The IEEE 802.16 Standard
WiMAX is based aloft IEEE Std 802.16e-2005,18 accustomed in December 2005. It is a supplement to the IEEE Std 802.16-2004,19 and so the absolute accepted is 802.16-2004 as adapted by 802.16e-2005. Thus, these blueprint charge to be advised together.
IEEE 802.16e-2005 improves aloft IEEE 802.16-2004 by:
Adding abutment for advancement (soft and harder handover amid abject stations). This is apparent as one of the a lot of important aspects of 802.16e-2005, and is the actual abject of Adaptable WiMAX.
Scaling of the Fast Fourier transform (FFT) to the approach bandwidth in adjustment to accumulate the carrier agreement affiliated beyond altered approach bandwidths (typically 1.25 MHz, 5 MHz, 10 MHz or 20 MHz). Affiliated carrier agreement after-effects in a college spectrum ability in avant-garde channels, and a bulk abridgement in attenuated channels. Aswell accepted as Scalable OFDMA (SOFDMA). Added bands not multiples of 1.25 MHz are authentic in the standard, but because the accustomed FFT subcarrier numbers are alone 128, 512, 1024 and 2048, added abundance bands will not accept absolutely the aforementioned carrier spacing, which ability not be optimal for implementations. Carrier agreement is 10.94 kHz.
Avant-garde antenna assortment schemes, and amalgam automated repeat-request (HARQ)
Adaptive Antenna Systems (AAS) and MIMO technology
Denser sub-channelization, thereby convalescent calm penetration
Introducing Turbo Coding and Low-Density Parity Check (LDPC)
Introducing downlink sub-channelization, acceptance administrators to barter advantage for accommodation or carnality versa
Adding an added QoS chic for VoIP applications.
SOFDMA (used in 802.16e-2005) and OFDM256 (802.16d) are not accordant appropriately accessories will accept to be replaced if an abettor is to move to the after accepted (e.g., Anchored WiMAX to Adaptable WiMAX).
edit Concrete layer
The aboriginal adaptation of the accepted on which WiMAX is based (IEEE 802.16) authentic a concrete bandage operating in the 10 to 66 GHz range. 802.16a, adapted in 2004 to 802.16-2004, added blueprint for the 2 to 11 GHz range. 802.16-2004 was adapted by 802.16e-2005 in 2005 and uses scalable erect frequency-division assorted admission (SOFDMA) as against to the anchored erect frequency-division multiplexing (OFDM) adaptation with 256 sub-carriers (of which 200 are used) in 802.16d. Added avant-garde versions, including 802.16e, aswell accompany assorted antenna abutment through MIMO (See WiMAX MIMO). This brings abeyant allowances in agreement of coverage, cocky installation, ability consumption, abundance re-use and bandwidth efficiency. WiMax is the a lot of energy-efficient pre-4G address a allotment of LTE and HSPA+.20
edit MEDIA ACCESS CONTROL, MAC (data link) layer
The WiMAX MAC uses a scheduling algorithm for which the subscriber abject needs to attempt alone already for antecedent admission into the network. After arrangement admission is allowed, the subscriber abject is allocated an admission aperture by the abject station. The time aperture can enlarge and contract, but charcoal assigned to the subscriber station, which agency that added subscribers cannot use it. In accession to getting abiding beneath afflict and over-subscription, the scheduling algorithm can aswell be added bandwidth efficient. The scheduling algorithm aswell allows the abject abject to ascendancy Superior of account (QoS) ambit by acclimation the time-slot assignments a allotment of the appliance needs of the subscriber station.
edit Deployment
As a accepted advised to amuse needs of next-generation abstracts networks (4G), WiMAX is acclaimed by its activating admission algorithm accentuation adaptive to the concrete ambiance the RF arresting campaign through. Accentuation is called to be added spectrally able (more $.25 per OFDM/SOFDMA symbol). That is, if the bursts accept a top arresting backbone and a top carrier to babble added arrest arrangement (CINR), they can be added calmly decoded application agenda arresting processing (DSP). In contrast, operating in beneath favorable environments for RF communication, the arrangement automatically accomplish down to a added able-bodied approach (burst profile) which agency beneath $.25 per OFDM/SOFDMA symbol; with the advantage that ability per bit is college and accordingly simpler authentic arresting processing can be performed.
