Talk:WiMAX
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[edit] Future use
I note there is a list of current networks using WiMAX.
This press release (18th nov. 2006) describes an planned system which will exemplify a situation where LOS-WiMAX is the "best" solution; lack of (and the risks of installing and maintaining) a copper infrastructure good enough for DSL; high cost of satellite networks... One to keep an eye on for when they finally implement it. Emyr42 22:42, 26 November 2006 (UTC)
“IRAQTEL selects Redline to establish Iraq’s first WiMAX network” http://www.redlinecommunications.com/news/pressreleases/2006/111806.html (Accessed 26/11/2006)
[edit] statement not true
"Another application under consideration is gaming. Sony and Microsoft are closely considering the addition of WiMAX as a feature in their next generation game console. This will allow gamers to create ad hoc networks with other players."
This statement is blatantly wrong, unless we're talking about the next next generation of consoles, which would make this pure speculation and inappropriate for the article. Kevin143 07:15, 14 January 2006 (UTC)
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iPhone's signifcance:
WiMAX, WiFi, LTE are a progression to 'AIP, all IP, wireless networks. Connection to PSTN and packet based networks are provided for but WiMAX and WiFi in particular can be installed as AIP only in greenfield networks. Connection to PSTN and other networks in that case is handled as an external gateway or device rather than an integral aspect of the network. There will be legacy PSTN networks around For decades.
What is most significant about Apple's iPhone is not what network it runs on but it's stress on software that is used in PC/networking environment. In this case OS X v 10.5 code named Leopard. And it uses AJAX which has grown in popularity among web and mobile web and media content developers.
This is a major shift in emphasis. I wrote a blog/article on the subject: http://www.maravedis-bwa.com/article-6.html
The reason why this is significant is that open applications and can be run and connected to content on AIP networks just as they can on the Internet. Apple's advertisements tout that 'this is the real Internet' and not the 'mobile Internet'. That is not entirely true at this point: Apple has developed on an 'open platform' but they have not yet provided 3rd parties with APIs to enable aps on the iPhone. Jobs says iPhone is now open to AJAX developers but we shall have to see. Regardless, the shift is occurring to AIP and open development environments.
Many developers for cell phones will claim that their development environment is open: uses Java and open development platforms. OK, to a certain extent that is true. But where that breaks down completely is how it is applied: cell phone service on phones is offered in walled gardens controlled by the operator. The user gets a limited choice of services. Operators are pressured to offer the best content and popular applications but users are castrated by operators in their ability to choose open applications beyond that.
This business methods shift is more important and will impact more people's careers and pocket books than changes in wireless link technology. It is disruptive: creative destruction.
[edit] too vague -- rephrase!
The article uses at least three abbreviations, OFDMA, PHY and DRM without explaining what they mean. The article also uses abbreviations like these several paragraphs before explaining their meaning.
- I've added links for OFDM(A) and PHY, and deleted the DRM section. I used to sell Moto WiMAX gear and I've never heard of it. Please sign your contributions in the talk section by clicking the "signature" icon in the editing toolbar.--Phil Holmes (talk) 13:32, 9 December 2007 (UTC)
The following sentence in the "Technical advantages" section is far too vague and needs to be rephrased:
"What is important for business using this technology is to ensure that it is managed correctly"
Well, of course, but surely this can be said for any business using any technology. What do you mean by being managed correctly? restricted access? ... encryption? ... bandwidth? ... agreements with other businesses? And why is this so important? I would like to rephrase this sentence myself but I have trouble understanding what it is trying to say in the first place, so I'll leave it for the time being.
- Clearwire cited the security of OFDM as a huge selling point. I called them to ask about it. They could not explain it, of course.90.135.114.78 (talk) 22:04, 18 May 2008 (UTC)
[edit] Small countries
I live in Bahrain, and it small island country (665 km²).
Is it possible to cover all Bahrain area using WiMAX with ability to provide 100 000 users with internet services at 1Mbit/s. how many antennas will be needed and can GSM antennas be used.
And should we wait for Global Area Network (GAN(IEEE 802.20)) . so we get always-connected devices. --Zayani 21:49, 2 December 2005 (UTC)
[edit] Specs?
Specs? -- Toytoy 17:04, Aug 20, 2004 (UTC)
- What specs, as mentioned in the article, it covers up to 50 KM and at 11GHz.--Jondel 09:49, 14 Oct 2004 (UTC)
[edit] 802.20
The (slowly) evolving 802.20 spec has never been refered to as "compatible" with WiMax. They will likely be incompatible---
Don't agree. It depends on what you mean by compatible, I guess. Let's use the term bridgeable or routable -- and end system attached to a .20 network can communicate with one attached to a .16 network. The technical key is the Logical Link Control which was standardized years ago by the IEEE 802.2 committee. All IEEE 802 networks use the same LLC which means that they can all be bridged together and they can all fit into a routed network.
No, 802.20 has shifted several times but has been generally controlled by Flarion, (now Qualcomm). the standard has been based on FH-OFDM but has since been adjusted to add in more flexibility. So instead of being specialized as a mobile cellular system, it has changed stripes to become more generalized so it can be used also for high bandwidth VPN and other applications as well. But because these use different modulation schemes, even though they are both forms of OFDM they are not air-link compatible.
