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In this paper, we present analytical models for line impedance and the coupling coefficient in the presence of additional ground tracks. We use a variational analysis combined with the transverse transmission-line technique to model interconnect lines guarded by ground tracks. Using the proposed model, it would be possible for designers to reduce crosstalk in coupled lines and obtain desired line impedance, thereby ensuring optimum signal integrity. The results obtained are verified by full-wave simulations and measurements performed on a vector network analyzer. The proposed model may find applications in the design and analysis of high-speed interconnects. Index Terms--Crosstalk, finite-difference time-domain (FDTD), ground tracks, printed circuit board (PCB) interconnects, signal integrity, variational analysis.

In this paper, we study the effect of cochannel interference (CCI) on the performance of partially coherent BPSK and QPSK in uncorrelated L-branch equal-gain combining systems. We consider a generalized propagation model wherein the desired and interfering signals undergo Nakagami-m or Rician fading with different amounts of fading severity. Further, the interfering signals are assumed to be asynchronous symbol timing with the desired signal, so that the effect of cross-signal intersymbol interference (ISI) is taken into account. Using a convergent Fourier series method, we derive extensive analytical results for the average bit error probability and the SNR gain penalty caused by the interference signals for different signal-to-interference ratio levels. The numerical results presented in this paper demonstrate the system performance under very realistic propagation and detection conditions including CCI, carrier phase error recovery, cross-signal ISI, generalized fading channels, and AWGN. Hence our results are expected to be of significant practical use for such scenarios. Index Terms--Cochannel interference, intersymbol interference, generalized fading channels, carrier phase error, quazi-analytical simulation, equal-gain combining.

A simplified linear precoding scheme is examined for far-end crosstalk (FEXT) cancellation in very high bit-rate digital subscriber line (VDSL) downstream transmission. Findings reveal that the proposed scheme is less complex and is capable of alleviating the computational load at the initialization.

Greedy bit-adding and bit-subtracting algorithms are used for the determination of a set of transmit power spectra for the reduction of degradation caused by intercarrier interference. Findings reveal the efficiency of the algorithms in achieving better performance.

A family of biwindowed discrete multitone (DMT) transceivers is proposed for providing both subchannel spectral containment at the transmitter and spectral selectivity at the receiver. Findings reveal that the proposed system is successful in providing a considerable gain in the achieving bit rate in the presence of narrowband noise and crosstalk.

The statistical behavior of the arrayed-waveguide grating (AWG) is analyzed as the random phase error yields a filter transmission. The arrayed-waveguide grating (AWG) degrades in terms of crosstalk.

The analysis and design of a quasi-distributed multimode fiber refractometer array is presented. The main challenge in the design of a practical quasi-distributed sensor array proved to be in mitigation of otherwise pronounced cross-talk effects among the individual sensors in the network. The cross-talk effects originate from mode filtering properties and the strong mode excitation dependence on the multimode refractometer sensors that constitute the array. The introduction of mode conditioning based on fiber mode filters and mode mixers effectively reduced the cross talk to a negligible level while providing the desired sensor response at acceptable collateral losses to the network. A comprehensive experimental analysis was carried out to provide detailed insight into the multimode sensor array behavior and to obtain data necessary for an overall and effective network design. OCIS codes: 060.2370, 120.4820.

Inter-element acoustic crosstalk in capacitive micromachined ultrasonic transducer (CMUT) transducer arrays is analyzed and minimized by using function matrix approach to derive crosstalk cancellation signals. This technique relies on programmable waveforms and it yields a reduced crosstalk effect with no additional fabrication complexity.

The potential of an optical microring resonator array as a high-frequency ultrasound sensor is investigated. It is found that the effective area of the microring is close to the ring size implying that array operation is possible with minimal cross talk between elements and of great application in telecommunication.

We present a network architecture for the distributed utility max-min flow control of elastic and nonelastic flows where utility values of users (rather than data rates of users) are enforced to achieve max-min fairness. The proposed link algorithm converges to utility max-min fair bandwidth allocation in the presence of round-trip delays without using the information of users' utility functions. To show that the proposed algorithm can be stabilized not locally but globally, we found that the use of nonlinear control theory is inevitable. Even though we use a distributed flow-control algorithm, it is shown that any kind of utility function can be used as long as the minimum slopes of the functions are greater than a certain positive value. Though our analysis is limited to the single-bottleneck and homogeneous-delay case, we believe that the proposed algorithm is the first to achieve utility max-min fairness with guaranteed stability in a distributed manner. Index Terms--Absolute stability, delay systems, flow control, nonlinear systems.

