Object-oriented domain specific compilers for programming FPGAs

  • Flynn M.
  • Mencer O.
  • Morf M.
  • Platzner M.

Simplifying the programming models is paramount to the success of reconfigurable computing with field programmable gate arrays (FPGAs). This paper presents a methodology to combine true object-oriented design of the compiler/CAD tool with an object-oriented hardware design methodology in C++. The resulting system provides all the benefits of object-oriented design ...

A system model for feedback control and analysis of yield: A multistep process model of effective gate length, poly line width, and IV parameters

  • Beachy M.
  • Rietman E.
  • Roy A.
  • Whitlock S.
  • Willingham T.

We present a large system model capable of producing Pareto charts for several yield metrics, including effective channel length, poly line width, I-on and I-sub. These Pareto charts enable us to target specific processes for improvement of the yield metric(s), Our neural network model has an accuracy of 80% and ...

Dispersion-induced power penalties in millimeter-wave signal transmission using multisection DBR semiconductor laser

  • Lim C.
  • Nirmalathas A.
  • Novak D.
  • Smith G.

In this paper, we present a simple analytical model to characterize the effect of fiber chromatic dispersion when using a multisection distributed-Bragg reflector (DBR) semiconductor laser as a millimeter-wave optical transmitter in a millimeter-wave fiber-radio system. We characterize the dispersion penalty of the laser as a function of the laser ...

Analysis of sum-product decoding of low-density parity-check codes using a Gaussian approximation

  • Chung S.
  • Richardson T.
  • Urbanke R.

Density evolution is an algorithm for computing the capacity of low-density parity-check (LDPC) codes under message-passing decoding, For memoryless binary-input continuous-output additive white Gaussian noise (AWGN) channels and sum-product decoders, we use a Gaussian approximation for message densities under density evolution to simplify the analysis of the decoding algorithm. We ...

Design of capacity-approaching irregular low-density parity-check codes

  • Richardson T.
  • Shokrollahi M.
  • Urbanke R.

We design low-density parity-check (LDPC) codes that perform at rates extremely close to the Shannon capacity The codes are built from highly irregular bipartite graphs with carefully chosen degree patterns on both sides. Our theoretical analysis of the codes is based on {[}1], Assuming that the underlying communication channel is ...

A study on stray capacitance modeling of inductors by using the finite element method

  • Holmes T.
  • Yu Q.

Stray capacitance modeling of an inductor is essential for its RF equivalent circuit modeling and inductor disign. Stray capacitance determines an inductor's performance and upper frequency limit. In this paper, a method has been proposed for modeling the distributed stray capacitance of inductors by the finite element method and a ...

Bit-rate sensitivity of filter-bank-based VDSL transmission to timing errors

  • Cuvelier L.
  • Louveaux J.
  • Pollet T.
  • Vandendorpe L.

The performance degradation of filter-bank-based multicarrier transmission due to timing errors is investigated. The receiver is made of a fractionally spaced linear or decision-feedback equalizer designed for some sampling phase. The actual sampling phase is different and the impact of the difference on the performance is investigated. Sampling phase offset ...

DPSK versus pilot-aided PSK MAP equalization for fast-fading channels

  • Collings I.
  • Davis L.

This letter compares pilot-aided phase-shift keyed (PSK) and differential PSK (DPSK) modulation when using new maximum a posteriori joint channel estimation and equalization receivers with frequency-selective fast-fading channels, We conclude that pilot-aided PSK has superior bit-error rate performance in this case, Howerer, at low signal-to-noise ratio, performance is similar, and ...

Beam propagation method tailored for step-index waveguides

  • Doerr C.

We present a scalar beam propagation method (BPM) that is tailored for step-index waveguides. For many structures, especially periodic ones such as star couplers, it is many times faster than and avoids the spatial quantization of existing BPMs. It can handle large propagation angles but not very large effective index ...

Linear space-time multiuser detection for multipath CDMA channels

  • Huang H.
  • Papadias C.