But even if you wish to broaden the term, there might be more good news ... if you want it. Currently the PAR for 802.20 says that the committee will deliver specs for both MAC and PHY. As the 802.16 standard continues to mature, it is incorporating just about everything that one might want in the .20 MAC. (the d spec, when ratified, becomes the 802.16-2000 standard; the e spec is busy incorporating mesh/mobility features). So it's possible (speculation at this date, of course) that the .20 committee will simply opt to create a different PHY spec and reuse the .16 MAC.
Compatibility has practical concerns: being compatible at a higher level such as link control and IP/SIP is being pursued by every major aspect of wired and wireless networking. But in practical terms this still can leave end users with incompatible devices because the the air-link is not compatible. Even within a standard such as 802.16e-2005 rigorous designs have to be implemented and tested for conformance and compatibility before it can be assured. There is now talk about whether common system profiles for similar spectrum and usage requirements can be 'harmonized' between 802.16e-2005 WiMAX and upcoming 3GLTE/HSOPA cellular. Even though these will use similar basic sets of technology the chances are that harmonization will not happen - at least not soon.
Without end user device compatibility handsets, laptops and other devices must use multiple or multi-mode SoC chipsets and hand-of between one system and another becomes more difficult or drags on. This adds significantly to cost, power consumption and size.
The IEEE 802.22 Cognitive Radio RAN group has shifted toward adoption of 802.16e-2005 OFDMA and MAC as the core or starting point. One reason for doing so is to take advantage of WiMAX chips, development platforms and growing pool of design talent.
802.20 is also shifting to use a broader range of FEC, HARQ, and MIMO technologies.. making it look a lot more like 802.16-2005. The reason? Obviously to broaden out it's applications from a mobile to a 'wireless Ethernet' capability able to serve multiple needs. Of course, that leads to the question of what the purpose is for 802.20 in the first place? To simply provide an industry leader their on playing field?
802.20 support appears to have waned: they have open positions and low attendance at plenary sessions. Little momentum is evident among major operators who will wait to see if WiMAX gains momentum and ITU and other regulatory groups formally accept WiMAX into the family for IMT-2000 and IMT-Advanced. Or they will wait for LTE to develop: Ericsson says a specification will be ready by the end of 2007, others think that is way too early - more like late 2008 for the standard to develop and 2010-2012 for commercial systems to be certified for deployment... major new wireless systems need consensus to build among multiple vendors. I think 802.20 is all but dead.. but they said that about IDen several years ago.
The 802.20 effort appears all but dead: it exists only as a formality and for supporters to develop some common technology. Qualcomm will likely make WiMAX chips as well as for LTE even though the company is being put at odds with over IPR pursuits within those efforts. Qualcomm has the best vision, imo, for evolution of the wireless industry towards a multi-spectrum, multi-mode and multi-service environment. Q has excellent design skills and is further along the path of combining diverse frequency spectrum and applications: MediaFlo video with 3G cellular. This use of low frequency spectrum for multi cast (or Rural Area Network, RAN) service where range and penetration are most essential with higher frequency service where high density of users and higher bandwidth service is required, is an early prescription for an essential taking element that will evolve into 4G.
WiMAX and LTE will both evolve to use multiple spectrums for multiple services on a best use basis. These are also going to become "smart wireless broadband networks".
==> Robert Syputa, Maravedis, WiMAX Pro, LLC
[edit] link ranges
The 50 km (30 miles) number actually came from the functional requirement document that IEEE 802.16 wrote before embarking on the creation of this standard. It actually relates to microwave links with very heavily directive antennas. At microwave frequencies, there isn't any point to go with lowly directional antennas, because there is no gain from multipath propagation. Systems in the millimeter bands (2-11 GHz) will have lower directional antenna gain to be able to have some gain from multi path components. Typical link-distances (on paper) will be 3-4 km in suburban environments. For mobile systems, where the handset has virtually no gain, the link budgets are mathematically similar to those of CDMA, with practical link-distances (using 3G channel models) of around 350 meters.
A similar story holds for the throughput number of 70 Mbps that is often thrown around. Analysis show that for the mobile component, throughput rates of the PHY are only larger than those of the high-end 3G specs for very short ranges (less than 50 meters). Since the MAC was originally written for very high throughput systems where some efficiency could be easily sacrificed for simplicity and structure, it is questionable whether the throughput above the MAC will be competitive with 3G, let alone substantially better.
People who hence expect (per the Intel hype) to be able to run 70 Mbps at 50 km distance with a handset are hence going to be slightly disappointed. Commercially you should expect end users to get symmetrical speeds of up to 10Mbps access if in line of site at over 8Km. If in a NLOS environment the distances will be around 2Km and the speeds may be lower especially on the uplink.
[edit] Understandability
Should have more links in the article to other articles... Examples: amortization? ASIC?
[edit] Intro paragraph
Could someone please rewrite the opening paragraph in plain English? The information about "IEEE 802.16" and "working group number 16 of IEEE 802" tells me nothing about what WIMAX actually is. How about something like "WIMAX is a technology standard for delivering broadband Internet over wide areas" (I'm not sure if that's actually what it is.) The cryptic IEEE stuff should be pushed down (way down) into the article. --Lee Hunter 20:22, 12 September 2005 (UTC)
[edit] WiMAX in New Orleans
Here’s an interesting link [1]. Someone may want to put it in the article. -- Thorpe talk10:31, 13 September 2005 (UTC)
[edit] WiMAX in Estonia
15. sept 2005 - near Tallinn, Estonia a WiMAX area was launched with range ~30km. Provided by Norby Telecom [2] (web page in Estonian or Russian).
