Talk:Fractal antenna/Archive 2

Plagiarism(?) Concerns on Reference 8 (Dec 2019)

Greeting fellow wiki 'editors'. As promised, I am continuing a thorough review of this article's entry. Its going to take a lot of work, in the months ahead. Indeed, I suspect that other 'editors' with first-hand knowledge on the subject will participate at some point. At this time, I am requesting your fellow efforts in taking a look at reference 8, the Lau book. I did a computer search for uniqueness (this is a typical effort undertaken by editors and college professors, for example) and discovered that the Lau section on fractal antennas has an extremely high correlate to the wikipedia entry (this article), and that fractal antenna portions were entered many years ago on wikipedia, before the book was written. IOW wikipedia came first and sections would appear to be 'lifted' from wikipedia. If this is the case then wikipedia is citing a book which tautologically, in part, is in wikipedia. Of course, not all of the Lau description of fractal antennas is from Wikipedia, but the sentences lifted from Wikipedia should be a serious concern.

Plagiarism is a severe act, and before any conclusions are made, it is important to elicidate the evidence, and then make edits to the wikipedia entry accordingly. I am happy to qoute the portions from the book for the comparison, but it is important that this be "verifiable", in this case by other 'editors' who have the reference in-hand.

On the bigger picture, from this point forward, let's keep the fractal antenna article 'real'--by only posting citations we have access to and have REVIEWED --(appropriately shouted:-)

Before I proceed, let's first assume that the case for plagiarism is not proven at this time, and that it would be very helpful for other 'editors' to take their in-hand access to the reference to reach a consensus on this matter. Kindly let me know your access to this reference, and I will present the evidence. I expect to see this matter resolved by the end of December, and thank you for your colleagial assistance. 141.154.68.80 (talk) 21:34, 7 December 2019 (UTC)

Please exercise caution before proceeding with this discussion. The above could be regarded as libellous and Wikipedia treats that very seriously. You should also read this article here. Reusing Wikipedia content is permitted if done properly. Otherwise, you are correct. Circular referencing is always to be avoided, if indeed that is what is happening. --Escape Orbit ^(Talk) 22:00, 7 December 2019 (UTC)

I mean p-l-a-g-i-a-r-i-s-m; not 'fair use of copyright material'. I am using the term legally and correctly. I have no exposure, if that is your concern. And I see no reason why wikipedia would sue the publisher of the book. I will post the evidence on Wednesday, after I have sent it to the publisher's editor (who I know). After the material is posted, the Lau reference needs to be removed from the article.

Again, I want to stress that references (citations)must be in-hand and reviewed by 'editor(s)' before they are posted on the article. Cheers.141.154.68.80 (talk) 23:18, 7 December 2019 (UTC)

In prep for the comparison of book to wikipedia entry, its best to be able to quote out wiki from, say, 10 years ago, to show that the wikipedia entry did not follow the book; the book took from wikipedia. What is the best way to have access to the full wikipedia entry from long ago? Looking for links, procedure, key strokes--tangible means of getting there. Thanks!141.154.68.80 (talk) 20:46, 8 December 2019 (UTC)

My concern is not whether you are using the term correctly, or what your exposure is. My concern is what legal liability you may be exposing Wikipedia to.

I also find your enthusiasm for editors reviewing references puzzling. This concern has not stopped you adding your own original synthesis to the article in response to a cited journal article you have not read. Please remove it. You perhaps misunderstand the purpose of Wikipedia, an encyclopaedia. Encyclopaedias do not review sources. Wikipedia is not interested in any editor's review of what a source says. Editors' responsibility is to gather and reflect what the sources say. No more.

You'll find all previous version of this article on the "View history" tab of the article (not directly from this talk page). Your difficulty will be any part of the content as it stands most likely cannot be dated to any one single date. But is the result of many edits over some while. --Escape Orbit ^(Talk) 15:24, 9 December 2019 (UTC)

Again, you need to read, with care, my comments. They are the comments of an editor, whose task is to VERIFY the validity of a statement(s) so cited. If the statements of the citation are plagiarized, or contain plagiarized material, then they cannot be VERIFIED as --belonging-- to that CITATION. And, 'legal liability' is not, apparently, a term for which you have sufficient knowledge. Here's why: libel refers to statements that are "knowingly false", and made with intent of malice, at least that is the general definition in the United States. My intent is verifying and correcting this wikipedia article, and presenting facts --facts-- that justify that effort. I will not, and have not, made, nor will make, any false statements on this matter. Ergo, they are not 'knowingly false' nor presented with intent of malice against anyone nor anything. Please stop trying to (incorrectly) guess my motives (see above); what I have read; my mood; my sense of 'enthusiasm'; my fears; my acumen; and so on. Keep it factual and colleagial. Have a most pleasant morning.141.154.68.80 (talk) 00:04, 10 December 2019 (UTC)