Burst profiles are acclimated changed (algorithmically dynamic) to low arresting attenuation; acceptation throughput amid audience and the abject abject is bent abundantly by distance. Best ambit is accomplished by the use of the a lot of able-bodied admission setting; that is, the contour with the better MAC anatomy allocation accommodation acute added symbols (a beyond allocation of the MAC frame) to be allocated in transmitting a accustomed bulk of abstracts than if the applicant were afterpiece to the abject station.
The client's MAC anatomy and their alone admission profiles are authentic as able-bodied as the specific time allocation. However, even if this is done automatically again the applied deployment should abstain top arrest and multipath environments. The acumen for which is acutely that too abundant arrest causes the arrangement to action ailing and can aswell adulterate the adequacy of the network.
The arrangement is circuitous to arrange as it is all-important to clue not alone the arresting backbone and CINR (as in systems like GSM) but aswell how the accessible frequencies will be dynamically assigned (resulting in activating changes to the accessible bandwidth.) This could advance to chaotic frequencies with apathetic acknowledgment times or absent frames.
As a aftereffect the arrangement has to be initially advised in accord with the abject abject artefact aggregation to accurately activity abundance use, interference, and accepted artefact functionality.
The Asia-Pacific arena has surpassed the North American arena in agreement of 4G broadband wireless subscribers. There were about 1.7 actor pre-WIMAX and WIMAX barter in Asia - 29% of the all-embracing bazaar - compared to 1.4 actor in the USA and Canada.21
edit Affiliation with an IP-based network
The WiMAX Appointment architecture
The WiMAX Appointment has proposed an architectonics that defines how a WiMAX arrangement can be affiliated with an IP based amount network, which is about called by operators that serve as Internet Account Providers (ISP); Nevertheless the WiMAX BS accommodate seamless affiliation capabilities with added types of architectures as with packet switched Adaptable Networks.
The WiMAX appointment angle defines a amount of components, added some of the arrangement (or advertence points) amid these, labeled R1 to R5 and R8:
SS/MS: the Subscriber Station/Mobile Station
ASN: the Admission Account Network22
BS: Abject station, allotment of the ASN
ASN-GW: the ASN Gateway, allotment of the ASN
CSN: the Connectivity Account Network
HA: Home Agent, allotment of the CSN
AAA: Authentication, Authorization and Accounting Server, allotment of the CSN
NAP: a Arrangement Admission Provider
NSP: a Arrangement Account Provider
It is important to agenda that the anatomic architectonics can be advised into assorted accouterments configurations rather than anchored configurations. For example, the architectonics is adjustable abundant to acquiesce remote/mobile stations of capricious calibration and functionality and Abject Stations of capricious admeasurement - e.g. femto, pico, and mini BS as able-bodied as macros.
edit Spectrum allocation
There is no compatible all-around accountant spectrum for WiMAX, about the WiMAX Appointment has appear three accountant spectrum profiles: 2.3 GHz, 2.5 GHz and 3.5 GHz, in an accomplishment to drive standardisation and abatement cost.
In the USA, the better articulation accessible is about 2.5 GHz,23 and is already assigned, primarily to Sprint Nextel and Clearwire. Elsewhere in the world, the most-likely bands acclimated will be the Appointment accustomed ones, with 2.3 GHz apparently getting a lot of important in Asia. Some countries in Asia like India and Indonesia will use a mix of 2.5 GHz, 3.3 GHz and added frequencies. Pakistan's Wateen Telecom uses 3.5 GHz.
Analog TV bands (700 MHz) may become accessible for WiMAX usage, but anticipate the complete cycle out of agenda TV, and there will be added uses appropriate for that spectrum. In the USA the FCC bargain for this spectrum began in January 2008 and, as a result, the better allotment of the spectrum went to Verizon Wireless and the next better to AT&T.24 Both of these companies accept declared their ambition of acknowledging LTE, a technology which competes anon with WiMAX. EU abettor Viviane Reding has appropriate re-allocation of 500–800 MHz spectrum for wireless communication, including WiMAX.25
WiMAX profiles ascertain approach size, TDD/FDD and added all-important attributes in adjustment to accept inter-operating products. The accepted anchored profiles are authentic for both TDD and FDD profiles. At this point, all of the adaptable profiles are TDD only. The anchored profiles accept approach sizes of 3.5 MHz, 5 MHz, 7 MHz and 10 MHz. The adaptable profiles are 5 MHz, 8.75 MHz and 10 MHz. (Note: the 802.16 accepted allows a far added array of channels, but alone the aloft subsets are accurate as WiMAX profiles.)
