Showing posts with label WiMAX. Show all posts
Showing posts with label WiMAX. Show all posts

WiMAX technology

WiMAX is similar to Wi-Fi technology. both create hot-spots. Wi-Fi can cover several hundred meters while WiMAX covers a range of 40-50 km. It provides a wireless alternative to cable, DSL, and also have broadband access.

WiMAX can be used as a complementary technology to connect 802.11 hotspots to the internet. Mobile-Fi is the mobile version of WiMAX. It is used to provide internet access to mobile users at data rates even higher than available in today broadband links.

A wireless broadband solution that offers various features of WiMAX with a lot of flexibility in terms of potential service offering is WiMAX.


A Mobile-Fi user can enjoy broadband internet access even while traveling in a moving car or train. WiMAX could potentially be deployed in a variety of spectrum bands like in different range 2.3 GHz, 2.5 GHz, 3.5 GHz, and 5.8 GHz.

A WiMAX architecture consists of two major parts: Main part is to be (i) A WiMAX base station (ii) A WiMAX receiver.

Following Major principles :

  • Spectrum is − able to be deployed in both licensed and unlicensed spectra.
  • Topology − supports different Radio Access Network topology.
  • IP connectivity network − supports a mix of IPv4 and IPv6 network interconnects in application and clients servers.
  • Mobility management − It is a possibility to extend the fixed access to broadband multimedia services delivery.
  • Interworking − WiMAX support independent RAN architecture to enable seamless integration and interworking with 3GPP2, 3GPP, and  WiFi networks.
A wireless broadband solution that offers various features with a lot of flexibility in terms of potential service offering is WiMAX.
  • WiMAX support multipath.
  • WiMAX must be provided up to 50 km of service area range.
  • WiMAX uses OFDM technology.
  • WiMAX support TDD and FDD.
  • WiMAX offer modulation and error correction.
  • Adaptive modulation enables a WiMAX system to optimize the throughput based on the when propagation conditions apply.
  • Very scalable bandwidth and high-speed data rate.
  • WiMAX benefits are that it is flexible and dynamic per-user resource allocation.
  • Support for advanced antenna techniques.
  • Support for mobility.
  • Portable internet usage.
  • Quality of service support.
  • It is IP based architecture.
  • WiMAX is always best connected.
  • The most important application of WiMAX technology offered by  is business, Multiplayer interactive gaming, backhaul, consumer connectivity, large area coverage access
WiMAX standard :

These standards were issued by IEEE 802.16 into the subgroup of 802.16a / REV d / e standard that originally covered the Wireless local loop (WLL) technologies with radio spectrum from 10 to 66 GHz. Recently were extended below 10 GHz.

In the year of January 2003, the approved IEEE 802.16a as an amendment to IEEE  802.16 defining as a line of sight capability (LOC).


In the year of 2004, the IEEE 802.16 Revd was introduced to support indoor customer premises equipment through additional radio capabilities like antenna beamforming and OFDM sub channeling.


WiMAX supported to different frequency band considered as a different range.

In the year of 2005, an IEEE 802.16e variant was developed for supporting total mobility.


Following are the details of various IEEE 802.16 standard related to WiMAX.


1. 802.16
  • Spectrum - 10-66 GHz
  • Configuration  - Line of sight
  • Mobility - Fixed
  • Channel bandwidth - 20,25 MHz
  • Typical cell radius - 1-3 miles
  • Modulation - QPSK-16 QAM 64 QAM
  • Completion  - December 2001
2. 802.16a
  • Spectrum - 2-11 GHz
  • Configuration  - Non-Line of sight
  • Mobility - Fixed
  • Channel bandwidth - Selectable, 1.25-20 MHz
  • Typical cell radius - 3-5 miles
  • Modulation - total 256 subscriber, OFDM using QPSK, 16 QAM, 64 QAM, 256-QAM
  • Completion - January 2003
3. 802.16e
  • Spectrum - <6 GHz
  • Configuration  - Non-Line of sight
  • Mobility - Fixed
  • Channel bandwidth - 5 MHz planned
  • Typical cell radius - 1-3 miles
  • Modulation - 256 subscriber, OFDM using QPSK16, QAM, 64 QAM, 256-QAM
  • Completion - 2nd half of 2005
WiMAX architecture :

A WiMAX system consists of two major parts: Main part is to be (i) A WiMAX base station (ii) A WiMAX receiver.

Let us take a look at the WiMAX architecture to shown in the figure.

A WiMAX base station :

WiMAX base station is very similar to accessing a wireless access point in a Wi-Fi network, but the coverage is greater than to other networks.

In general WiMAX base station can provide a very large area up to a radius of 6 miles. A WiMAX base station consists of indoor electronics and as we know that WiMAX tower similar look like to a cell phone tower.

Each base station provides wireless coverage over an area called a cell. The WiMAX base station also uses a multiple antennas point in a different direction. This area covered by one antenna signal is called a sector.

The uplink and downlink channel are shared among the many subscriber stations in a given sector. WiMAX can also have support bursty data and high-quality telephone and high volume multimedia.

