• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.4
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• pp.20-29
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• 1998

In this paper, we find the values of near-end crosstalk coefficients in dual-offset stripline of a FR-4 multilayer PCB by an analytic method and a HSPICE simulation method, define calculation errors inananlytic method and the application range, simulate near-end crosstalk coefficients of the FCT(Fast CMOS TTL) in complicated dual-offset stripline by HSPICE and analyze near-end crosstalk and far-end crosstalk coefficients in dual-offset stripline. So, we analyze coupling structure of the near-end crosstalk and far-end crosstalk in the complicated dual-offset striplines that are 1[pF] capacitors termainated, and define a coupling formula of near-end crosstalk and far-end crosstalk coefficients dual-offset striplines.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.2
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• pp.35-42
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• 2010

In this study, crosstalk between dominant interconnect pairs in an A/D converter circuit is analyzed in frequency domain and effects of termination conditions on crosstalk are described, based on the practical circuit conditions. An A/D converter circuit is a mixed circuit where both clean and noisy signals coexist such that the circuit probably suffers from distortion by crosstalk. An analog input signal and the reference voltage signal, which dominate the overall conversion performance of the A/D converter circuit, are ready to be distorted by crosstalk and include specific termination conditions, such as non-matching and capacitive termination, respectively. Thus, this study presents the model of crosstalk considering impedance mismatch at both ends and analyzes effects of the practical termination conditions in the analog input and the reference voltage interconnects on crosstalk. A typical circuit configuration of the two interconnects is described and crosstalk including near-end and far-end termination impedances is modeled. Effects of the near-end impedance mismatch in the analog input interconnect and the far-end capacitive termination in the reference voltage interconnect are estimated in the frequency domain by using the model of crosstalk and experiments are performed to confirm the estimated results. Microstrip lines are used as interconnects, involving the increase of loss in high frequencies.

• Journal of Electrical Engineering and Technology
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• v.11 no.1
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• pp.175-183
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• 2016

This paper brings out a novel method for reducing Near end and Far end Crosstalk using Electromagnetic Band Gap structures (EBG) in High Speed RF transmission lines. This work becomes useful in high speed closely spaced Printed Circuit Board (PCB) traces connected to multi core processors. By using this method, reduction of −40dB in Near-End Crosstalk (NEXT) and −60 dB in Far End Crosstalk (FEXT) is achieved. The results are validated through experimental measurements. Time domain analysis is performed to validate the signal integrity property of coupled transmission lines.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.7
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• pp.774-783
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• 2012

In this paper, a periodically corrugated transmission line is proposed. The proposed transmission line can reduce crosstalk between transmission lines. The corrugated transmission line can adjust the amount of inductive coupling and capacitive coupling equally. Thus, the crosstalk is effectively reduced because the inductive coupling and capacitive coupling cancel each other. The corrugated transmission line is fabricated on RO4003 substrate with a dielectric constant of 3.38 and a thickness of 0.508 mm. The simulated far-end crosstalks of conventional transmission line and corrugated transmission line with a period of A=1 mm have maximum values of -3.6 dB and -22 dB, respectively, up to 30 GHz. Measurement results showed that far-end crosstalks of the conventional and corrugated transmission line have maximum values of -6.3 dB and -20.5 dB, respectively, up to 30 GHz.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.523-526
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• 2002

The crosstalk among coupled microstrip lines is the major limiting factors of signal qualities in the high-speed digital and communication equipment. In this paper, a three-dimensional finite difference time domain (FDTD) method is applied to analyze the crosstalk between the coupled microstrip lines. The proposed structures of the coupled microstrip lines are investigated to reduce the coupling in a simple way by modifying their ground plane with an optimum gap. The examples of these structures with the different sizes of the gaps on their ground plane are studied. These structures are considered as the four-port network to evaluate transmission efficiency, near- and far-end crosstalk. Gaussian pulse is excited to evaluate the frequency characteristics from dc to 30 ㎓. The transmission efficiency, near- and far-end crosstalk of each structure of the coupled microstrip lines are demonstrated. The numerical results of this study show that the majority of crosstalk is the far-end crosstalk. The usage of the optimum gap on the ground plane can reduce the far-end crosstalk of the coupled microstrip lines while the transmission efficiency is nearly equal.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1878-1881
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• 2002

The capacitance of nonlinear component such as a CMOS inverter varies largely around the threshold voltage. We measured the far-end crosstalk of two parallel microstrip lines with the CMOS inverter load near the threshold voltage of the CMOS inverter, The negative voltage of the crosstalk agrees with that for a 4pF capacitor toad. The positive voltage of the crosstalk hardly changes of the amplitude of the input step voltage.

