.1564-1572
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• 2004

UWB(Ultra Wide Band) under standardization for WPAN has a restriction in transmitting power because of interference with existing systems. To overcome the restriction, in this paper, we construct the MIMO(Multi-input-Multi-Output) channel using multi-transmit/receiver antennas and analyze the performance of the proposed system. In addition, through numerical simulation, we obtain the interference property among these antennas and analyze the effect of an interference to the system. The proposed UWB system has a ML detector and the least square method will be used to cancel the multi-user interference and the inter symbol interference caused by multipath.

• ETRI Journal
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• v.27 no.3
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• pp.257-266
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• 2005

Many multi-modulus blind equalization algorithms (MMA) have been presented in the past to overcome the undesirable high misadjustment exhibited by the well-known constant modulus algorithm. Some of these MMA schemes, specifically tailored for quadrature amplitude modulation (QAM) constellations, have also been proved to fix the phase offset error without needing any rotator at the end of the equalizer stage. In this paper, a new multi-modulus algorithm is presented for QAM signals. The contribution lies in the technique to incorporate the sliced symbols (outcomes of decision device) in the multi-modulus-based weight adaptation process. The convergence characteristics of the proposed sliced multi-modulus algorithm (S-MMA) is demonstrated by way of simulations, and it is shown that it gives better steady-state performance in terms of residual inter-symbol interference and symbol-error rate. It has also been shown that the proposed algorithm exhibits lesser steady-state misadjustment compared to the best reported MMA.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.3C
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• pp.189-194
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• 2007

This paper derives and computes the detection probability of timing synchronization in an orthogonal frequency division multiplexing (OFDM) system encountered with a multipath Rayleigh fading channel and imperfect noise estimation. The timing synchronization scheme using a simple repeated constant amplitude zero auto-correlation (CAZAC) training symbol and correlation techniques is adopted. With this provision, we focus on the numerical analysis for OFDM timing synchronization scheme employing a preadvancement technique to reduce the inter-symbol interference (ISI). For measuring system performance, the detection performance derived in the considered system is presented in a multipath Rayleigh fading channel.

• Journal of the Korea Computer Industry Society
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• v.3 no.1
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• pp.67-76
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• 2002

This thesis aims at the study of the receiving part of wireless modem for Mobitex, which are designed for two way massage services by using the network of wireless packet. This receiving part has the features of GMSK demodulation by using Gaussian filter, which has the co-amplitude in a better condition and narrowness bandwidth and high performance in BER, compared with existing MSK modulation. In case of BT=0.3, we designed this receiving part to reduce RF output power spectrum at received data of symbol demodulation and avoid inter symbol interference(ISI) so that we can apply this part to Mobitex network which are currently in service for wireless modem in domestic.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.9
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• pp.12-17
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• 2016

In the holographic data storage system (HDSS), the data regarding the volume of a storage medium are recorded and read by the page, and the transmission rate and storage capacity can be increased because of two-dimensional, page-oriented data processing; furthermore, the multi-level HDSS can store more than one bit per pixel. For this same reason, however, and unlike conventional data-storage systems, the HDSS is hampered by two-dimensional (2D) intersymbol interference (ISI) and interpage interference (IPI). Progress regarding the published papers on 2D ISI, which is more severe in the multi-level HDSS, continues; however, mitigation of both 2D ISI and IPI in terms of the multi-level HDSS has not yet been studied. In this paper, we therefore propose a 4-level balanced-modulation code that simultaneously mitigates 2D ISI and IPI.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.11C
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• pp.682-693
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• 2011

Energy spreading transform (EST) based modulation is an effective technique to combat frequency-selective fading in broadband wireless communication. It performs close to the inter-symbol interference (ISI)-free matched filter bound (MFB) only at the complexity of a linear detector. Originally, EST-based modulation has been proposed for QPSK. However, to fully utilize the capacity of multipath fading channels, higher-order modulations are also necessary. In this paper, we review the EST based modulation that has originally been proposed for QPSK and discuss its extension to 8 PSK and 16 QAM. The performance of the extended system is verified through simulation in Proakis B and 8-tap fading channel. The EST based modulation for 8 PSK shows the performance which is very close to MFB and the EST based modulation for 16 QAM shows the performance gap between its receiver and MFB.