Since October 2007, the Radio advice Breadth of the International Telecommunication Union (ITU-R) has absitively to cover WiMAX technology in the IMT-2000 set of standards.26 This enables spectrum owners (specifically in the 2.5-2.69 GHz bandage at this stage) to use WiMAX accessories in any country that recognizes the IMT-2000.
edit Ashen efficiency
One of the cogent advantages of avant-garde wireless systems such as WiMAX is ashen efficiency. For example, 802.16-2004 (fixed) has a ashen ability of 3.7 (bit/s)/Hertz, and added 3.5–4G wireless systems action ashen efficiencies that are agnate to aural a few tenths of a percent. The notable advantage of WiMAX comes from accumulation SOFDMA with acute antenna technologies. This multiplies the able ashen ability through assorted reclaim and acute arrangement deployment topologies. The absolute use of abundance breadth alignment simplifies designs application MIMO-AAS compared to CDMA/WCDMA methods, consistent in added able systems.
edit Inherent limitations
WiMAX cannot bear 70 Mbit/s over 50 kilometers (31 mi). Like all wireless technologies, WiMAX can accomplish at college bitrates or over best distances but not both. Operating at the best ambit of 50 km (31 mi) increases bit absurdity amount and appropriately after-effects in a abundant lower bitrate. Conversely, abbreviation the ambit (to beneath 1 km) allows a accessory to accomplish at college bitrates.
A city-wide deployment of WiMAX in Perth, Australia approved that barter at the cell-edge with an calm Customer-premises accessories (CPE) about admission speeds of about 1–4 Mbit/s, with users afterpiece to the corpuscle website accepting speeds of up to 30 Mbit/s.citation needed
Like all wireless systems, accessible bandwidth is aggregate amid users in a accustomed radio sector, so achievement could adulterate in the case of abounding alive users in a individual sector. However, with able accommodation planning and the use of WiMAX's Superior of Service, a minimum affirmed throughput for anniversary subscriber can be put in place. In practice, a lot of users will accept a ambit of 4-8 Mbit/s casework and added radio cards will be added to the abject abject to admission the amount of users that may be served as required.
edit Silicon implementations
Picture of a WiMAX MIMO board
A amount of specialized companies produced baseband ICs and chip RFICs for WiMAX Subscriber Stations in the 2.3, 2.5 and 3.5 GHz bands (refer to 'Spectrum allocation' above). These companies include, but are not bound to, Beceem, Sequans, and PicoChip.
edit Comparison
Comparisons and abashing amid WiMAX and Wi-Fi are common because both are accompanying to wireless connectivity and Internet access.27
WiMAX is a continued ambit system, accoutrement abounding kilometres, that uses accountant or actionable spectrum to bear affiliation to a network, in a lot of cases the Internet.
Wi-Fi uses actionable spectrum to accommodate admission to a bounded network.
Wi-Fi is added accepted in end user devices.
Wi-Fi runs on the Media Admission Control's CSMA/CA protocol, which is connectionless and altercation based, admitting WiMAX runs a connection-oriented MAC.
WiMAX and Wi-Fi accept absolutely altered superior of account (QoS) mechanisms:
WiMAX uses a QoS apparatus based on admission amid the abject abject and the user device. Anniversary affiliation is based on specific scheduling algorithms.
Wi-Fi uses altercation admission - all subscriber stations that ambition to canyon abstracts through a wireless admission point (AP) are aggressive for the AP's absorption on a accidental arrest basis. This can could cause subscriber stations abroad from the AP to be again disconnected by afterpiece stations, abundantly abbreviation their throughput.
Both 802.11 (which includes Wi-Fi) and 802.16 (which includes WiMAX) ascertain Peer-to-Peer (P2P) and ad hoc networks, breadth an end user communicates to users or servers on addition Bounded Breadth Arrangement (LAN) application its admission point or abject station. However, 802.11 supports aswell absolute ad hoc or associate to associate networking amid end user accessories after an admission point while 802.16 end user accessories have to be in ambit of the abject station.
Although Wi-Fi and WiMAX are advised for altered situations, they are complementary. WiMAX arrangement operators about accommodate a WiMAX Subscriber Unit which connects to the city WiMAX arrangement and provides Wi-Fi aural the home or business for bounded accessories (e.g., Laptops, Wi-Fi Handsets, smartphones) for connectivity. This enables the user to abode the WiMAX Subscriber Unit in the best accession breadth (such as a window), and still be able to use the WiMAX arrangement from any abode aural their residence.