[edit] Second Para - Reference to WiFi
It's unclear to me why the article starts out its description of WiMAX with what appears to be an obscure reference to WiFi:
"Wi-Fi also extends to all flavors of wired ethernet..."
- Tony Close
[edit] This article needs reworking
It contains patches of incoherent jibberish and misinformation and is generally poorly structured. There are several problem in addition to the ones mentioned above. Question is, who's brave enough to take it on?
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- That's because you have Engineering people writing these articles. For the most part, their language only speaks to one another, not the average layman.
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- It looks like to me like marketing people wrote most of this.90.135.114.78 (talk) 22:06, 18 May 2008 (UTC)
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[edit] real world tests
From the Register's article; Behzed Nadji, AT&T's Chief Architect [said] range of 3 to 5 miles and 2 Mbit/s then one site rarely saw throughput rise above 500 kbit/s.
Does anybody have access to the actual test report? It wasn't linked from the article unfortunately. Mozzerati 10:18, 30 October 2005 (UTC)
[edit] ClearWire?
Anyone know how ClearWire (website) fits into this? I met a ClearWire rep once, and he said it wasn't officially "WiMAX," but a similar technology. Several sites seem to indicate that they either use a pre-WiMAX implementation or that they really are using WiMAX.
Their top-teir plan is only 1.5mbps, though, so that doesn't really fit into the 70mbps potential of true WiMAX, I guess. Just wondering. They offer service in my city, so I've been intrigued. I just signed up for ACS's EV-DO implementation and am satisfied, although not blown away.
If ClearWire really is WiMAX, should they be mentioned in this article? cluth 02:38, 12 March 2006 (UTC)
ClearWire is NOT WiMAX, see http://www.nextnetwireless.com/products.asp it's a CDMA variant. No, Clearwire uses NetNet/Motorola Expedience 256 FFT TDD OFDM technology that is a propietary precursor. It is not WiMAX. TF, ClearWire must convert to WiMAXm when it is available (wave 2 802.16e-2005 which is the migration path to 802.16m/j and LTE inter-networking)
- Robert Syputa - I made a change in the future technology section and removed commercial link in external links - fair is fair. —Preceding unsigned comment added by 67.183.20.8 (talk) 04:40, 24 January 2008 (UTC)
To my knowledge ClearWire uses the Wimax Technology in Denmark, but not in the Wimax frequency range, therefore I have added it together with Butler Networks, who uses Alvarion-based Wimax equipment, also in another spectrum.
[edit] Removing irrelevant links
I've just removed numerous links to manufacturers of devices and test equipment, since they provide no insight into the technology. Moreover, Wikipedia is not a link farm or web directory. If anybody disagrees with this, please let me know your reasons. Mindmatrix 21:43, 3 April 2006 (UTC)
[edit] Corrected a typo
Changed specrutm to spectrum
Amit 203.187.132.68 07:24, 8 June 2006 (UTC)
[edit] WirelessMAN
Although WiMAX seems to be becoming the more common term, I find it odd that nowhere does this article mention that 802.16 is officially called WirelessMAN (see http://www.ieee802.org/16/).
[edit] Simplification
As a reader, it seems to information needs an improved structure of organization. It should start with creating more and better titles and subtitles for someone who needs specific information. Examples are "The Spectrum" "Hurdles" "Advantages" "Pros/Cons" "Use In Today's World" "Coverage" "Competing Technologies" "Goals or Achievements" "Specifications" and many others. Some are duplicates but I think a better structure of headings and a more plentiful amount of them would help me find out what I need to know quickly. Very sepecific and technical terms are used, therefore, references after the word is used on the page would make it helpful. The text, as I stress, should be much better organized and simplified for my understanding.
[edit] Rewrite
I've given this a fairly substantial re-write. I've tried to get rid of some of the contentious stuff, given it a slightly better flow, and got rid of the product announcements, since these seemed to be getting out of hand. I think it's better now, but YMMV. --Phil Holmes 16:37, 9 August 2006 (UTC)
[edit] WiMAX is not a technology
The intro para includes a lengthy statement that starts with "'WiMAX is not a technology". It isn't? Correct me if I'm wrong, but in order to work with a WiMAX system you need to be using a radio, in certain frequencies, with certain power requirements, with certain protocols, with certain signaling requirements. Can someone explain how this is not a technology? Maury 14:22, 25 September 2006 (UTC)
- It's something of a fine point. Strictly, the technology is all defined in 802.16E. The WiMAX forum defines how that technology is to be employed, and tests for compliance. My personal view? I can't be too excited about that fine a definition, and I think 99% of the population would see both WiMAX and WiFi as technologies. --Phil Holmes 14:31, 25 September 2006 (UTC)
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- It's a problem though because right before the quote saying WiMax isn't a technology, there's a quote that says, "WiMax is a technology...". Uh, yeah, we gotta pick. 68.202.66.211 06:13, 9 December 2006 (UTC)
I find it somewhat amusing that the 802.16 article contains basically no technical detail, which is instead covered here. Perhaps a merge is in order? Is putting the tech section for 802.16 here really that "wrong", considering we all think the terms are synonymous anyway? Maury 22:32, 26 September 2006 (UTC)
All Wikipedia summaries of technology terms (Ethernet, VoIP, etc.) refer to the collection of standards and protocols that make up the "technology". Technology terms, by definition, always refer to the collection of protocols or specifications that make up the technology. The statement by the OECD is unnecessary and confusing to most people looking for information on WiMax. Coreyem 16:13, 11 October 2006 (UTC)
WiMAX is not a 'technology' because all modern cellular systems have evolved into wireless platforms which incorporate several technologies, many of which are common or similar between systems. In addition, the platforms are designed, as much as can be foreseen and is practical, to be 'evolutionary' rather than task specific and fixed. The field of wireless has been enabled through increasingly software defined and diverse types of base stations and user devices. The software programmability can allow upgrade and, in some cases, multi-mode capabilities using the same core functions. The carriers want 'evolution rather than revolution' with each advance in system design. That has already been seen in current 3G systems but still not to the extent that carriers would like. No system is likely to be designed that won't eventually have to be hardware upgraded. But the fewer years there are between 'fork lift' upgrades, the more operators can recoup capex and return a profit. Operators also want to focus less or less often on hardware and more on software and services. That is why 802.16 has core requirements that are adaptable to many types of applications and ability to extend the platform in several ways, such as higher order MIMO-AAS, without breaking core compatibility. Like LTE, WiMAX strives to be a 'long term evolution' framework platform. So both because these systems use a set of core and optional technologies and because they are fully expected to evolve over time, it is misleading to call WiMAX or LTE 'a technology'.
