A single Chip Implementation for Fast Convolution of Long Sequences

Usually, long convolutions are computed by programmable DSP boards using long FFTs. Typical operational requirements such as minimum power dissipation, minimum volume and high dynamic range/accuracy, make this solution often inefficient and even unacceptable. In this paper we present a single chip floating point solution for large convolution problems. It is based on an algorithm that maps long convolutions on short FFTs without affecting the optimum complexity O(N log N). The chip contains a highly parallelized short length FFT core enabling us to compute an FFT completely, without external FFT working memory intervention. The FFT core contains a set of fully parallelized radix 2 processing cores based on a hybrid floating point data format. The proposed implementation of the arithmetic blocks is the result of a trade off between maximum accuracy, maximum dynamic range and minimum chip area. The convolution chip will be used in a realtime Synthetic Aperture Radar (SAR) imaging processor developed for on-board aircraft or satellite processing

Real options in an asymmetric duopoly: who benefits from your competitive disadvantage?

This paper analyzes the impact of investment cost asymmetry on the optimal real option exercise strategies and the value of firms in duopoly. Both firms have an opportunity to invest in a project enhancing (ceteris paribus) the profit flow. We show that three types of equilibrium strategies exist. Furthermore, we express the critical levels of cost asymmetry delineating the equilibrium regions as functions of basic economic variables. The presence of strategic interactions among the firms leads to counterintuitive results. First, for a certain range of the asymmetry level, a marginal increase in the investment cost of the firm with the cost disadvantage can enhance this firm's own value. Moreover, such a cost increase can reduce the value of the competitor. Finally, we discuss the welfare implications of the optimal exercise strategies and show that the presence of identical firms can result in a socially less desirable outcome than if one of the competitors has a significant cost (dis)advantage

Competition schemes and investment in network infrastructure under uncertainty

Service-based competition, Facility-based competition, Real options, Preemption, D92, G13, L43, L51,

R&D Investments with Competitive Interactions

In this article we develop a model to analyze patent-protected R&D investment projects when there is (imperfect) competition in the development and marketing of the resulting product. The competitive interactions that occur substantially complicate the solution of the problem since the decision maker has to take into account not only the factors that affect her&his own decisions, but also the factors that affect the decisions of the other investors. The real options framework utilized to deal with investments under uncertainty is extended to incorporate the game theoretic concepts required to deal with these interactions. Implementation of the model shows that competition in R&D, in general, not only increases production and reduces prices, but also shortens the time of developing the product and increases the probability of a successful development. These benefits to society are countered by increased total investment costs in R&D and lower aggregate value of the R&D investment projects. Copyright 2004, Oxford University Press.