I had no problem finding the wikiarticle back to, for example, 2005. Perhaps that can be used to show if any phrases , sentences, or paragraphs are the same in the 2019 publication of 'Practical Design of Wireless Products' and without attribution. Unless the citation cites its sources properly then we can't say what the verified proper reference is . We can't verify (origin as belonging to the citation) and if we can't verify we can't cite. This one needs to be removed if that is the case. That's how wiki works. No verification, no citation. The good news is the citation itself cites some references which may be used in place of it to make some points.24.34.111.21 (talk) 18:26, 9 December 2019 (UTC)

I will start there--a 2005 entry. There's at least two or three overwhelming passages that evince plagiarism from the wikipedia entry from (at least) 14 years earlier. Since the origin of these passages does not lie with the citation, any additional statements made in that citation are suspect, unless they themselves cite proper references. I will post these plagiarised passsages on Wednesday, and then remove citation 8 . I believe it can easily be replaced with minor changes to text, and new citations that also convey the intent. 141.154.68.80 (talk) 23:48, 9 December 2019 (UTC)

Lau citation has been removed and replaced with primary references. That section and dispute section expanded for informational content.

Assuming the evidence is shown for plagiarism, there would thus be --two reasons-- not to list the Lau citation: 1) plagiarism creating non-verifiability of origin of statements and 2) primary references replacing a derivative reference (Lau)that itself references the primary references.

The plagiarism should be of interest.24.34.111.21 (talk) 22:10, 10 December 2019 (UTC)

The following are comparisons of the Lau entry (Practical Antenna Design fo Wireless Products, Henry Lau, Artech House, 2019) and samples of far older, prior, WIKIPEDIA entries. The Lau portions are not cited in the book---

PASSAGE 1

Wikipedia 26 dec 2005 A fractal antenna is an antenna that uses a self similar design to maximize the length, or increase the perimeter (on inside sections or the outer structure), of material that can receive or transmit electromagnetic signals within a given total surface area

31 Jan 2010 A fractal antenna is an antenna that uses a fractal, self-similar design to maximize the length, or increase the perimeter (on inside sections or the outer structure), of material that can receive or transmit electromagnetic radiation within a given total surface area or volume

Lau 9.4.1 A fractal antenna is an antenna that uses the fractal geometry to maximize the effective length or increase the perimeter of the material…given a total surface area or volume.

PASSAGE 2

Wikipedia 31 Jan 2010 A fractal antenna…is capable of operating with good-to-excellent performance at many different frequencies simultaneously. Normally standard antennas have to be "cut" for the frequency for which they are to be used—and thus the standard antennas only work well at that frequency.

Lau 9.4.1 In addition, they have good to excellent performance at many different frequencies simultaneously over the traditional antennas. Unless specially treated, traditional antennas are designed for a particular frequency. They will not work well beyond the design frequency…

These comparisons show clear evidence of plagiarism. The Lau entries are both 'lifted' and paraphrased, without attribution, and are found in publicly available material almost 15 years prior to the Lau publication.

The Lau citation should not be used on any fractal antenna entry --unless the material is verified as originating with Lau, or if the material is cited properly in Lau.

As it stands the existing references supersede Lau and are properly cited in the article. 141.154.68.80 (talk) 13:13, 12 December 2019 (UTC)

Log periodic antennas and fractals

Sorry, but the chapter labled "Log periodic antennas and fractals" is not very convincing. Some paranthese may not be placed sensibly, but my main concern is about the logic that ends up calling log periodic antennas to be fractals. Having worked with such antennae and being familiar with their basic principle of operation I must admit that I do not find this convincing and since there is no source for the claim and no explanation I thought I should open a discussion. First of all it should be established if the device is one antenna or an array of separate antennae. We always used to see it as the later while the fractal antenna seems to describe a single and integrated device. The effect might be similar, but if you are prepared to call a physical assembly of multiple antennae tuned to different wavelengths and otherwise similar in design a fractal antenna then why would that logic not apply to the interposed loop antennae on top of radio location vehicles present already in the 1940s ? And surely there have been other such assemblies at that time where a single feeder went out to multiple lines or other geometric designs of different size. But still, going back to my original argument, in my opinion an assembly of separate elements is not the same as the complete integration of the fractal antenna. On the other hand that would of course depend on the definition of such an antenna. Unfortunately the definition given at the top of the page (and on similar pages of Wikipedia in other languages) is in contradiction to an assembly and rather requires the fractal antenna to be a single thing of fractal shape. JB. --92.195.29.107 (talk) 23:27, 26 September 2021 (UTC)