[edit] spectrum used
the article says that
"The original WiMAX standard (IEEE 802.16) specified WiMAX in the 10 to 66 GHz range. 802.16a, updated in 2004 to 802.16-2004 (also known as 802.16d), added support for the 2 to 11 GHz range."
WiMAX has been extended and will be considered for use in sub 1 GHz including 700 MHz and 'white spaces' spectrum. A primary reason it wasn't specified for sub 2Ghz has been that little spectrum was available. That will change with new auctions of 700 MHz next year. Robert, Maravedis
I understand that therefore WiMax can use the 2 to 66 GHz range. Later the article says that
"Wi-Fi is a Wireless Local Area Network (LAN) technology that works in unlicensed spectrum, using the 2.4GHz and 5 GHz bands. Wi-Fi is a cheap and easy way of providing local connectivity at high speed. WiMAX uses licensed spectrum and has strong authentication mechanisms built in."
If Wi-Fi operates in the 2.4 and 5 GHz bands and WiMax can use the 2 to 66GHz range, then there is an overlap. WiMAx has even been deployed in London in the 5.8 lightly licensed spectrum.
Theoretically, WiMAX can operate in any of the spectrum you point to (2 to 66 GHz). However, there are practical restrictions on that. In licensed spectrum, the use of that spectrum has to be licensed for that purpose, and just because the IEEE designed a system to be able to use some spectrum, doesn't mean that it's licensed to do so. It can definitely be used in the same spectrum as WiFi, since this is unlicensed and (AFAIK) there are no restrictions of which applications can use that spectrum. However, there are restrictions in terms of power, etc., which make unlicensed spectrum less attractive. As a result, most 802.16e deployments are expected to be in licensed bands, in particular 3.5 GHz, 2.5 GHz and 2.3 GHz. HTH. --Phil Holmes 12:45, 29 October 2006 (UTC)
Theoretically WiMAX can also be used under 2GHz. There is a working group in 802.16 and the WiMAX Forum has a 'sub 1GHz' study group. 700 MHz has drawn the attention of some vendors. The problem with WiMAX being adopted to 700 MHz is that it must gather the support of multiple vendors in order to make the cut as a new 'system profile'. The WiMAX Forum has been concentrating on spectrum already widely available and on standards policies efforts, such as with ITU for inclusion into IMT-2000 and IMT-Advanced. There have been efforts for opening up sub 1 GHz spectrum as well. But this has yet to rise to being specified as a new system profile. In some respects, I think that 'Qualcomm play chess, WiMAX plays checkers'.. meaning that Qualcomm may be the first to extend their efforts into the very desirable sub-1G spectrum while WiMAX Forum has their thumbs stuck up their... oops, better not say that!
The new age of wireless or 4G will be 'multi-spectrum, multi-mode and multi-service'. Think about it: where would you want to put multi-cast/unicast type service? Obviously in lower frequency spectrum (Duh). Where would you want to have very high bandwidth networks? in higher frequency spectrum because you have to have small coverage areas in order to back-haul all the users. The logical thing that Qualcomm has figured out but WiMAX seems woefully lacking of group-grope intelligence, is to design systems to use spectrum more optimally based on frequency. Not saying that any prescription would be globally available, but the advantages are so dramatic that the effort is justified.
Robert Syputa
[edit] UMTS/HSOPA/LTE
I cleaned up the HSOPA thing (the author named the section for the committee that's developing UMTS, and there were a lot of confusing switches in terminology that were probably wrong. Also it suggested HSOPA (which, apparently, is what it was referring to) was a done deal, whereas it's actually a proposal before the LTE (which deals with a lot more than just air interface standards...)
At the risk of sounding hypocritical given I added the UMTS-TDD part, it strikes me that there's way too much information in that whole area. The UMTS section should really, in this context, encompass UMTS, UMTS-TDD, and UMTS over HSOPA, and should probably be about a third as long. This article is primarily about WiMAX, not WiMAX's competitors. It shouldn't be split into two independent parts as it is now. I'll not do it yet, because I fear I may have offended the original author who I saw put a lot of work into it last night and I've already made a huge number of changes; I'd be interested in feedback though and maybe I'll work on it next week. Squiggleslash 17:46, 17 November 2006 (UTC)
Absolutely agree Dilane 03:02, 19 November 2006 (UTC)
Ok. I just rewrote the entire "Competing standards" area. I tried to ensure all the core points made under each heading were included, and moved the bulk of the information to the attached template. I hope I haven't offended anyone, as I've removed a lot of stuff that I know a lot of people worked on, but I honestly don't think the competition section should have been anything like as long and specific as it was. Squiggleslash 14:34, 27 November 2006 (UTC)
The section comparing WiMAX and 3G technologies erroneously describes LTE and ultra mobile broadband as being evolutions of 3G. They are hardly more evolutions of cellular than WiMAX: both are new air-link technologies that have absolutely no compatibility to use the same spectrum as existing networks. What's more, WiMAX was just accepted as a member of the IMT-2000 family: WiMAX is a cellular multi-service system (that includes mobile).
