On Target Detection by Quantum Radar (Preprint)

Both Noise Radar and Quantum Radar, with some alleged common features, exploit the randomness of the transmitted signal to enhance radar covertness and to reduce mutual interference. While Noise Radar has been prototypically developed and successfully tested in many environments by different organizations, the significant investments on Quantum Radar seem not to be followed by practically operating prototypes or demonstrators. Starting from the trivial fact that radar detection depends on the energy transmitted on the target and backscattered by it, some detailed evaluations in this work show that the detection performance of all the proposed QR types in the literature are orders of magnitude below the ones of a much simpler and cheaper equivalent classica radar set, in particular of the NR type. Moreover, the absence of a, sometimes alleged, Quantum radar cross section different from the radar cross section is explained. Hence, the various Quantum Radar proposals cannot lead to any useful result, especially, but not limited to, the alleged detection of stealth targets.Comment: 12 pages, 6 figures, 11 equations, 62 References. Not submitted. A "negative" result is obtained and presented with full details. This resuly is deemed useful and interesting according to the teachings by Karl Poppe

Range limitations in microwave quantum radar

This work, written for engineers or managers with no special knowledge of quantum mechanics, nor deep experience in radar, aims to help the scientific, industrial, and governmental community to better understand the basic limitations of proposed microwave quantum radar (QR) technologies and systems. Detection and ranging capabilities for QR are critically discussed and a comparison with its closest classical radar (CR), i.e., the noise radar (NR), is presented. In particular, it is investigated whether a future fielded and operating QR system might really outperform an “equivalent” classical radar, or not. The main result of this work, coherently with the recent literature, is that the maximum range of a QR for typical aircraft targets is intrinsically limited to less than one km, and in most cases to some tens of meters. Detailed computations show that the detection performance of all the proposed QR types are orders of magnitude below the ones of any much simpler and cheaper equivalent “classical” radar set, in particular of the noise radar type. These limitations do not apply to very-short-range microwave applications, such as microwave tomography and radar monitoring of heart and breathing activity of people (where other figures, such as cost, size, weight, and power, shall be taken into account). Moreover, quantum sensing at much higher frequencies (optical and beyond) is not considered here

Waveform Design and Related Processing for Multiple Target Detection and Resolution

The performance of modern radar systems mostly depends on the radiated waveforms, whose design is the basis of the entire system design. Today’s coherent, solid-state radars (either of the phased array type or of the single-radiator type as air traffic control or marine radars) transmit a set of deterministic signals with relatively large duty cycles, an order of 10%, calling for pulse compression to get the required range resolution. Often, power budget calls for different pulse lengths (e.g., short, medium, and long waveforms with a rectangular envelope) to cover the whole radar range. The first part of the chapter includes the topic of mitigating the effect of unwanted side lobes, inherent to every pulse compression, which is achieved both by a careful and optimal design of the waveform and by a (possibly mismatched) suitable processing. The second part of the chapter deals with the novel noise radar technology, not yet used in commercial radar sets but promising: (1) to prevent radar interception and exploitation by an enemy part and (2) to limit the mutual interferences of nearby radars, as in the marine environment. In this case, the design includes a tailoring of a set of pseudo-random waveforms, generally by recursive processing, to comply with the system requirements

On the anti‐intercept features of noise radars

Robustness against Electronic Warfare/Electronic Defence attacks represents an important advantage of Noise Radar Technology (NRT). An evaluation of the related Low Probability of Detection (LPD) and of Intercept (LPI) is presented for Continuous Emission Noise Radar (CE‐NR) waveforms with different operational parameters, that is, “tailored”, and with various “degrees of randomness”. In this frame, three different noise radar waveforms, a phase Noise (APCN) and two “tailored” noise waveforms (FMeth and COSPAR), are compared by time–frequency analysis. Using a correlator (i.e. a two antennas) receiver, assuming a complete knowledge of the band (B) and duration (T) of the coherent emission of these waveforms, it will be shown that the LPD features of a CE‐NR do not significantly differ from those of any CE radar transmitting deterministic waveforms. However, in real operations, B and T are unknown; hence, assuming an instantaneous bandwidth estimation will show that the duration T can be estimated only for some specific “tailored” waveforms (of course, not to be operationally used). The effect of “tailoring” is analysed with prospects for future work. Finally, some limitations in the classification of these radar signals are analysed