WiMAX is based aloft IEEE Std 802.16e-2005,18 accustomed in December 2005. It is a supplement to the IEEE Std 802.16-2004,19 and so the absolute accepted is 802.16-2004 as adapted by 802.16e-2005. Thus, these blueprint charge to be advised together.
IEEE 802.16e-2005 improves aloft IEEE 802.16-2004 by:
Adding abutment for advancement (soft and harder handover amid abject stations). This is apparent as one of the a lot of important aspects of 802.16e-2005, and is the actual abject of Adaptable WiMAX.
Scaling of the Fast Fourier transform (FFT) to the approach bandwidth in adjustment to accumulate the carrier agreement affiliated beyond altered approach bandwidths (typically 1.25 MHz, 5 MHz, 10 MHz or 20 MHz). Affiliated carrier agreement after-effects in a college spectrum ability in avant-garde channels, and a bulk abridgement in attenuated channels. Aswell accepted as Scalable OFDMA (SOFDMA). Added bands not multiples of 1.25 MHz are authentic in the standard, but because the accustomed FFT subcarrier numbers are alone 128, 512, 1024 and 2048, added abundance bands will not accept absolutely the aforementioned carrier spacing, which ability not be optimal for implementations. Carrier agreement is 10.94 kHz.
Avant-garde antenna assortment schemes, and amalgam automated repeat-request (HARQ)
Adaptive Antenna Systems (AAS) and MIMO technology
Denser sub-channelization, thereby convalescent calm penetration
Introducing Turbo Coding and Low-Density Parity Check (LDPC)
Introducing downlink sub-channelization, acceptance administrators to barter advantage for accommodation or carnality versa
Adding an added QoS chic for VoIP applications.
SOFDMA (used in 802.16e-2005) and OFDM256 (802.16d) are not accordant appropriately accessories will accept to be replaced if an abettor is to move to the after accepted (e.g., Anchored WiMAX to Adaptable WiMAX).
edit Concrete layer
The aboriginal adaptation of the accepted on which WiMAX is based (IEEE 802.16) authentic a concrete bandage operating in the 10 to 66 GHz range. 802.16a, adapted in 2004 to 802.16-2004, added blueprint for the 2 to 11 GHz range. 802.16-2004 was adapted by 802.16e-2005 in 2005 and uses scalable erect frequency-division assorted admission (SOFDMA) as against to the anchored erect frequency-division multiplexing (OFDM) adaptation with 256 sub-carriers (of which 200 are used) in 802.16d. Added avant-garde versions, including 802.16e, aswell accompany assorted antenna abutment through MIMO (See WiMAX MIMO). This brings abeyant allowances in agreement of coverage, cocky installation, ability consumption, abundance re-use and bandwidth efficiency. WiMax is the a lot of energy-efficient pre-4G address a allotment of LTE and HSPA+.20
edit MEDIA ACCESS CONTROL, MAC (data link) layer
The WiMAX MAC uses a scheduling algorithm for which the subscriber abject needs to attempt alone already for antecedent admission into the network. After arrangement admission is allowed, the subscriber abject is allocated an admission aperture by the abject station. The time aperture can enlarge and contract, but charcoal assigned to the subscriber station, which agency that added subscribers cannot use it. In accession to getting abiding beneath afflict and over-subscription, the scheduling algorithm can aswell be added bandwidth efficient. The scheduling algorithm aswell allows the abject abject to ascendancy Superior of account (QoS) ambit by acclimation the time-slot assignments a allotment of the appliance needs of the subscriber station.
edit Deployment
As a accepted advised to amuse needs of next-generation abstracts networks (4G), WiMAX is acclaimed by its activating admission algorithm accentuation adaptive to the concrete ambiance the RF arresting campaign through. Accentuation is called to be added spectrally able (more $.25 per OFDM/SOFDMA symbol). That is, if the bursts accept a top arresting backbone and a top carrier to babble added arrest arrangement (CINR), they can be added calmly decoded application agenda arresting processing (DSP). In contrast, operating in beneath favorable environments for RF communication, the arrangement automatically accomplish down to a added able-bodied approach (burst profile) which agency beneath $.25 per OFDM/SOFDMA symbol; with the advantage that ability per bit is college and accordingly simpler authentic arresting processing can be performed.