Robert Syputa, WiMAX Pro, LLC
[edit] clean up
Reduced number of primary sections. Created uses. Got rid of some wording to stay in 32K.
Need to be done: - as mentioned somewhere, the intro is baffling. - need a good uses section: nobody knows how to fill the usages of wimax? Dilane 03:02, 19 November 2006 (UTC)
I deleted mention of C-Band satellite spectrum. This is an interesting detail but is not a determinant for WiMAX, LTE, #G, IMO-2000 or IMT-Advanced as it is just a part of the regulatory environment the competitive developments deal with. Other developments, such as long term potential to use agile/cognitive radio technology for white spaces and, possibly extending across several other spectrums over the next 10-20 years.
Spectrum is entering a new era in which multi-frequency use of spectra on a purpose-use basis will evolve. That is because all of the wireless systems are converging on similar control and networking layers that are highly adaptive and integrated with computer and network virtualization and data structures. This changes the relationship of spectrum and wireless interfaces. —Preceding unsigned comment added by 67.183.19.101 (talk) 05:20, 3 May 2008 (UTC)
[edit] Spectral Efficiency
I've reverted a section added by Lesswire, where he claimed EV-DO rev B was more spectrally efficient than WiMAX, and added a table showing .16e with .45 bit/s/Hz and rev B with 1.05 bit/s/Hz. All the information I've seen shows WiMAX with a maximum efficiency of 5 bit/s/Hz, so Lesswire underestimates it by a factor of over 10. I'd be interested in other views on the claims. --Phil Holmes 11:42, 27 December 2006 (UTC)
I'm inclined to agree with you, also because it's not really relevent there except as part of a wider discussion comparing the standards (the sentence pops up with little context and no discussion of other technical characteristics of the technologies.) I know Lesswire considers it a very important issue, and I would encourage him to work on a Spectral efficiency of mobile Internet standards article but be mindful that simply adding claims to related articles needs to be done with care and consideration of context. Squiggleslash 13:58, 27 December 2006 (UTC)
What's relly needed here is some references. I found this [3] which suggests that WiMax beats the mobile phone standards. See page 8. darkov 14:04, 27 December 2006 (UTC)
Also see here [4] which suggests about 3.1-3.8, but it's from 2005 and may be referencing an older draft of the standard. Darkov 14:09, 27 December 2006 (UTC)
The spectral efficiency of WiMAX/802.16 OFDMA, 802.20, and LTE which proposes to use OFDMA on the down-link and SC-OFDM on the up-link are all similarly heading close to the practical limits for spectral efficiency defined by Shannon's theorem. The majority of advances in effective spectral efficiency and network throughput are occurring in the 'spatial' domain: in the areas of MIMO, AAS beam forming and MIMO-AAS which can adaptively combine the techniques. MIMO takes advantage of multi-path to effective reuse spectrum and enhance signals for higher reliability, sustainability and range. AAS uses beam forming/steering which also is a method to reuse spectrum within a cell or sector. And MIMO-AAS can combine the methods to use one or both depending on the deployment scenario and channel conditions. These can then be used with 'smart wireless broadband network' methods and topologies to reuse spectrum on a localized or tiered spatial domain. That is a fancy way of describing capabilities such as mobile multi-hop relay, MMR, in 802.16j. MMR can be used to hop to remote stations as repeaters, in-building networks, and blocked coverage areas. WiFi MESH is a similar concept: but instead of using entirely different spectrum with course granularity, channel and system management capability, 802.16/WiMAX can use channel sub-sets of the frequency band in a more managed system designed not to cause interference.
The effect of starting with high core air-link spectral efficiency, building granularly and with MIMO/MIMO-AAS so that signal strengths are enhanced, thus allowing higher order modulation (to 64 QAM), and reusing the spectrum up to several times over, multiples the effective spectral and network efficiency.
A basic driver is the move to higher bandwidth per user which requires more back-haul, which, in turn, necessitates building networks more densely. That has driven 3G cellular networks to deploy more densely as well. As long as that is the trend, then design of the system to be 'smart wireless BB networks' that take their advantage increasingly in the spatial domain becomes by far the most cost effective and efficient way to go. Robert Syputa, Maravedis, Feb, 2007 - Bringing this full circle to the discussion of link spectral efficiencies, network operators have measured average link efficiencies of early deployed WiMAX systems: they come in 2.8 b/hz. This compares favorably with similar real-world deployments of HSDPA cellular which reportedly come in at 2.2 b/hz. Both are far off the theoretical efficiencies as one would expect. And neither shows a particularly case for adoption when taken by itself. But when combined with MIMO-AAS and granular network topologies that allow spectrum reuse within and between cells, the theoretical limits are multiplied... and system designs made more complicated. That has pushed development of channel measurement and estimation, quasi-orthogonality, and numerous other methods to reduce co-channel and other interference, 'smart network' allocation of sub-bands/sub-channels etc. In turn, this is a major reason for NOT combining WiMAX and 802.16 into one section: WiMAX and LTE will use multiple developments including cognitive radio being developed within 802.22 and other efforts and evolution of 'smart wireless broadband networks' that include MESH and ad-hoc networks.