The uplink and downlink channels are divided into slots of equal size. A WiMAX frame takes multiple slots. The different frame takes a different number of slots. The downlink channel easy to subdivide into the connection as only the base station sends on that channel.

A WiMAX receiver : 

A WiMAX receiver may have a separate antenna or could be a stand-alone box or a PCMCIA  card present in your laptop or any other device. It is called Customer premise equipment (CPE).

In most of the cases, a simple plug and play terminal, similar to a DSL modem provides connectivity as shown in the figure.

For customer located several kilometers from the WiMAX base station, a self-install outdoor. The antenna may be required to improve transmission quality. 

For customer requesting a voice in addition to broadband services, specific CPE will allow the connection of standard or VoIP phones.


                   WiMAX architecture
Application of WiMAX :
  • It is a wireless alternative to many existing wired and late miles coverage deployments such as cable modem, digital subscriber line, T and E-carrier system and optical carrier technologies.
  • The most important application offered by WiMAX technology is business, Multiplayer interactive gaming, backhaul, consumer connectivity, large area coverage access.
  • Using WiMAX technology it can offer broadband wireless access at data rates of multiple Mbit/second to the end user and also within a range of several kilometers. So in this technology, the same radio technology will also offer high-speed data services to all the nomadic terminal like laptops. PDAs, and several other devices. 
  • IEEE 802.16 -Fixed users.
  • IEEE 802.16e - portable user.
  • Backhaul side - Point to point antenna is used to connect base station located across a long distance.
  • Last mile side - Residential and business subscriber are connected to the base station using point to multi-point antennas.
  • Large area coverage access side - WiMAX also offer broadband connectivity in larger areas.
Wi-Fi and WiMAX offer complementary solutions with Wi-Fi being suitable for short range and WiMAX being suitable for long-range outdoor connection.

WiMAX frequency

WiMAX could potentially be deployed in a variety of spectrum bands uses like 2.3 GHz, 2.5 GHz, 3.5 GHz, and 5.8 GHz. There are different types of WiMax frequency range listed below:

1. IEEE 802.16d (Fixed WiMAX)
Frequency band - 2-66 GHz
Range - 31 miles
Number of users - 1000

2. IEEE 802.16e (Mobile WiMAX)
Frequency band - 2-11 GHz
Range - 31 miles
Number of users - 1000

3. IEEE 802.11 (WLAN)
Frequency band - 2.4 -5.8 GHz
Range - 100 meters
Number of user - Dozens

4. IEEE 802.11  (Bluetooth)
Frequency band - 2.4 GHz
Range - 10 meters
Number of users - Dozens

WiMAX features

A wireless broadband solution that offers various features with a lot of flexibility in terms of potential service offering is WiMAX technology.
  • WiMAX support multipath.
  • IT provide up to 50 km of service area range.
  • WiMAX uses OFDM technology.
  • WiMAX support TDD and FDD.
  • WiMAX offer modulation and error correction.
  • Adaptive modulation enables while using WiMAX system to optimize the throughput based on the propagation conditions.
  • Very scalable bandwidth and high-speed data rate.
  • Flexible and dynamic per-user resource allocation.
  • Support for advanced antenna techniques.
  • Support for mobility.
  • Portable internet usage.
  • Quality of service support.
  • It is IP based architecture.
  • WiMAX is always best connected.

WiMAX architecture

As we know that the WiMAX system consists of two major parts: Main part is to be (i) A WiMAX base station (ii) And a WiMAX receiver.

Let us take a look at the WiMAX architecture to shown in the figure.

A WiMAX base station :

WiMAX base station is very similar to accessing a wireless access point in a Wi-Fi network, but the coverage is greater than to another network.

WiMAX base station can provide a very large area up to a radius of around 6 miles. A WiMAX base station(BS) consists of indoor electronics and as we know that WiMAX tower similar look like to a cell phone tower.

Each base station(BS) can provide wireless coverage over an area called a cell. The WiMAX base station can also use a multiple antennas point in a different direction. This area covered by one antenna signal called sector.

The uplink and also a downlink channel are shared among the many subscriber stations in a given sector. WiMAX can also have support bursty data and also provide high-quality telephone and high volume multimedia.

The uplink and also for downlink channels are divided into slots of equal size. A WiMAX frame takes multiple slots. Different frame takes a different number of slots. The downlink channel easy to subdivide into connection as only the base station sends on that channel.

A WiMAX receiver : 

A WiMAX receiver side may have a separate antenna or could be a stand-alone box or a PCMCIA card present in your laptop or any other device. It is called as customer premise equipment (CPE).

In most of the cases, a simple plug and play terminal, similar to a DSL modem provides connectivity as shown in the figure given below.

For customer located several kilometers from the WiMAX base station, a self-install outdoor. The antenna may be required to improve transmission quality. 

For customer requesting a voice in addition to broadband services, specific CPE will allow the connection of standard or VoIP phones device.


WiMAX architecture

WiMAX standard

We all know that the WiMAX system has been supporting IEEE 802.16, This standard is called IEEE  called 802.16, it was associated with 802.16a / REV d / e standard.