Burst profiles are acclimated changed (algorithmically dynamic) to low arresting attenuation; acceptation throughput amid audience and the abject abject is bent abundantly by distance. Best ambit is accomplished by the use of the a lot of able-bodied admission setting; that is, the contour with the better MAC anatomy allocation accommodation acute added symbols (a beyond allocation of the MAC frame) to be allocated in transmitting a accustomed bulk of abstracts than if the applicant were afterpiece to the abject station.
The client's MAC anatomy and their alone admission profiles are authentic as able-bodied as the specific time allocation. However, even if this is done automatically again the applied deployment should abstain top arrest and multipath environments. The acumen for which is acutely that too abundant arrest causes the arrangement to action ailing and can aswell adulterate the adequacy of the network.
The arrangement is circuitous to arrange as it is all-important to clue not alone the arresting backbone and CINR (as in systems like GSM) but aswell how the accessible frequencies will be dynamically assigned (resulting in activating changes to the accessible bandwidth.) This could advance to chaotic frequencies with apathetic acknowledgment times or absent frames.
As a aftereffect the arrangement has to be initially advised in accord with the abject abject artefact aggregation to accurately activity abundance use, interference, and accepted artefact functionality.
The Asia-Pacific arena has surpassed the North American arena in agreement of 4G broadband wireless subscribers. There were about 1.7 actor pre-WIMAX and WIMAX barter in Asia - 29% of the all-embracing bazaar - compared to 1.4 actor in the USA and Canada.21
edit Affiliation with an IP-based network
The WiMAX Appointment architecture
The WiMAX Appointment has proposed an architectonics that defines how a WiMAX arrangement can be affiliated with an IP based amount network, which is about called by operators that serve as Internet Account Providers (ISP); Nevertheless the WiMAX BS accommodate seamless affiliation capabilities with added types of architectures as with packet switched Adaptable Networks.
The WiMAX appointment angle defines a amount of components, added some of the arrangement (or advertence points) amid these, labeled R1 to R5 and R8:
SS/MS: the Subscriber Station/Mobile Station
ASN: the Admission Account Network22
BS: Abject station, allotment of the ASN
ASN-GW: the ASN Gateway, allotment of the ASN
CSN: the Connectivity Account Network
HA: Home Agent, allotment of the CSN
AAA: Authentication, Authorization and Accounting Server, allotment of the CSN
NAP: a Arrangement Admission Provider
NSP: a Arrangement Account Provider
It is important to agenda that the anatomic architectonics can be advised into assorted accouterments configurations rather than anchored configurations. For example, the architectonics is adjustable abundant to acquiesce remote/mobile stations of capricious calibration and functionality and Abject Stations of capricious admeasurement - e.g. femto, pico, and mini BS as able-bodied as macros.
edit Spectrum allocation
There is no compatible all-around accountant spectrum for WiMAX, about the WiMAX Appointment has appear three accountant spectrum profiles: 2.3 GHz, 2.5 GHz and 3.5 GHz, in an accomplishment to drive standardisation and abatement cost.
In the USA, the better articulation accessible is about 2.5 GHz,23 and is already assigned, primarily to Sprint Nextel and Clearwire. Elsewhere in the world, the most-likely bands acclimated will be the Appointment accustomed ones, with 2.3 GHz apparently getting a lot of important in Asia. Some countries in Asia like India and Indonesia will use a mix of 2.5 GHz, 3.3 GHz and added frequencies. Pakistan's Wateen Telecom uses 3.5 GHz.
Analog TV bands (700 MHz) may become accessible for WiMAX usage, but anticipate the complete cycle out of agenda TV, and there will be added uses appropriate for that spectrum. In the USA the FCC bargain for this spectrum began in January 2008 and, as a result, the better allotment of the spectrum went to Verizon Wireless and the next better to AT&T.24 Both of these companies accept declared their ambition of acknowledging LTE, a technology which competes anon with WiMAX. EU abettor Viviane Reding has appropriate re-allocation of 500–800 MHz spectrum for wireless communication, including WiMAX.25
WiMAX profiles ascertain approach size, TDD/FDD and added all-important attributes in adjustment to accept inter-operating products. The accepted anchored profiles are authentic for both TDD and FDD profiles. At this point, all of the adaptable profiles are TDD only. The anchored profiles accept approach sizes of 3.5 MHz, 5 MHz, 7 MHz and 10 MHz. The adaptable profiles are 5 MHz, 8.75 MHz and 10 MHz. (Note: the 802.16 accepted allows a far added array of channels, but alone the aloft subsets are accurate as WiMAX profiles.)
