21,266 research outputs found
Breaking the challenge of signal integrity using time-domain spoof surface plasmon polaritons
In modern integrated circuits and wireless communication systems/devices,
three key features need to be solved simultaneously to reach higher performance
and more compact size: signal integrity, interference suppression, and
miniaturization. However, the above-mentioned requests are almost contradictory
using the traditional techniques. To overcome this challenge, here we propose
time-domain spoof surface plasmon polaritons (SPPs) as the carrier of signals.
By designing a special plasmonic waveguide constructed by printing two narrow
corrugated metallic strips on the top and bottom surfaces of a dielectric
substrate with mirror symmetry, we show that spoof SPPs are supported from very
low frequency to the cutoff frequency with strong subwavelength effects, which
can be converted to the time-domain SPPs. When two such plasmonic waveguides
are tightly packed with deep-subwavelength separation, which commonly happens
in the integrated circuits and wireless communications due to limited space, we
demonstrate theoretically and experimentally that SPP signals on such two
plasmonic waveguides have better propagation performance and much less mutual
coupling than the conventional signals on two traditional microstrip lines with
the same size and separation. Hence the proposed method can achieve significant
interference suppression in very compact space, providing a potential solution
to break the challenge of signal integrity
SIM-DSP: A DSP-Enhanced CAD Platform for Signal Integrity Macromodeling and Simulation
Macromodeling-Simulation process for signal integrity verifications has become necessary for the high speed circuit system design. This paper aims to introduce a âVLSI Signal Integrity Macromodeling and Simulation via Digital Signal Processing Techniquesâ framework (known as SIM-DSP framework), which applies digital signal processing techniques to facilitate the SI verification process in the pre-layout design phase. Core identification modules and peripheral (pre-/post-)processing modules have been developed and assembled to form a verification flow. In particular, a single-step discrete cosine transform truncation (DCTT) module has been developed for modeling-simulation process. In DCTT, the response modeling problem is classified as a signal compression problem, wherein the system response can be represented by a truncated set of non-pole based DCT bases, and error can be analyzed through Parsevalâs theorem. Practical examples are given to show the applicability of our proposed framework
Printed Circuit Board (PCB) design process and fabrication
This module describes main characteristics of Printed Circuit Boards (PCBs). A brief history of PCBs is introduced in the first chapter. Then, the design processes and the fabrication of PCBs are addressed and finally a study case is presented in the last chapter of the module.Peer ReviewedPostprint (published version
The Beauty of Symmetry: Common-mode rejection filters for high-speed interconnects and balanced microwave circuits
Common-mode rejection filters operating at microwave frequencies have been the
subject of intensive research activity in the last decade. These filters are of interest for
the suppression of common-mode noise in high-speed digital circuits, where differential
signals are widely employed due to the high immunity to noise, electromagnetic
interference (EMI) and crosstalk of differential-mode interconnects. These filters can
also be used to improve common-mode rejection in microwave filters and circuits
dealing with differential signals. Ideally, common-mode stopband filters should be
transparent for the differential mode from DC up to very high frequencies (all-pass),
should preserve the signal integrity for such mode, and should exhibit the widest and
deepest possible rejection band for the common mode in the region of interest.
Moreover, these characteristics should be achieved by means of structures with the
smallest possible size. In this article, several techniques for the implementation of
common-mode suppression filters in planar technology are reviewed. In all the cases,
the strategy to simultaneously achieve common-mode suppression and all-pass behavior
for the differential mode is based on selective mode-suppression. This selective mode
suppression (either the common or the differential mode) in balanced lines is typically
(although not exclusively) achieved by symmetrically loading the lines with symmetric
resonant elements, opaque for the common-mode and transparent for the differential
mode (common-mode suppression), or vice versa (differential-mode suppression).MINECO, Spain-TEC2013-40600-R, TEC2013-41913-PGeneralitat de Catalunya-2014SGR-15
Single-Piece State-Space Behavioral Models for IC Output Buffers
In this paper enhancements of parametric behavioral models for the output buffers of digital ICs are explored. A model based on a single-piece structure, which offers improved accuracy in describing state transition events for arbitrary load conditions, is proposed. This model exploits the potentiality of local-linear state-space parametric relations. These relations can be effectively estimated from input-output port responses only, and provide better stability properties and improved efficienc
Color-decoupled photo response non-uniformity for digital image forensics
The last few years have seen the use of photo response non-uniformity noise (PRNU), a unique fingerprint of imaging sensors, in various digital forensic applications such as source device identification, content integrity verification and authentication. However, the use of a colour filter array for capturing only one of the three colour components per pixel introduces colour interpolation noise, while the existing methods for extracting PRNU provide no effective means for addressing this issue. Because the artificial colours obtained through the colour interpolation process is not directly acquired from the scene by physical hardware, we expect that the PRNU extracted from the physical components, which are free from interpolation noise, should be more reliable than that from the artificial channels, which carry interpolation noise. Based on this assumption we propose a Couple-Decoupled PRNU (CD-PRNU) extraction method, which first decomposes each colour channel into 4 sub-images and then extracts the PRNU noise from each sub-image. The PRNU noise patterns of the sub-images are then assembled to get the CD-PRNU. This new method can prevent the interpolation noise from propagating into the physical components, thus improving the accuracy of device identification and image content integrity verification
Digital implementation of the cellular sensor-computers
Two different kinds of cellular sensor-processor architectures are used nowadays in various
applications. The first is the traditional sensor-processor architecture, where the sensor and the
processor arrays are mapped into each other. The second is the foveal architecture, in which a
small active fovea is navigating in a large sensor array. This second architecture is introduced
and compared here. Both of these architectures can be implemented with analog and digital
processor arrays. The efficiency of the different implementation types, depending on the used
CMOS technology, is analyzed. It turned out, that the finer the technology is, the better to use
digital implementation rather than analog
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