Option prices, exchange market intervention, and the higher moment expectations channel: a user’s guide

A vast literature on the effects of sterilized intervention by the monetary authorities in the foreign exchange markets concludes that intervention systematically moves the spot exchange rate only if it is publicly announced, coordinated across countries, and consistent with the underlying stance of fiscal and monetary policy. Over the past fifteen years, researchers have also attempted to determine if intervention has any effects on the dispersion and directionality of market views concerning the future exchange rate. These studies usually focus on the variance around the expected future exchange rate—the second moment. In this paper we demonstrate how to use over-the-counter option prices to recover the risk-neutral probability density function (PDF) for the future exchange rate. Using the yen/dollar exchange rate as an example, we calculate measures of dispersion and directionality, such as variance and skewness, from estimated PDFs to test whether intervention by the Japanese Ministry of Finance had any impact on the higher moments of the exchange rate. We find little or no systematic effect, consistent with the findings of the literature on the spot rate as Japanese intervention during the period 1996-2004 was not publicly announced, rarely coordinated across countries and, in hindsight, probably inconsistent with the underlying stance of monetary policy.Options (Finance) ; Foreign exchange administration

Signal design and processing for noise radar

An efficient and secure use of the electromagnetic spectrum by different telecommunications and radar systems represents, today, a focal research point, as the coexistence of different radio-frequency sources at the same time and in the same frequency band requires the solution of a non-trivial interference problem. Normally, this is addressed with diversity in frequency, space, time, polarization, or code. In some radar applications, a secure use of the spectrum calls for the design of a set of transmitted waveforms highly resilient to interception and exploitation, i.e., with low probability of intercept/ exploitation capability. In this frame, the noise radar technology (NRT) transmits noise-like waveforms and uses correlation processing of radar echoes for their optimal reception. After a review of the NRT as developed in the last decades, the aim of this paper is to show that NRT can represent a valid solution to the aforesaid problems

La traduzione nell’era dell'IA: nuovi ruoli, nuove competenze, nuova formazione

This article examines the impact of Artificial Intelligence (AI), and in particular Neural Machine Translation (NMT), on the translation industry. AI has the potential to simplify and increase productivity and the quality of work, but it also has the potential to marginalise human labour, creating conflicting attitudes towards the adoption of technologies. What is certain is that profound changes are taking place in the way we work, in the roles of language professionals and in the very concept of translation. The language service providers that are likely to thrive are those that can transform themselves into specialists who manage work processes, know how to use and control machines, and understand that AI needs language data to evolve. Professionals should also demonstrate to be conscious interlingual communicators with linguistic sensitivity, intercultural awareness and creativity. Translators are becoming post-editors, transcreators, language data managers, multilingual communication consultants for different media or trainers of non-professional translators. Post-editing has become a convergent activity with human translation, and translators and students are increasingly using NMT, often integrated with computer-aided translation (CAT) tools. Translation professionals are therefore required to understand the evolution, characteristics and types of NMT systems, their potential and limitations, and to know and deal with the different fields of activity that are emerging. This raises the question of whether the translation and language training offered by universities and schools is still adequate, or how they should embrace the challenge of updating their curricula and study programs to meet the needs of the market

machining induced residual stresses in alsi10mg component produced by laser powder bed fusion l pbf

Abstract The adoption of metal powder-based laser process (L-PBF) for industrial applications continues to widen, due to an increasing knowledge on additive processes and the availability of new systems for industrial production. The use of L-PBF processes requires a deeper investigation and comparison on mechanical properties of conventional and additive parts. For instance, metal parts produced by L-PBF could require additional machining operations, which alter the stress state of additive components. In this work, the effect of machining operations on the residual stress state of an AlSi10Mg component produced by L-PBF is investigated by means of the semi destructive hole-drilling method

What do we Know About the Effects of Macroprudential Policy, De Nederlandsche Bank Working

Abstract The literature on the effectiveness of macroprudential policy tools is still in its infancy and has so far provided only limited guidance for policy decisions. In recent years, however, increasing efforts have been made to fill this gap. Progress has been made in embedding macroprudential policy in theoretical models. There is increasing empirical work on the effect of some macroprudential tools on a range of target variables, such as quantities and prices of credit, asset prices, and on the amplitude of the financial cycle and financial stability. In this paper we review recent progress in theoretical and empirical research on the effectiveness of macroprudential instruments. Keyword