This letter presents a linear crosstalk precoder for very-high-speed digital subscriber lines (VDSL) that has a low run-time complexity. A lower bound on the data rate of the precoder is developed, and guarantees that the precoder achieves near-optimal performance in 99% of VDSL channels. Index Terms--Crosstalk cancellation, digital subscriber lines (DSL).

Phase-coded optical correlation storage in photorefractive crystals, using a crossed cylindrical-collimating lens system, has been realized. It possesses the advantages of both storage and correlator. It can perform real time and fast selection of the information correlated to the input information from a great amount of stored information. In Zn:Fe:LiNb[O.sub.3] (0.03 wt. % Fe, 3 mol. % Zn), combining this rotational phasecoded multiplexing with angular multiplexing, 36 holograms have been successfully multiplexed and exactly identified in the same crystal volume. The cross talk and angular selectivity of such phase-coded multiplexing are discussed. OCIS codes: 050.1950, 050.1960, 090.2900, 090.7330, 160.5320.

A study to model an unshielded twisted wire pair (TWP) cable above-ground plane is presented. The TWP line is discretized into small sections of fine which are analyzed by the 3-D finite-element method in order to extract the equivalent multiport network suitable for circuit analysis. The method is compared with the theory of nonuniform transmission lines and with the method of moments. A set of experimental results is finally carried out in order to validate the calculations. Index Terms--Crosstalk, electromagnetic compatibility, electromagnetic field numerical computation, finite-element method (FEM), transmission lines, unshielded twisted wire pair.

The crosstalk performance of a one-dimensional (1-D) capacitive micromachined ultrasonic transducer (CMUT) array is analyzed by comparing the finite element calculations using a commercial package (LS-DYNA) and the experimental measurements in both conventional and collapsed modes. The results have shown that the LS-DYNA model can be used to accurately model the crosstalk in CMUT arrays under specific voltage bias and excitation conditions.

We examine signal degradation effects in fiber arrays from fiber-to-fiber coupling and from cross talk attributable to backscatter from the sample medium originating from adjacent fibers in the array. An analysis of coupling and cross talk for single-mode fibers (SMFs) operating at 1310 nm with different core diameters, interaction lengths, core center spacing, and numerical apertures (NAs) is evaluated. The coupling was evaluated using beam propagation algorithms and cross talk was analyzed by using Monte Carlo methods. Several multimode fiber types that are currently used in fiber image guides were also evaluated for comparative purposes. The analysis shows that an optimum NA and core diameter can be found for a specific fiber center separation that maximizes the directly backscattered signal relative to the cross talk. The coupling between fibers can be kept less than -35 dB for interaction lengths less than 5 mm. The calculations were compared to an experimentally fabricated SMF array with 15 [micro]m center spacing and showed good agreement. The experimental fiber array without a lens was also used in a coherent detection configuration to measure the position of a mirror. Accurate depth ranging up to a distance of 250 [micro]m from the tip of the fiber was achieved, which was five times the Rayleigh range of the beam emitted from the fiber. OCIS codes: 170.0170, 170.4500, 170.2150, 060.2350.

A study is conducted to derive nonlinear and linear state-space control models for a multichannel semiconductor optical amplifier (SOA). The model could accommodate any gain function of the form g(N(t)) and could be extended to include models for the electronic drive circuitry and more advanced robust design and control.

Distributed circuit models are proposed for single-walled carbon nanotubes (SWCNs) and SWCN bundles that are valid for all voltages and lengths and it can be used for circuit simulations and compact modeling. The improvements have increased as the cross-sectional dimensions are reduced and for global interconnects, bandwidth density can be improved by 40% if there is at least one metallic SWCN per 3-[nm.sup.2] cross-sectional data.

