Talk:Radio spectrum/Archive 1

Archive 1

Other systems

In subsection Named frequency bands only the frequency allocation for system M has been given. There are also some other systems. For example, in the international system (B,G) each channel has a cahnnel band of 7 Mhz with an additional guard band of 1 MHz in UHF. So the band limits are different. These should also be shown. Nedim Ardoğa (talk) 14:22, 17 November 2009 (UTC)

Dubious

According to the article:

"In theory, any portion of the electro-magnetic spectrum may be used for information-carrying, so that there is no upper or lower limit to the frequencies of radio transmission."

The first part of this looks perfectly reasonable, but beyond a certain point it wouldn't be called radio transmission, would it? For example, infrared and visible light used for communications would never be called "radio"? I haven't changed this because I'm not 100% sure. 86.134.30.149 (talk) 11:59, 19 November 2009 (UTC)

I don't see why visible light shouldn't be considered electro-magnetic radiation, after all the visible light that existed just after the big bang has been stretched due to the expansion of the universe to become what is now called the microwave background radiation. I suppose it's a matter of an arbitrary human definition what is considered radio and what isn't. — Preceding unsigned comment added by 12.94.93.158 (talk) 23:33, 11 October 2018 (UTC)

The above comment is correct, and the article should be changed. There is absolutely a upper limit to the frequency of radio waves. The definition of that point may be different for different entities (it may be a different cutoff for astronomers than in communications, for example), but there is a cutoff, as stated above. —Preceding unsigned comment added by 129.65.197.87 (talk) 22:37, 29 November 2009 (UTC)

Interesting. It seems likely that there would be an upper limit, but what causes it? Just because we typically change the name from radio to light at a certain frequency, it doesn't mean the mechanism changes - it's all just EM waves right? Now if somebody has a mechanism for a frequency limit, that would be good to include... GyroMagician (talk) 09:41, 20 January 2010 (UTC)

There are no theoretical limits to the frequency of electromagnetic waves that can be used to carry information. (At extremely high or low frequencies there would be practical problems.) However, there are frequency limits on what would be called "radio" waves. Therefore, the part of the statement that's relevant to this article seems false, and the part that is true seems irrelevant. I've deleted it. 86.136.194.230 (talk) 03:49, 27 January 2010 (UTC)

You could put a Morse key in line with an X-ray tube and blast out dits and dahs somewhere in the 10 kEV end of the electromagnetic spectrum, but no-one is going to call that "radio". Working DX would be a problem; propagation characteristics are poor even with a sunspot maximum. --Wtshymanski (talk) 04:04, 27 January 2010 (UTC)

"Light" and "radio waves" are manifestations of the phenomenon and are technically interchangable. In the Terehertz domain, both terms are used. I regard the above statement as true, although I see it might be a bit confusing. —Preceding unsigned comment added by 192.35.35.35 (talk • contribs)

From a practical point of view, radio frequencies are bounded by the limits of the radio window. Of course, defining RF in this way only has meaning for terrestial communications. SpinningSpark 18:17, 10 July 2010 (UTC)

"bounded by the limits of the radio window" - if that excludes the long-wave radio-communication then it cannot be the only limitation... — Preceding unsigned comment added by 129.242.158.79 (talk) 09:36, 25 June 2020 (UTC)

Query

The article notes that:

"The SHF and EHF bands are sometimes not considered to be a part of the radio spectrum, forming their own microwave spectrum."

However, it does not at this point mention the terahertz band, which is also listed in the preceding table, and presumably needs the same (or similar) caveat. —Preceding unsigned comment added by 86.134.30.149 (talk) 12:27, 19 November 2009 (UTC)

ITU Band 0

Is there really such an animal? Or has this been arrived at by extension from the ITU defined bands? If so it is OR and should be removed. SpinningSpark 18:19, 10 July 2010 (UTC)

band designation

not sure your sources (possibly old textbooks?), but in radio frequencies "G-band" is commonly used by the communication and remote sensing communities to indicate the frequency range from (about) 145 to (about) 220 GHz, It corresponds to the usable range of a WR5 waveguide. see for example Urteaga et al., 2002, in: IEEE 24th Annual Technical Digest of gallium Arsenide IC Symposium, 44 (http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1049026) 192.45.72.26 (talk) 16:58, 5 November 2010 (UTC)GD192.45.72.26 (talk) 16:58, 5 November 2010 (UTC)

ITU Bands

I'm unclear about the origin of the stated "ITU Bands" 1 to 3. The ITU Radio Regulations (latest version, Edition of 2008) does not identify bands below Band 4 (VLF, 3 to 30 kHz).