[edit] Simplification again of competition section
I've resimplified the competition area again. Before adding more information, please consider the following:
- Is it relevent? (Discussions concerning the future of OFDM really do not belong there)
- Is it in the right place? (UMB is a development of CDMA2000, it should have been added to the Cellular 3G/4G section)
- Are you adding too much information? (In my view, I'm already doing that, and want to simplify the section further. There's no reason why we should have huge competition sections.)
There is a work-in-progress Comparison of wireless data standards section that may be more appropriate for much of the information I know you might be itching to add to the competition section.
I'd be grateful for advice on how to simplify the section further. If we can halve the size, removing as much redundant or inappropriate material as possible, I think that'd be a good thing. I might add I don't like the 4G section, I just added it because it looks like people didn't "get" the 3G & 4G section. Squiggleslash 04:36, 7 January 2007 (UTC)
[edit] Linkspam
I'm assuming most spammers aren't reading the articles they spam, so I've added a spamtrap, in terms of a comment that starts at the last legitimate link and ends below a "sample" "spam" (no it doesn't link to anything)
A comment is a <!-- tag, that prevents rendering of anything that follows until the next -->
I noticed someone removed my attempt to do this earlier (with a real spam) without explanation, so I assume the concept was confusing. If that isn't the case, and the remover just didn't want to explain, then I'd welcome comments on feedback.
Note though: If you want to add legitimate links, insert them before the <!-- tag.
Hopefully this will reduce the effectiveness of the spammers a little, and in the long term reduce the amount of spam. --Squiggleslash 17:20, 2 February 2007 (UTC)
- The contributor most guilty of this seems to be 24.17.253.75. Is it worth getting this IP address blocked? --Phil Holmes 08:16, 19 October 2007 (UTC)
[edit] Casino
Why are there references to the casino in the "Future of IEEE 802.16" section —The preceding unsigned comment was added by Enstine86 (talk • contribs) 23:54, 6 February 2007 (UTC).
- It was vandalism. It's now been corrected. --Phil Holmes 16:59, 9 February 2007 (UTC)
[edit] Zune Phone!
The zune phone is gonna use this to send songs to each other! It sounds so good amybe someone can mention it?
- If you can find a reliable site which says it was going to be able to, feel free; I does seem to go against Microsoft's DRM tactics though. Emyr42 10:41, 12 February 2007 (UTC)
[edit] Merge with 802.16?
I certainly support this. Commercial and technological aspects of this do not belong to two different categories. Porttikivi 09:40, 14 February 2007 (UTC)
- What about IEEE 802.11 and Wi-Fi? Do you think they should be merged? (I don't - I see the purpose of separating the IEEE standard from other issues in both cases.) Guy Harris 23:27, 26 February 2007 (UTC)
No, WiMAX is not just 802.16. WiMAX is primarily 802.16 but it can and does embrace parts of several other standards including in areas of IMS, seamless roaming, system hardware such as bus interface and form factors, and smart antenna systems that are not fully defined in the 802.16 standard. 802.16d/e/j/m provides the framework but can adapt other technologies as 'well. For example, 802.22, RAN cognitive radio, has adapted the 802.16 core PHY and MAC. As far as I know the air-link will not be compatible per se, but since it is designed to use the same ICs and development tools as WiMAX, it will readily allow development of multi-mode chip sets and devices. WiMAX is also, like 3G LTE, being evolved toward 4G. The 802.16e-2005 standard has been proposed for inclusion into IMT-2000 and the future version, 802.16m (WiMAX II), will be proposed for IMT-Advanced. Therefore, tying WiMAX to 802.16 is like tying 3G to a single standard while it more appropriately addresses multiple and evolving standards.
- Robert Syputa,—The preceding [[Wikipedia:Signatures] comment was added by 24.18.175.33 (talk • contribs) 21:20, 14 February 2007 (UTC).
WiMAX can also refer to the WiMAX forum which is (like WiFi) responsible to popularize this technology. IEEE 802.16 only specifies the lower layers of the wireless technology, whereas WiMAX adds further specifications to make the entire thing work. WiMAX is mroe of a marketing term, whereas 802.16 is a technical term. Xwas 22:55, 26 February 2007 (UTC)
[edit] WiMAX vs Wifi section
Apologies to Dkondo as I just massacred your changes from last night, but I felt that the additions had three or four major problems:
- Too much speculation and hype. The changes made predictions about the future of WiMAX in terms of its affect on the market, which is unencyclopedic and lacks neutrality.
- Too much redundancy. There are only so many ways you can say that WiMAX costs a lot to implement, or that it has greater range and is intended for use in metropolitan area networks.
- Not necessarily relevant. Comparing WiMAX and Wifi is a little like comparing Bluetooth and Wifi, or USB and Ethernet (or even better GSM and DECT.) The systems are not intended to solve the same problems even if sometimes they overlap, and so talking about ones success being at the expense of the other, which the tone of the changes implied, strikes me as missing the point.