We consider the problem of detecting synchronous code division multiple access (CDMA) signals in multipath channels that result in multiple access interference (MAI). It is well known that such challenging conditions may create severe near-far situations in which the standard techniques of combined power control and temporal single-user rake receivers ...

A new approach for asynchronous distributed rate control of elastic sessions in integrated packet networks

  • Abraham S.
  • Kumar A.

We develop a new class of asynchronous distributed algorithms for the explicit rate control of elastic sessions in an integrated packet network. Sessions can request for minimum guaranteed rate allocations (e.g., minimum cell rates in the ATM context), and, under this constraint, we seek to allocate the max-min fair rates ...

Optimised 2D multi-resolution method of moment for printed antenna array modelling

  • Citerne J.
  • Gillard R.
  • Legay H.
  • Loison R.
  • Piton G.

Modelling is presented of microstrip antenna arrays with an optimised 2D multi-resolution method of moment (MRMoM). A Chui-Haar 2D multi-resolution basis is used fur the expansion of surface currents, and a pseudo-Galerkin scheme is introduced to speed up the algorithm. It is shown that, for large structures, the MRMoM generates ...

Flip-chip interconnects for frequencies up to W band

  • Heinrich W.
  • Jentzsch A.
  • Richter H.

A flip-chip approach for millimetre-wave frequencies up to W band is presented. Key to high return loss at the interconnect is a small bump-pad area. This is accomplished by means of Au-electroplated bumps and thermocompression flip-chip bonding. The electrical characteristics of this mounting technique are verified by measurements on test ...

IP security - What makes it work?

  • Younglove R.

Businesses are giving a lot of attention to virtual private networks today because they allow replacement of traditional dial-up or leased lines with IP connections to more economically link branch offices and remote workers to corporate network resources. More importantly, by delivering cost-effective secure communications services, VPNs enable businesses to ...

Rate adaptive shaping for the efficient transport of data traffic in diffserv networks

  • De Cnodder S.
  • Elloumi O.
  • Pauwels K.

In this paper, we introduce the need for traffic shaping for the efficient transport of aggregate Internetworking traffic over Differentiated Services (DiffServ) networks. We propose a family of rate adaptive shapers (RASs) that aim at reducing the traffic burstiness. Although RASs can be used in either pure Best-Effort or any ...

Correctness and performance of the ATM ABR rate control scheme

  • Lee D.
  • Moh W.
  • Ramakrishnan K.

We study both correctness and performance of the source/destination protocols of the available bit rate (ABR) service in asynchronous transfer mode (ATM) networks. Although the basic protocol for rate-based congestion management is relatively simple, the protocol specification has to cope with several ``real-world{''} cases such as failures and delayed/lost feedback ...

Transient spectroscopy of tetracene single crystals

  • Batlogg B.
  • Frolov S.
  • Kloc C.
  • Schon J.

Ultrafast dynamics of photoexcitations in ultrapure tetracene crystals were studied using transient photomodulation spectroscopy. We measured characteristic transient absorption and stimulated emission bands of Frenkel excitons and found that efficient internal conversion to the lowest exciton and subsequent vibronic relaxation occurs within 200 and 500 fs, respectively. Exciton relaxation to ...

Role of interdimer interactions in NH3 dissociation on Si(100)-(2 x 1)

  • Chabal Y.
  • Queeney K.
  • Raghavachari K.

The dissociation of NH3 on Si(100)-(2 x 1) is investigated by a combination of infrared absorption spectroscopy and density functional cluster calculations, revealing that this reaction is governed by a complex set of interdimer interactions involving both bare and adsorbate-covered Si dimers. We propose that such adsorbate-induced changes in the ...

Coupling coefficient of a new circular eccentric iris for multimodal cavity filters

  • Baudrand H.
  • Dillenbourg H.
  • Herren J.
  • Surre F.
  • Vuong T.

In this paper, a new eccentric circular iris is introduces. It is designed to couple two cavities in bandpass filters. The frequency characterization is made by a mode-matching method. Experimental results are in good agreement with theoretical ones. The influence of the aperture radius on the coupling coefficient is also ...