We fabricated a multilayered medium by a laminating process with pressure-sensitive adhesives. It was possible to reduce the thickness variations of both photosensitive layers and transparent layers by applying laminating films. This method is easy to use to pile up many layers for a multilayered medium. We fabricated twenty recording layers and demonstrated the capability to record with significant reading results. The recorded data in each layer were read out without crosstalk. We evaluated the signal-to-noise ratio and crosstalk between neighboring layers. It was found that the signal-to-noise ratio of a multi-layered medium was higher than 50 dB.

The effect of square-wave propagation along coupled coplanar waveguides (C-CPWs) is presented in this paper. Developed numerical tools combining full-wave calculations of the frequency-dependent guided-mode parameters and the network theory formalism enable the determination of port voltages under specified linear termination conditions. Propagation constants and characteristic impedances of coupled lines have been determined for fundamental guided modes using the spectral domain technique combined with Galerkin's procedure. The scattering matrix of the four-port structure has further been used for the calculation of port voltages. Analysis has been performed by taking into account the bi-mode operation resulting from the assumption of the ideal electrical connection of distributed ground plane conductors. Simulation results have been compared with experimental data, and very good agreement has been found, proving the usefulness of the developed numerical tools. Index Terms--Coplanar waveguides, coupling phenomena, printed circuit boards (PCBs), spectral domain approach (SDA).

An approach for the crosstalk effect description in coupled coplanar waveguides with ideally grounded central strip conductor (C-CPWGS) that, for the first time, takes into account nonideal grounding by means of multimode propagation is presented in this paper. The frequency-domain full-wave computations of modal eigenvectors and propagation delays combined with multiconductor transmission line equations have been employed to obtain near- and far-end crosstalk waveforms. Developed theory has been verified experimentally by comparison with results of the time-domain crosstalk measurement of selected test structures. A very good degree of coherence between numerically computed and experimentally measured data has been achieved. Index Terms--Coplanar waveguides, electromagnetic coupling, printed circuits.

This brief deals with the crosstalk minimization problem in an integrated routing resource assignment stage containing several operations between global routing and detailed routing. A two-step heuristic algorithm consisting of coarse assignment and detailed assignment is proposed. In coarse assignment, shield lines are planned based on the chromatic number of a light coarse coupling graph, and the assignment of segments that are longer than a predefined threshold is solved with semidefinite programming. In detailed assignment, a strategy based on a dynamic priority queue is introduced to mitigate common problems caused by sequential routing. Experimental results on a set of benchmarks show significant reduction in coupling length between sensitive segments compared to a prevalent bipartite-matching-based algorithm. Index Terms--Crosstalk, layout, routing, shield insertion, track assignment.

A simple, low-complexity, linear zero-forcing (ZF) crosstalk canceller is proposed for digital subscriber lines (DSL), upstream VDSL's performance enhancement. This design has a low complexity and no latency and does not suffer from error propagation.

A detailed derivation of the evolution equation of the amplitude of a cavity mode, coupled to a waveguide, starting from Maxwell's equations, is provided by using the reciprocity relations. Results confirm that detuning is estimated in the case of photonic crystal cavity, coupled to a photonic crystal waveguide, showing that it is significant especially, if the structure is used for filtering applications.

Various code patterns of a via-programming read only memory (ROM) cause significant fluctuations in coupling noise between bitlines (BLs). This crosstalk between BLs leads to read failure in high-speed via-programmable ROMs and limits the coverage of applicable code patterns. This work presents a content-aware design framework (CADF) for via-programming ROMs to overcome the crosstalk induced read failure. The CADF ROMs employ a content-aware structure and correspondent code-structure programming algorithm to reduce the amount of coupling noise source while maintaining nonminimal BL load for crosstalk reduction. A 256-Kb conventional ROM and a 256-Kb CADF ROM were fabricated using a 0.25-[micro]m logic CMOS process. The measured results ascertain that the read induced read failure is suppressed significantly by CADF. The CADF ROM also reduced 86.2% and 94.5% in power consumption and standby current compared to the conventional ROM, respectively. Index Terms--Code patterns, crosstalk, read only memory (ROM).