- Too much emphasis on a side issue. The article is primarily about WiMAX. I spent a while a few months ago cleaning up a section that compared WiMAX to every cellular standard under the Sun. I reduced it to about a third of its size, and it's still too big in my eyes. I know others here agreed with me on that. As it is, I still think the updated WiMAX vs Wifi section is too big, it probably could be reduced to three or four sentences (bulleted or otherwise.)
I hope this explains why I made the changes I did, and I hope you understand why and have some agreement. I'm not trying to upset anyone, it's just it's very easy for an article on a particular subject to end up side tracked, and this seems especially the case with anything on telecommunications these days, where articles often spend more time saying what something is not than what it actually is.
Best, --Squiggleslash 12:57, 19 March 2007 (UTC)
[edit] "Comparisons with WiFi" section innaccurate
This section is simply incorrect and/or biased. The implication is made that WiFi 802.11 only works inside a building. The current statement "This represents the real extent of its ability to provide commercial or mobile Internet services. It is not easy to use Wifi to provide Internet access outside of the "provider's" own property." is just plain wrong, since wireless mesh products are being used to provide Internet connectivity to dozens or hundreds of square miles of mamy cities around the US and the world. Revised the page for NPOV re: Wi-FI and added information on the related and complementary technology of wireless mesh. 71.6.14.105 22:08, 27 March 2007 (UTC)
Wireless mesh networks only join different networks. They're not a way for someone to extend the range of their own network into the properties of others far away, without those others being actively involved. So I don't really see the problem with the wording.
Realistically, you can only reliably use 802.11 to provide network access to property you own (or have direct permission to mount an AP upon)
There's no implication that 802.11 only works inside a building, and I'm not sure why you would be reading that into what is written. --Squiggleslash 02:31, 28 March 2007 (UTC)
Perhaps I am making that inference because of these words: "[Wi-Fi] is frequently used to provide Internet access to third parties within a single room or building". It is apparent that there is some reason you do not wish to have an accurate description of the use of Wi-Fi outoors, such as a reference to wireless mesh networking, in this article. WiMAX has precisely the same limitations as Wi-Fi as a practical matter, in that one must own towers or have permission to use existing towers to set up the network.
Your statement above "Wireless mesh networks may only join different networks" is hard to understand, but whatever it means, is proved false by the dozens of metropolitan wireless mesh networks in operation today across the US and around the world using Wi-Fi and wireless mesh networking.
Bottom line, I won't waste my time getting in a revise/revert duel with you. I attempted WP:Assume_good_faith, but it's not working in this case -- as is so often my experience on Wikipedia.71.6.14.105 22:45, 29 March 2007 (UTC)
The assumption that WiMAX networks must use owned/leased towers is partly correct. WiMAX is more like cellular wireless in that it is prescribed for licensed spectrum, it is a managed network, and it is designed to cover wide areas. But WiMAX also is architecturally designed as a 4G network as defined ITU: it is highly scalable from fempto scale base stations that use low power and have limited range similar to a WiFi access point. But WiMAX is being designed to have several levels of management and self configuration capability built into the various scales of base stations.
A basic difference between WiFi and WiMAX and 3G cellular networks stems from their use of licensed spectrum: WiFi is user adopted and can be 'virally deployed'. WiFi can have managed network capabilities but most deployments are ad hoc user deployments with 'planning' being done in a gross manner and adjusted in the field. WiFi MESH that have been deployed thus far are not part of 802.11 standards. 802.11s may have an impact to standardize WiFi MESH but that remains to be seen. Right now, it remains a no-mans land of incompatibility. The vision of MESH networks in which users take part in the mesh is not feasible for contention based networks such as 802.11. WiFi must either redefine the MAC considerably or forget about ever doing viral MESH networking... people close to this have already conceded.
However, the contention that WiMAX cannot be deployed by users or must use towers for deployment is just dead wrong. While wide area coverage will typically require the use of 'macro' cellular base stations deployed on towers, prominent geographic features and buildings, WiMAX can also be deployed as intra-building, campus-wide, tiered VPNs and specialty purposed networks by independent companies and users. This all depends on the service providers. Some have already initiated programs to sell services to business, government and education organizations that are deployed and owned by the user. The service providers maintains control of the spectrum.
WiMAX is being adopted to the semi-unlicensed 3.65-3.70 GHz spectrum in the U.S. and some systems are available for 5 GHz unlicensed. The 3.65 systems will use a different MAC which meets FCC requirements for shared access. liaison groups within 802.11 & 802.16 are working on interference/co-habitation between systems: WiMAX will be used to some degree in unlicensed spectra but, of course, still must obey rules for power and interference.
The key point is that vendors have developed ICs, RFICs, antennas and other components that that are common between the various system profiles. The system and device vendors still must develop that into systems that provide seamless handover but there are no road blocks.
Robert Syputa, WiMAX Pro, LLC
Housekeeping: I added a short paragraph in this section and don't know if my identity was automatically recorded... Robert Syputa
- It wasn't. If you use the 4 twiddle method of signature (or click the signature icon on the toolbar above the edit window) then your username and the date are automatically added. This makes tracking changes much easier for other users. --Phil Holmes 08:58, 3 August 2007 (UTC)
- quoting "However, the contention that WiMAX cannot be deployed by users or must use towers for deployment is just dead wrong" , you mean that is possible a point-to-point (Ad-Hoc mode) between two wi-max dongle , for example? 88.149.167.45 15:12, 12 October 2007 (UTC)
[edit] Intro Change
I have added the following line to the intro as it was too techy before: "The standard aims to provide wireless data in a similar fashion to WiFi but on a larger scale and speed , hence making national wireless networks possible." If you think it should be paraphrased please do , but I think its link with wifi should be done right from the beginning —The preceding unsigned comment was added by 82.35.33.103 (talk) 01:59, 4 April 2007 (UTC).
