Quantum Signal Processing: How do you level up the Playing Field?

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So, who thinks they know what is on offer from Quantum Computers augmenting 5G systems? Who knows what a Quantum Fourier Transform actually is? (And I don't mean just looking it up on Wikipedia?). Well, the honest answer is: probably no-one. Yet. But some more than others provided they know the strengths and weaknesses of the DFT/FFT and the current workarounds employed.

Digressing (slightly) for a moment, it has been said that “England and America are two nations divided by a common language”. So true. Alas it is claimed both share Common Values, but what usually goes unstated regards the statement of a Common Purpose. Never, ever has there been common purpose between the John Milton Brigade and the Founding Fathers. Whereas the Common Purpose of the EU is the ever closer union of its peoples (including the peoples of the UK) in order to prevent another European conflagration. Enough is enough when it comes to European Wars. Hence, the serious question that is not being posed is: what is the common purpose of the US and England now? And I deliberately mean England not the UK of GB and NI.

What has all this to do with Quantum Computers and 5G and eventually Quantum Radars down the line? Well, as some readers shall know the 3GPP is advancing a decision on Release 15 to December, this year, that is 2017. This path, of course, should not be confused with the agenda for the IMT-2020 via the ITU-R where working parties for WRC-19 are also well underway. No dithering or delay here. Also as most readers shall know by now, IBM, that most American of corporations, founded of course by a Scot, has begun a collaborative marketing exercise through enabling free access to their next generation QC processors hosted via their IBM Cloud. The catch being that it is for selected (by IBM that is) parties only. Oh Dear! Funny is it not how there is always a catch with free access to anything.

IBM's worthy intention being to address the creation of an online commercial business community, but without a business payment model or real-time settlement vehicle to coalesce around as yet. Previously these QC technologies have been within the domain of heavy duty academics, and the province of the defence and intelligence community. Therein IBM are upping their Qubit count to currently 16Qubit and 17Qubit processors respectively. With the goal of commercial 50Qubit processors being available in under 5 years. Their preferred software interface being Python. But shall they sell the finished products to Alphabet, Amazon, Apple or FaceBook or even the national network providers or instead just sell privileged serviced access instead? Incidentally, does Oddness and Evenness matter in Quantum Fourier Analysis? What about Superposition even?

The best exposition (believable that is) White Paper I have come across to date on 5G is from the mighty SkyWorks Solutions “5G in Perspective: A pragmatic Guide to What's Next” released also in May. (But don't tell Webb's Luddites: it shall only enrage them further). I may look closely at this important SkyWorks sanity check down the line, suffice to say that at present it gives no indication of the potential for QC Augmentation of 5G. Instead, let us look to the May edition of Electronics World and the article “Spectrum-Sensing in Cognitive Radio with Matched Filter Detection” by two authors from JECRC University in Jaipur, India. I have to confess that I was ignorant of this particular institution and our two colleagues, Arun Kumar and Nandha Kumar, themselves. I also have to confess that I failed to understand some of the points being advocated until it dawned on me that English was not their native or even first language. Then it also dawned on me that they don't have access to state of the art instrumentation. But what has Matched Filtering to do with Quantum Computers you may ask? Answer: there shall be no need for this particular signal processing detection process. Why? That answer is a heavy duty technical subject matter concerning Mathematical Mappings. But I am raising it now as a placeholder here. So I hope our Indian colleagues take note.

My first quote is usually attributed to the Irishman G. B. Shaw, though it is assured that Friedrich Nietzsche deposited that “One who speaks a foreign language just a little takes more pleasure in it than one who speaks it well. Enjoyment belongs to those who know things halfway.”. Indeed, as native English speakers we take so much for granted. However, is the authors comprehension of were we are at technology wise “halfway”? Perhaps, especially given just how far the UK is behind the US in both the 5G and QC fields. Therefore, let me endeavour, in the spirit of our G7 financiers to begin to “promote a level playing field in international trade” by levelling up the Playing Field just a little for our Indian colleagues.

First, let us begin with the word “Competition”. When the Brits use this word, they really mean “Fair Play”. Whereas the Americans relate instead to Darwinism. I do not intend to go into the preservation of the English language post you-know-what, nor into the nuances of Americanisms, instead I shall merely state that on reviewing these authors additional published technical papers on ResearchGate others also appear to relate to their “ambiguous” use of language. (Nit-picking the “I” in IFFT stands for Inverse not Infinite). Therefore it is their conceptual appreciation which needs to be gauged. By this I am referring to the need to appreciate the distinctions between the Stanford and MIT Schools of Thought in Signal Processing. Indeed, can our Indian colleagues relate to the nuance's even within a common institution like MIT between Alan Oppenheim and Bob Gallagher? However, researchers of the US Berkeley School of Though are usually credited (in the early 2000's) with establishing some of the theoretical fundamental limits of current commercial Spectrum Sensing technology, both under noise and fading conditions. These Indian researchers appear to build on this background. Berkeley researchers were also instrumental in the underpinning of QC Theory.

Clearly, our two colleagues are experts in the application of mathematical modeling, primarily in the field of Statistical Communication Systems. But in their application of the IFFT/FFT all the usual workarounds, zero-padding and windowing etc are called upon. Recall here that it was our old friend, Fred Harris who provided a formal mathematical proof of the equivalence of windowing in the Time Domain to convolution in the Frequency Domain. Why does this matter here?


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