• Journal of IKEEE
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• v.23 no.3
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• pp.1046-1053
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• 2019

In a multi-channel single-ended system, the far-end crosstalk (FEXT) due to mutual inductance and mutual capacitance between two adjacent channels critically limit the bandwidth. FEXT causes crosstalk-induced jitter (CIJ) and crosstalk-induced glitch (CIG) which leads to timing margin and voltage margin degradations, respectively. Therefore, FEXT must be compensated in order to increase eye opening and achieve high data-rate. It can be compensated in transmitter by controlling the timing of the data or reshaping the waveform of the signal. Also, FEXT can be compensated in receiver by generating mimicked FEXT using high-pass filter. In this paper, recent techniques to compensate FEXT are investigated, with discussions of their pros and cons.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.8
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• pp.16-25
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• 1994

The prediction of crosstalk in one of important problems in estimating the EMC of a system for high speed digital signal transmission. Crosstalk curves are shown in terms of characteristic impedance of lines spacing between lines and rise time of pulse by using general multiple coupled transmission line equation and harmonic-balance method. The coupled symmetrical two-line on dielectric material epoxy-glass FR 4(${\varepsilon}_r$), is fabricated to measure crosstalk occuring at the near end and far end of the passive line. The inter-line is inserted to reduce crosstalk between two microstrip lines. The simulation results and the measurement results are shown and found to be very close.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.1
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• pp.79-85
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• 1999

The propagation properties of the high speed pulse signal in time domain using the equivalent circuits for the analysis by SPICE on the coupled microstrip lines are investigated. In this paper, the SPICE program is used for the crosstalk analysis on the coupled microstrip lines. The results of crosstalk of coupled microstrip lines compared to one by Branin and FDTD method. And the near-end and far-end crosstalk on coupled lines are analyzed for the square pulse and trapezoidal pulse. The results of this paper are apply To the determination for the geometric structure and the frequency of signal pulse in design of MIC and MMIC by the CAD program.

• Information and Communications Magazine
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• v.16 no.10
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• pp.112-124
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• 1999

본 논문에서는 FTTC/VDSL (Fiber-to-the-Curb/Very High-speed Digital Subscriber Line) 전송시스템의 개발동향과 ANSI, ETSI, ITU등의 표준화 위원회에서 현재 진행중인 VDSL 시스템의 표준화 작업에 대해 기술하였다. 특히, POTS (Plain Old Telephone Service), BA-ISDA(Basic Access Integrated Services Digital Network), HDSL(High-rate Digital Subscriber Line), SDSL (Single-pair HDSL), ADSL(Asymmetric Digital Subscriber Line) 등의 다양한 xDSL (Digital Subscriber Line) 서비스들에서 발생하는 NEXT (Near-end Crosstalk)/FEXT (Far-end Crosstalk)와 같은 crosstalk를 최소화하기 위해 제안된 VDSL시스템의 주파수 대역과 PSD (Power Spectral Density) mask에 관해 설명하고, 순방향(down-stream) 채널과 역방향(upstream) 채널의 데이터 전송률이 대칭적인 VDSL전송시스템과 비대칭적인 VDSL 전송시스템 간의 주파수대역의 호환성 문제, RFI(Radio Frequency Interference) ingress/egress 문제의 해결 방안에 관해 기술하였다. 또한, 현재 VDSL Coalition과 VDSL Alliance 간에 논의 중인 VDSL 전송시스템의 변복조 방식에 관한 표준화 작업과정 및 순방향과 역방향에 할당될 band 개수에 따른 시스템 성능의 장단점 등에 관해 살펴보았다. 끝으로 현재 국내에서 개발되고 있는 FTTC/VDSL 전송시스템의 전체구조를 요약하고, 네트워크에서 가입자쪽으로 순방향 데이터 전송에 사용된 51.84 Mb/s 19-CAP (Carrierless Amplitude/Phase Modulation) 전송시스템과 가입자 댁내에서 네트워크 방향으로 역방향 데이터 전송에 사용된 1.62 Mb/s QPSK (Quadrature Phase Shift Keying) burst-mode TDMA (Time Division Multiple Access) 전송시스템 등의 동작 원리 및 구조를 기술하였다.