[edit] Removed repeated section
The section "Broadband access" followed by "limitations" was repeated in the article.
[edit] Current developments section
I removed the part:
"On May 1, 2007, FCC Approves First WIMAX-class Laptop Card. [1]"
because this approval was for the NextNet/Motorola Expedience OFDM 256-FFT TDD card. This will never be upgraded to WiMAX-16e or WiMAXm. Clearwire will deploy WiMAX mobile staring at the end of 2007 but must decide whether to replace or deploy side-by-side with their existing NN Expedient networks. I talked with their head of strategic development this last Wednesday at WiMAX World in Vienna.
Robert Syputa, Maravedis, WiMAX Pro, LLC.
[edit] OFDM system comparison table
Feel free to add WiMAX/802.16 columns to the OFDM#OFDM system comparison table. Mange01 12:16, 17 July 2007 (UTC)
[edit] Legal Issues
I currently own a WiMAX device that boasts the connection radius of 30 miles. I have verified this by going to my friends house, and using my laptop to connect to the device. But I have stopped using it because, I want to know, Is this legal? Can I broadcast such a network? Do I have to obtain a license or such to gain the ability to legally broadcast such a signal?
[edit] WiMAX is not 4G
The way we call 3G then 4G just fashional. The main feature of generation to generation is Compatibility. So does WiMAX compatible with 3G? Can we use WiMAX with NodeB?
3G is used coding technique to carry data, while WiMAX is pure IP already, just step down to carry voice. They are difference world.
By conclusion, we cannot say WiMAX is 4G, the idea of Generation happen when we are going to 3G, then 0G, 1G and 2G are defined.Sypaseuth 08:12, 23 July 2007 (UTC)
WiMAX is just as compatible with 3G as LTE is likely to be or it needs to be. Compatibility is being achieved at several different interface and system management levels but neither WiMAX, UMB, LTE or other future OFDM systems will be compatible with 3G wireless air interfaces. You or I don't decide what these terms mean; we look to industry groups such as NGMN group and ITU to set standards and goals that end up being adopted to mean the next and next generation of wireless. WiMAX is pursuing IMT-Advanced and NGMN is devising guidelines for devising 4G and has just as legitimate a right to be called 4G as any other wireless system. Sprint, calls WiMAX 4G already. I think it's more appropriate to say WiMAX is on the path to becoming 4G by ITU definitions of IMT-Advanced.
Robert Syputa
Note: I made changes to the spectrum section. The statement <One of the significant advantages of WiMAX is spectral efficiency. For example, 802.16-2004 (fixed) has a spectral efficiency of 3.7 bit/s/hertz, as compared to similar technologies that often are less than 1 bit/s/hertz efficient such as WiFi.> is misleading Qualcomm, for example, claims nearly eh same spectral efficiency for EVDO rev A as for WiMAX.
[edit] Australia
No mention of Australia's WiMAX project
- Check http://en.wikipedia.org/wiki/List_of_Deployed_WiMAX_networks and I think you'll find it there. --Phil Holmes 10:57, 4 August 2007 (UTC)
[edit] WiMAX as a service?
Would calling WiMAX a "service" help to clear up the ambiguity between WiFi and WiMAX? WiFi is most definitely not a service, at least not one provided by a retailer. It sounds like WiMAX will be operating much more like a telephone. <spetz>.71.187.179.213 18:08, 27 August 2007 (UTC)
[edit] WiMAX Architecture
A WiMAX architecture section was recently added.
<clip>I added this to the section: It's important to note that the functional architecture can be designed into various hardware configurations rather than fixed configurations. For example, the architecture is flexible to allow various scale and functionality of remote/mobile stations and collaborative aggregations of femto, pico, and mini RS/MS.</clip>
Architecture is becoming increasingly important for 3G, LTE and WiMAX as more services are being delivered over wireless broadband. IMS is another example of the attempt to organize approaches to building a multi-service environment. The 'WiMAX architecture' is not burdened directly by the need to fit into incumbent networks and is, therefore, able to be devised more as from a clean sheet of paper.
Divining a long term strategy for systems architecture is not an easy task: 1) Difficulty in determining all types and impacts of services likely to influence system design needs. 2) Making the architecture flexible, highly scalable, and still quantifiable to that systems can be tested and certified to specific system profiles and compatibility requirements with the goal of providing an open systems architecture is difficult. This has proven to be a tough goal for IMS - several vendors have said that IMS has not achieved early penetration and compatibility between vendors is still uncertain. Defining of systems architecture while many applications are rapidly being developed for wireless environments is overall a difficult task. There is pressure to define architectures so that vendors can move on in development of systems but also pressure to allow significant flexibility that allows for rapid advances and evolution of smart distributed network topologies.
-Robert Syputa, Sr. Partner/Analyst, Maravedis —Preceding unsigned comment added by 67.183.23.74 (talk) 16:41, 22 October 2007 (UTC)
[edit] New one in Sderot
http://www.govtech.com/dc/articles/147054
worth mentioning. —Preceding unsigned comment added by 99.250.93.87 (talk) 07:19, 31 December 2007 (UTC)
[edit] Latency
If anyone have some latency info please add to the article.. —Preceding unsigned comment added by 79.138.199.114 (talk) 19:27, 22 April 2008 (UTC)
