Active Attack on User Load Achieving Pilot Design in Massive MIMO Networks

In this paper, we propose an active attacking strategy on a massive multiple-input multiple-output (MIMO) network, where the pilot sequences are obtained using the user load-achieving pilot sequence design. The user load-achieving design ensures that the signal-to-interference-plus-noise ratio (SINR) requirements of all the users in the massive MIMO networks are guaranteed even in the presence of pilot contamination. However, this design has some vulnerabilities, such as one known pilot sequence and the correlation among the pilot sequences, that may be exploited by active attackers. In this work, we first identify the potential vulnerabilities in the user load-achieving pilot sequence design and then, accordingly, develop an active attacking strategy on the network. In the proposed attacking strategy, the active attackers transmit known pilot sequences in the uplink training and artificial noise in the downlink data transmission. Our examination demonstrates that the per-cell user load region is significantly reduced by the proposed attacking strategy. As a result of the reduced per-cell user load region, the SINR requirements of all the users are no longer guaranteed in the presence of the active attackers. Specifically, for the worst affected users the SINR requirements may not be ensured even with infinite antennas at the base station.Comment: Accepted in IEEE GlobeCOM 201

Scoring Millennium Goals: Economic Growth Versus the Washington Consensus

According to the IMF and the World Bank, "on current trends, most Millennium Development Goals (MDGs) will not be met by most countries." This assessment of a joint report of the staffs of the Bank and Fund issued in 2004 is widely shared, including by a UN report that came out at the beginning of 2005. The joint Bank-Fund report identifies the first of "the three essential elements" urgently needed if most countries are to reach the MDGs as: "Accelerating reforms to achieve stronger economic growth – Africa will need to double its growth rate." The other two pertained to the more and better delivery of human development and related services and of support from developed countries and international agencies. All these three elements have also been emphasized by the UN report, which paid particular attention to the case for increasing aid

Good Growth and Governance for Africa: Rethinking Development Strategies: Introduction and Overview

When the countries of Sub-Saharan Africa achieved independence in rapid succession starting with Ghana in 1957, there were high hopes for the region. A group of outstanding leaders would inspire to bring a new era to a sub-continent long suffering from colonial exploitation and developmental neglect. What has happened since has been disappointing: whilst standard economic theory predicts a convergence in economic outcomes, with those countries with lower per capita incomes growing faster than those with higher, there has been divergence, particularly for Sub-Saharan Africa, with incomes per capita in the region stagnating over 1960-2000 (as the gains of the first two decades of that period were wiped out in the next two) and poverty increased when in the rest of the world per capita incomes more than doubled and in some of the most successful developing countries increased four-fold or more (see the figures in Section II). Only the few years before the global economic crisis of 2008 brought respite to this picture of gloom for Africa, as annual growth soared to some 6% during 2006 and 2007, with only the East and South Asian regions exceeding it by a significant margin, but even this period of optimism appears fragile and built on soaring resource prices as much as anything else. This naturally raises the question: Why has the economic growth performance of Sub- Saharan Africa (hereinafter Africa) been so disappointing and more to the point, what are the policy options for reversing that trend? What are the possibilities and policies for Africa to achieve sustained, rapid economic growth and associated structural transformations and begin to catch-up

Learning, Industrial, and Technology Policies: An Overview

Many of the most fundamental and frequent controversies in economics revolve around two related sets of issues: the salience and significance of market failures and the role of the state in overcoming them. They arise in a particularly acute form in the literature on industrial policies. Broadly understood, industrial policy refers to public policy measures aimed at influencing the allocation and accumulation of resources, and the choice of technologies. A particularly important set of industrial policies, at the center of many of the chapters in this volume, comprises those targeted at activities that promote learning and technological upgrading. They are sometimes more accurately labeled as learning, industrial and technology (LIT) policies. We use the term to cover both deliberate and self-described industrial policies as well as policies that have a similar effect though they are not labeled as “industrial policies” (this is particularly well illustrated by Antonio Andreoni's contribution, chapter 9)

Introduction and Overview: Economic Transformation and Learning, Industrial, and Technology Policies in Africa

This chapter is an introduction and overview of "Industrial Policy and Economic Transformation in Africa." The main objective of the contributions in this volume is to shed light on how to vigorously promote economic transformation. They emphasize the vital role of industrial policies. It is perhaps noteworthy that the two economies among the fastest-growing in Africa in this century did not rely on an oil boom: Ethiopia and Rwanda pursued to varying degrees deliberate policies of government interventions of the type we label industrial policies. These two countries were consciously and explicitly influenced by the successful experiences with industrial policies of the most successful East Asian countries (see World Bank 1993; Stiglitz and Uy 1996). We provide a quick overview of Africa's development experience in the next three short sections in order to provide a context for the two longer ones concerning the main themes of this volume. "Static Efficiency vs. Dynamic Gains: Learning, Industrial, and Technology Policies" examines the need and possibilities of learning, industrial, and technology policies in the region, and the last section provides an overview of the other chapters in this volume and how they contribute to that aim

Innovative Financing for Infrastructure in Low Income Countries: How Might the G20 Help?

Among the outcomes of the Group of 20 (G20) Seoul Summit in November 2010 was an enhanced focus on development, especially infrastructure in low-income countries (LICs). The comprehensive work program that emerged included the establishment of a High-Level Panel for Infrastructure Investment to report to the forthcoming summit in France. Many of the actions for infrastructure development will take time to bear fruit. The aims of this think-piece are to propose some ways of responding to the G20’s initiative. One such response could comprise mobilizing innovative financing that uses the large and growing savings surpluses of some countries, often held in sovereign wealth funds (SWFs); providing those resources to LICs on appropriately concessional terms; using those resources to encourage private investments; and beginning to use the monies quickly while measures to scale up their use are taken. This document is more of a think-piece than a blueprint, and as such does not address all details of design and implementation. It does, however, pay particular attention to the region of Sub-Saharan Africa, where most LICs are and where LICs generally have worse infrastructure than LICs elsewhere. Overcoming infrastructure shortfalls is expected to have a large impact on the region’s economic growth, with significant implications for employment and poverty