These standards were issued by IEEE standard 802.16 into the subgroup called  (802.16a/REV d/e) standard that originally covered the Wireless local loop (WLL) technologies with radio spectrum from 10 to 66 GHz. Recently were extended below 10 GHz.


In the year of January 2003, the approved IEEE standard 802.16a as an amendment to IEEE  standard 802.16 defining line of sight capability.


In the year of 2004, the IEEE 802.16 standard Revd was introduced to support basically indoor customer premises equipment through additional radio capabilities like antenna beamforming and OFDM sub channeling.


In the year of 2005, an IEEE standard 802.16e variant was developed for supporting mobility device.


Following are the details of various IEEE 802.16 standard related to WiMAX system listed below.


1. 802.16

  • Spectrum - 10-66 GHz
  • Configuration  - Line of sight
  • Mobility - Fixed
  • Channel bandwidth - 20,25 MHz
  • Typical cell radius - 1-3 miles
  • Modulation - QPSK-16 QAM 64 QAM
  • Completion  - December 2001
2. 802.16a
  • Spectrum - 2-11 GHz
  • Configuration  - Non-Line of sight
  • Mobility - Fixed
  • Channel bandwidth - Selectable, 1.25-20 MHz
  • Typical cell radius - 3-5 miles
  • Modulation - total number of 256 subscribers, OFDM using QPSK, 16 QAM, 64 QAM, 256-QAM
  • Completion - January 2003
3. 802.16e
  • Spectrum - <6 GHz
  • Configuration  - Non-Line of sight
  • Mobility - Fixed
  • Channel bandwidth - 5 MHz planned
  • Typical cell radius - 1-3 miles
  • Modulation - total number of 256 subscribers, OFDM using QPSK16, QAM, 64 QAM, 256-QAM
  • Completion - 2nd half of 2005

Application of WiMAX

Wi-Fi and WiMAX offer complementary solutions with Wi-Fi being suitable for short range and WiMAX being suitable for long-range outdoor connection.
  • It is a wireless alternative to many existing wired and late miles coverage deployments such as cable modem, digital subscriber line, T and E-carrier system and optical carrier technologies.
  • The most important application offered by WiMAX technology is business, Multiplayer interactive gaming, backhaul, consumer connectivity, large area coverage access
  • It can offer broadband wireless access at data rates of multiple in Mbit/second to the end user and within a range of several kilometers. 
  • And also the same radio technology will also offer high-speed data services to all nomadic terminal like laptops. PDAs, etc
  • IEEE 802.16 - Fixed users
  • IEEE 802.16e - portable user
  • back-haul - Point to point antenna are used to connect base station located across a long distance
  • Last mile - Residential and business subscriber are connected to the base station using point to multi-point antennas
  • Large area coverage access - also offer broadband connectivity in larger areas

Advantages and disadvantages of WiMAX

WiMAX stands for Worldwide Interoperability for Microwave Acess services brings long time term evolution in the wireless sector. It is similar to the Wi-Fi both create hot-spots. Wi-Fi technology can cover several 100 meters while covering a range of 40-50 km. It can also provide a wireless alternative to cable, DSL, and broadband access. The main advantages of WiMAX are that it allows high-speed wireless internet connection over the broad coverage area, while main disadvantages of WiMAX is still much bigger installation coast and also operational cost. Now let us check it out the information about the advantages and disadvantages of WiMAX to know more details about it.

Advantages of WiMAX :
  • A single location can serve hundreds of users
  • Single WiMax BS serves hundreds of users
  • Much faster deployment of the new user as compared to wired networks
  • It creates a volume opportunity for silicon suppliers
  • The speed of 10 Mbps at 10 kilometers with a line of sight
  • It is considered to be a cheaper alternative to broadband wired technologies viz. ADSL, cable modem etc
  • It is standardized, and also have same frequency equipment should work together
  • There exists a standard based, the stable platform upon which to rapidly add new capabilities so it is innovating more rapidly
  • Higher bandwidth
  • High coverage range
  • High speed can be achieve
  • Lower cost
  • Communication range up to 100 miles 
  • Does not require telephone lines
  • Provide mobility to a user with access to the internet
  • Design with better quality services
  • No SIM card requires
  • Non-line of sight connection
  • It works on an unlicensed frequency spectrum
  • Cellular like performance is achieved with mobile WiMAX
Disadvantages of WiMAX :
  • Big installation and operational cost
  • Multiple frequencies are used
  • A line of sight needed
  • Poor bandwidth when serving lots of clients
  • Higher latency
  • Unreliable service
  • Spectral limitation
  • Big delay
  • Big power consumption
  • Interference with other wireless signals
  • Hand over and roaming hard to achieve
  • Very power intensive technology  and  also have to require strong electrical support
  • Weather conditions like rain could cause interference
  • WiMAX is very power consuming
  • Multiple frequencies are used for WiMax deployment
  • WiMAX can offer up to 70 Mbps in the range of 70 miles with the moving station. So in practice, the situation is very different. So it is true that only in ideal circumstances with only one recipient
  • If there are many users in one sector, then they will have lower speed