Although the selective ramp reset waveform having one reset period during one television (TV)-field has a higher contrast ratio than the conventional ramp reset waveform with eight reset periods, the address discharge using the selective ramp reset waveform in a stripe barrier rib is severely influenced by the crosstalk. This problem of crosstalk among the cells constitutes the main obstacle to the development of high-resolution alternating current plasma display panels (AC-PDPs). In this paper, a new driving waveform is proposed, which renders the address discharge stable by decreasing the crosstalk, in addition to reducing the background luminance. In order to compare the address discharge stability of the proposed waveform with that of the conventional ramp reset waveform, we investigated the address discharge time lag through the photo-waveform measurement of address discharge for three waveforms and measured the dark room contrast ratio. As shown in the results, without decreasing the contrast ratio or the change of the panel structure, the address discharge time lag was considerably improved by the proposed waveform. Index Terms--Addressing, plasma display panel, reset.

Altered phase velocity lines are a novel kind of parallel microstrip lines for high-speed interconnection of digital circuits, on which the crosstalk is reduced by the different phase velocities of propagation on the adjacent lines. In this paper, a design method is proposed to optimize the geometry sizes of the altered phase velocity lines. The measured results of a prototype altered phase velocity pair designed by the proposed method are presented to validate the design method. And the effects of the process variation are simulated to analyze the robustness of the prototype in fabrication. The altered phase velocity lines outperform the symmetric parallel microstrip lines in terms of the lower far-end crosstalk (FrdCtk) and the lower dielectric loss. This technique reduces the FrdCtk in the pair of the microstrip transmission lines and does not significantly improve the near-end crosstalk. The prototype works at the speed of 2 Gbps for low crosstalk digital signal transmission, while it can transmit the high-speed clock signal at 10.5 GHz, so the altered phase velocity lines are a useful supplementary to the existing low crosstalk interconnection concepts in the scenario that the parallel microstrips have to be placed closely on printed circuit board. Index Terms--Crosstalk, high-speed interconnection, microstrip, slow wave line.

Geometry scaling increases the relative effect of coupling capacitances on performance, power, and noise so that they need to be carefully taken into account during process development, characterization, and monitoring. In the last decade, charge-based capacitance measurements (CBCMs) have been widely used to estimate on-chip wiring and coupling capacitances because of their accuracy and simplicity. We provide a thorough theoretical and experimental study of CBCMs applied to the selective extraction of cross-coupling capacitances. We take a historical perspective starting from the original CBCM approach proposed by Chen et al. in 1996, and we present a new technique for crosstalk-based capacitance measurements (CTCMs). CTCMs improve the accuracy and usability of CBCMs while reducing the complexity of the test structures. We present the theory of CTCM, we provide experimental results demonstrating its improved accuracy, and we discuss its application to a wide range of process monitoring and testing tasks. Experimental results are used throughout the paper to support the discussion. Index Terms--Cross-coupling capacitance, interconnect capacitance, matching, process monitoring, test structure.

The use of scattering parameters (S-parameters) to characterize high frequency interconnects has widely been used in the signal integrity field and is now being accepted into the disk drive arena as the preferred modeling tool for write and read path interconnects. The motivating factor for the shift from traditional lumped circuit models to S-parameter models has been the increase in data rates which exceed 1 GB/s. S-parameter models are convenient because they can be used directly in several high end spice circuit simulators as 'black box' models. This paper will describe recent measurement techniques which make vector (VNA) network analyzer measurements possible for various interconnect structures up to 8.5 GHz. This paper will verify the results using time domain reflectometry (TDR) measurements of the same interconnect structures. Specific examples on signal losses, impedance, and coupling will be shown. Advances in achieving a broad range of differential impedances while maintaining high bandwidth will be demonstrated with idealized test structures. Index Terms--Crosstalk, impedance, magnetic recording, scattering parameters, time domain reflectometry, vector network analyzer.

We present an analysis of the performance limit of an adaptive multichannel free-space optical inter-connect based on a spatial light modulator (SLM). The SLM function is to provide an active alignment of the signal beam in the detector plane. A thorough cross-talk analysis based on the diffractive properties of an ideal SLM in an isoplanatic optical system is shown. We analyze the performance in terms of the bit-error rate (BER) due to cross talk between different channels in the optical interconnect for different alignment states and for different phase-modulation schemes. OCIS codes: 200.2610, 200.4650, 090.1970, 230.6120.

An approach for three-dimensional substrate impedance engineering of p(super -)/p(super +) Si substrate for mixed signal integrated circuit applications is presented. It is found that this technology require minimum intrusion to conventional Si CMOS processing, making them prectical and effective.