Since October 2007, the Radio advice Breadth of the International Telecommunication Union (ITU-R) has absitively to cover WiMAX technology in the IMT-2000 set of standards.26 This enables spectrum owners (specifically in the 2.5-2.69 GHz bandage at this stage) to use WiMAX accessories in any country that recognizes the IMT-2000.
edit Ashen efficiency
One of the cogent advantages of avant-garde wireless systems such as WiMAX is ashen efficiency. For example, 802.16-2004 (fixed) has a ashen ability of 3.7 (bit/s)/Hertz, and added 3.5–4G wireless systems action ashen efficiencies that are agnate to aural a few tenths of a percent. The notable advantage of WiMAX comes from accumulation SOFDMA with acute antenna technologies. This multiplies the able ashen ability through assorted reclaim and acute arrangement deployment topologies. The absolute use of abundance breadth alignment simplifies designs application MIMO-AAS compared to CDMA/WCDMA methods, consistent in added able systems.
edit Inherent limitations
WiMAX cannot bear 70 Mbit/s over 50 kilometers (31 mi). Like all wireless technologies, WiMAX can accomplish at college bitrates or over best distances but not both. Operating at the best ambit of 50 km (31 mi) increases bit absurdity amount and appropriately after-effects in a abundant lower bitrate. Conversely, abbreviation the ambit (to beneath 1 km) allows a accessory to accomplish at college bitrates.
A city-wide deployment of WiMAX in Perth, Australia approved that barter at the cell-edge with an calm Customer-premises accessories (CPE) about admission speeds of about 1–4 Mbit/s, with users afterpiece to the corpuscle website accepting speeds of up to 30 Mbit/s.citation needed
Like all wireless systems, accessible bandwidth is aggregate amid users in a accustomed radio sector, so achievement could adulterate in the case of abounding alive users in a individual sector. However, with able accommodation planning and the use of WiMAX's Superior of Service, a minimum affirmed throughput for anniversary subscriber can be put in place. In practice, a lot of users will accept a ambit of 4-8 Mbit/s casework and added radio cards will be added to the abject abject to admission the amount of users that may be served as required.
edit Silicon implementations
Picture of a WiMAX MIMO board
A amount of specialized companies produced baseband ICs and chip RFICs for WiMAX Subscriber Stations in the 2.3, 2.5 and 3.5 GHz bands (refer to 'Spectrum allocation' above). These companies include, but are not bound to, Beceem, Sequans, and PicoChip.
edit Comparison
Comparisons and abashing amid WiMAX and Wi-Fi are common because both are accompanying to wireless connectivity and Internet access.27
WiMAX is a continued ambit system, accoutrement abounding kilometres, that uses accountant or actionable spectrum to bear affiliation to a network, in a lot of cases the Internet.
Wi-Fi uses actionable spectrum to accommodate admission to a bounded network.
Wi-Fi is added accepted in end user devices.
Wi-Fi runs on the Media Admission Control's CSMA/CA protocol, which is connectionless and altercation based, admitting WiMAX runs a connection-oriented MAC.
WiMAX and Wi-Fi accept absolutely altered superior of account (QoS) mechanisms:
WiMAX uses a QoS apparatus based on admission amid the abject abject and the user device. Anniversary affiliation is based on specific scheduling algorithms.
Wi-Fi uses altercation admission - all subscriber stations that ambition to canyon abstracts through a wireless admission point (AP) are aggressive for the AP's absorption on a accidental arrest basis. This can could cause subscriber stations abroad from the AP to be again disconnected by afterpiece stations, abundantly abbreviation their throughput.
Both 802.11 (which includes Wi-Fi) and 802.16 (which includes WiMAX) ascertain Peer-to-Peer (P2P) and ad hoc networks, breadth an end user communicates to users or servers on addition Bounded Breadth Arrangement (LAN) application its admission point or abject station. However, 802.11 supports aswell absolute ad hoc or associate to associate networking amid end user accessories after an admission point while 802.16 end user accessories have to be in ambit of the abject station.
Although Wi-Fi and WiMAX are advised for altered situations, they are complementary. WiMAX arrangement operators about accommodate a WiMAX Subscriber Unit which connects to the city WiMAX arrangement and provides Wi-Fi aural the home or business for bounded accessories (e.g., Laptops, Wi-Fi Handsets, smartphones) for connectivity. This enables the user to abode the WiMAX Subscriber Unit in the best accession breadth (such as a window), and still be able to use the WiMAX arrangement from any abode aural their residence.
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