Since bands 1 to 3 are clearly not defined in the Radio Regulations it seems to me wrong to present them as "ITU Bands" and I propose that bands 1 to 3 be deleted from the table so that it aligns with the Radio Regulations. --MarkPos_{(User Page | Talk | Contribs)} 13:24, 13 September 2011 (UTC)

I do not have a full copy of the ITU Radio Regulations; however, it may be plausible they were defined in an earlier edition then dropped from later editions. The ITU does not regulate frequencies below 9 kHz (which is within VLF), so it may have later been decided to reduce the text of the regulations by removing the definitions of frequency ranges they do not regulate. If they were never defined by the ITU, at some point in time, I find it rather curious they would start numbering the ranges with "4". I do not doubt that the terms ELF, SLF, and ULF exist though. –Sparkgap (talk) 19:57, 13 September 2011 (UTC)

On a related note, does the 2008 ed, have a definition for 12, THF (300 to 3000 GHz)? This is a relatively new term, and I've not seen text from a standards or regulatory body which defines it. –Sparkgap (talk) 20:03, 13 September 2011 (UTC)

Thanks for the thoughts. I do have a full copy of the 2008 ed of the RR, which is my point of reference for the above comment. Article 2 clearly states that the RF spectrum is "subdivided into 9 frequency bands" and then shows them as bands 4 to 12 in a table. The numbering starts with 4 because the band number is mathematically related to the frequency of the range. Band 12 (300 to 3000 GHz) does not have a symbol in the table equivalent to the VHF, EHF, etc. definitions for other bands. On this basis I think that the "ITU Bands" table in the article should certainly be edited to align with the current version of the Radio Regulations in force and I'll make the changes tomorrow, unless there is strong objection from anyone. --MarkPos_{(User Page | Talk | Contribs)} 09:09, 14 September 2011 (UTC)

I did not make the association previously with the band numbers and the Powers of 10, but now it makes sense as to why they would start with 4. (And perhaps I should have read the comment before the table, rather than focusing on the table.) Anyway, as long as the changes are limited to the "Table of ITU Radio Bands", I will support this change. –Sparkgap (talk) 19:56, 14 September 2011 (UTC)

Done. I also took the opportunity to correct the reference to the latest edition of the RRs and also to flag that the final 2 columns of this table are not part of the Radio Regs. Actually I think that the final 2 columns of the ITU table probably ought to be deleted, because the table purports to be the ITU table but actually contains information that is not taken from the ITU table. --MarkPos_{(User Page | Talk | Contribs)} 13:04, 15 September 2011 (UTC)

I removed the last column "Typical sources", as it appeared to be a redundant re-listing of what was in the first. I see no issue with leaving "Wavelength Range" for informative purposes, as long as it is marked in some manor that it is addition information, as it is currently. –Sparkgap (talk) 16:00, 15 September 2011 (UTC)

IEEE US Bands

I'm a bit worried about this table too. The list of bands is correctly taken from IEEE Std 521-2002, but the citation is against the "Origin of name" column, not the title. My copy of IEEE Std 521-2002 certainly does not contain anything about the origin of the names, so readers could be mistaken into thinking that the "origins" are taken from the standard, when they are not. I think that some additional citation needs to be given for these origins, otherwise they should be removed from the table (they could perhaps be moved to a new section, instead). It probably also ought to be clarified that IEEE Std 521-2002 is specifically for radar band nomenclature, not a general nomenclature for all RF bands. Any thoughts? --MarkPos_{(User Page | Talk | Contribs)} 13:11, 15 September 2011 (UTC)

If the cite is on a column heading, for a column that does not contain any material in the stated reference, then that cite should either be moved or removed. As for the specific column in question, it is interesting, but it needs citations. Also, the table may or may not be the best location for name origins; I am unsure.

While the standard was intended for radar band nomenclature, I believe all the band letters started out as such, and they were later adopted for other (non-radar) microwave uses. I think it would be appropriate to mention their original intent somewhere, but in practice, the nomenclature in that table is not just used for radar. Many times, I've heard and read the term L band used to refer to communication uses in the frequency range 1 to 2 GHz. –Sparkgap (talk) 16:37, 15 September 2011 (UTC)

Thanks. I've tidied it up a bit, but probably still room for improvement. --MarkPos_{(User Page | Talk | Contribs)} 08:12, 16 September 2011 (UTC)

I moved the cite out of the section name. Section names should only contain text, or things will break. I believe a wiki policy or guideline covers this issue, but I couldn't find it quickly. I'm short on time at the moment. –Sparkgap (talk) 20:12, 16 September 2011 (UTC)

New technologies

I think this article (and other articles related to radiowaves) should include current technologies such as cellphones, wifi and wimax and their radio frequency so the user has an idea where they are allocated in the spectrum. Thanks --Camilo Sanchez (talk) 16:49, 28 April 2012 (UTC)

Cell phone bands

There doesn't seem to be any info on cell phone bands in this article, other than they use UHF.--Wyn.junior (talk) 02:03, 11 April 2014 (UTC)

There's a link to Cellular frequencies - probably listing all those in this article would be too much detail for an overview. --Wtshymanski (talk) 18:52, 11 April 2014 (UTC)

That link addition was my edit. There should be a summary.--Wyn.junior (talk) 03:27, 12 April 2014 (UTC)