I think we are mostly talking about a single antenna with log periodic elements, but I don't see an essential difference with a log periodic array of separate antennae as far as their fractalness (or otherwise) is concerned. Some authors do indeed regard log periodic antennae as fractal "...every frequency invariant antenna is fractal (self similar). This includes log periodic structures..." [1]. Also [2]. But there does not seem to be general agreement on this; a lot of authors treat them as separate but related [3][4] and others hedge their bets [5]. Perhaps we should be a little less definite about this on the basis of what sources say. One property that can be used to define fractals is that they possess infinite length in a finite volume or area. The length of a log periodic antenna is a geometric progression. With a scaling factor of $\tau <1$ (as it must be if subsequent elements are to decrease in size) the total length of an infinite number of elements is $L/(1-\tau )$ where $L$ is the length of the longest element. This is plainly finite so log periodic antennae do not fit this definition. On the other hand, if one defines fractal simply as infinitely self-similar, then plainly they do so fit. SpinningSpark 16:34, 27 September 2021 (UTC)

Thank you for answering in such detail. Going from the word "fractal" as in fraction or fragment there can be little doubt that the termin refers to self-similarity at different (shrinking) scales. As I learned it the definition was even that it goes down indefinitely. So self-similarity is necessary but not enough to reach fractalness. Otherwise 100 needles of the same type would also fit the description. In my language log periodic antennae are being called logarithmic decadic dipole lines (or arrays) pointing at them being assemblies out of singular dipoles and that can also be seen when you have them in your hands. But I fear that I'll get accused of applying my own brain to things which is forbidden, so forget about all of that. You were so kind to check what can be found in literature. I agree with those sources who do not see fractalness in log periodic antennas but since you found other oppinions I wonder what Wikipedia wants us to do ... just represent all the different oppinions or look up what fractalness means according to the Wikipedia ? I'll leave it at that. Maybe sooner or later somebody else finds a way to solve this in a satisfactory way. JB. --92.195.49.189 (talk) 09:05, 6 October 2021 (UTC)

I've amended the article in line with this discussion. SpinningSpark 10:17, 6 October 2021 (UTC)

I find this discussion surprising, because the whole point of log-periodic antennas IS self-similarity, and I was surprised when I saw a page called "Fractal antennas" because the two concepts are identical. But you won't find that in Wikipedia because there IS NO page on log-periodic antennas (should be!), only on the LPDA which is only one (most commercially important) among a multitude of log-periodic (discrete ratio similarity) or frequency-independent antenna (continuous similarity) designs to which the "fractal" label probably applies (I'm not a mathematician). OF COURSE a true fractal grows to infinitesimal size and to infinite size, so ANY physical antenna has to have a small and large limit beyond which it is no longer fractal; the ratio of those two is the relative frequency range in which the feedpoint impedance and radiation pattern are more or less constant. And in fact a critical design issue for log-periodic antennas is how those limits are dealt with in order to make a finite (and not infinitesimal) transition to something else and still being able to feed it.

If anyone would like to start a page on log-periodic antennas (and rename the current one!) I will help add content. And it may or may not be distinct from "Fractal antennas" which I gather reflects the thinking of a different era. Interferometrist (talk) 20:16, 6 October 2021 (UTC)

This became much more responsive than I ever expected. Thank you all for answering to "my" topic. I should first say that this is not something extremely important to me, so I'll not attempt to start an edit war about it or anything in that direction. I think we can all agree that there is self-similarity in log-periodic antennas. What remains is the question if they are also fractal. I totally agree that "real fractals" in the sense of 3D objects cannot be fractal from infinity to infinity, so in order to apply that property at all we have to accept that limitation. The longer I think about it it comes down to the way one looks at the construction of the log-periodic antennas. To me they prepresent arrays of single dipols where each dipol works on its own and for its own wavelengths and that view is also represented in the term my language (German) uses for them. On the other hand I see now that in English the entire contraption is seen as a single antenna and is called as such. It is hard for me to not call this a stretch, but it's your language and your view, so I have no say in this :-). On the other hand that lowers the bar for something to be called "fractal" ... Maybe we are discussing if orange is rather red or yellow :-) ... I'm somewhat sorry I started this. One thing which led me in that direction is the multiplier by which the smallest element of the log-periodic antenna is smaller than its largest element. In all instances I have ever held in my hands that was something like 1:3 or 1:4 whereas the fractal antennas of the modern 2D design appear to cover much larger multipliers and would accommodate further progression in the same space ... like true fractals which get finer but not larger - where a log-periodic antenna would have to grow. I totally agree that this is not convincing as I have written it here now. I just try to explain my intuition. On the other hand since this is the Wikipedia what I think is totally unimportant. We have to report what the external sources say. And since SpinningSpark invested the time to dig into those we now know that there are different opinions. I was also astonished to find that there is no page for the log-periodic antennas. On the other hand antennas are a somewhat arcane subject for most people :-). Over and out. JB. --92.193.219.120 (talk) 19:45, 7 October 2021 (UTC)

If we are to go down the route that Interferometrist suggests we need some strong evidence concerning current academic consensus on the definition of fractal antenna. Most of the sources I cited are fairly recent, so my reading is that there is no definite consensus on a definition and our article should reflect that. Even Mandelbrot see-sawed on how to define a fractal and never came to a firm position on it. SpinningSpark 19:57, 7 October 2021 (UTC)