WiMax over other technology

Over the last few years many types of broadband access technologies such as DSL (Digital subscriber loop) technology, HFC (Hybrid fiber coaxial) network, FBWAN (Fixed broadband wireless access network) have been implemented.
DSL is based on the wired technology, it is quite impossible to provide service to many locations such as rural areas, home users. Besides, an xDSL local loop provides services over long distance decreasing data rate that is a great problem for communication. Moreover, The DSL uses amplifiers, repeaters which are costly and risky and hard to maintain.
Some service providers are using WLL (Wireless Local Loop) for providing services in remote areas. WLL provides bandwidth from 35kbps to 70kbps for voice and data, which is inadequate for broadband services.
WiMAX has the following advantages over other technologies.
• Flexible Architecture: WiMax supports several system architectures, including Point- to-Point, Point-to-Multipoint, and ubiquitous coverage
• High Security: WiMax supports AES (Advanced Encryption Standard) and 3DES (Triple DES, where DES is the Data Encryption Standard). By encrypting the links between the BS and the SS, WiMax provides subscribers with privacy and security across the broadband wireless interface. Security also provides operators with strong protection against theft of service.
• Quick Deployment: Compared with the deployment of wired solutions, WiMax requires little or no external plant construction.
• Interoperability: WiMax makes it easier for end-users to transport and use their SS at different locations, or with different service providers. Interoperability protects the early Investment of an operator since it can select equipment from different equipment vendors.
• Portability: WiMax SS is powered up, it identifies itself, determines the characteristics of the link with the BS, as long as the SS is registered in the system database, and then negotiates its transmission characteristics accordingly.
• Mobility: The IEEE 802.16e amendment has added key features in support of mobility. Improvements have been made to the OFDM and OFDMA physical layers to support devices and services in a mobile environment. These improvements, which include Scaleable OFDMA, MIMO, and support for idle/sleep mode and hand-off, will allow full mobility at speeds up to 160 km/hr.
• Cost-effective: WiMax will drive costs down dramatically, and the resultant competitive pricing will provide considerable cost savings for service providers and end-users.
• Wider Coverage: WiMax dynamically supports multiple modulation levels, Including BPSK, QPSK, 16-QAM, and 64-QAM. WiMax systems are able to cover a large geographic area when the path between the BS and the SS is unobstructed.
• High Capacity: WiMax uses higher modulation (64-QAM) and channel bandwidth of currently 7 MHz. WiMax systems can provide significant bandwidth to end-users [27-29]

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WiMAX Applications

WiMAX attribute opens the technology to a wide variety of applications because of its high transmission rate and large range. It serves as a backbone for Wi-Fi for connectivity to the Internet. It can provide broadband connec-tivity over large coverage area as compared to 802.11 standard. WiMAX is a broadband wireless communication system, which enables convergence of mobile and fixed broadband networks through a common wide-area and
flexible network architecture. The mobile WiMAX air interfaces use OFDMA for improvement in multiple path interference in nonline-of-sight environ-ment. Its ability to support both line-of-sight and nonline-of-sight connections makes it suitable for ubiquitous services offered in rural and urban areas alike. High speed and symmetrical bandwidth satisfy the needs of individual customers, public administration, and enterprises of all sizes . The technology also provides fast and cheap broadband access to markets that lack infrastructure (fiber optics or copper wire), such as rural and unwired countries. Currently, several companies offer proprietary solutions for wireless broadband access, many of which are expensive because they use chipsets from adjacent technologies, such as 802.11. Early field experiments in various countries confirm that expectations in terms of coverage, performance, and usage scenarios are indeed justified. WiMAX has changed the scenario of wireless broadband from proprietary solutions to a standards-based industry. It supports fast Internet access, high-quality audio and video communications, education, entertainment, telemedicine, telemetering, and telesurveillance. WiMAX supports personal broadband services on both fixed and mobile settings because of its high spectral efficiency and wide channelization as well as the advanced antenna technologies. This flexibility in providing both fixed and mobile access within the same infrastructure is unprecedented among wireless technologies, which are typically optimized for either mobile or fixed access.

Figure 1: WiMAX Applications.

1 Cellular Application

The main merit of WiMAX is in the area of mobile service. For a large number
of cell phone operators the major monthly operating expense on T1 backhaul
that supports their base stations as shown in Figure 2. A WiMAX substitute
for the cell phone infrastructure could be operated with as little as 10% of T1
backhaul. While replacing a cell phone infrastructure with WiMAX one can
send a large amount of data because the bandwidth of WiMAX is far greater.
The data can include voice, mobile data, TV, videoconferencing, video on
demand, etc.

Figure 2: Cellular architecture using T1 as back haul.

2 WiMAX Military Applications

As WiMAX uses higher frequencies than current military and commercial communications, existing antenna towers share a WiMAX cell tower without compromising the current communication services. WiMAX can be used to support training and war game simulations. An initial deployment of WiMAX has already been constructed by the U.S. Army Fortdix. The U.S. army is testing prestandard WiMAX gear and Xacta secure wireless system from Telos Corporation in Fort Carson in Colorado for point-to-point and point-to-multipoint communications.

The forces at different locations can be connected through WiMAX as shown in Figure 3. They can exchange their information from multiple sources, rapidly and flexibly. This is ideally suited to meet the demands of the tactical defense operations model. The mobile antennas can be attached to a vehicle and the latest data can be provided to the soldiers. A communication from command centers can be made to the different centers, regardless of the distance, and directions can be delivered to the army people. The best part of WiMAX is the handover strategy. It uses “make-before-break’’ sequence rather than “break-before-make’’ sequence.

Figure 3: WiMAX architecture for Military Applications.

3 Medical Applications

In an emergency situation where patients require immediate medical support,
WiMAX can serve as the foundation of a mobile hospital. It can be a platform
for e-health. In e-health services a doctor can diagnose his patient at some

far location with the help of e-media. The doctor ’s computer equipped with the medical instruments can be connected to the patient’s computer through WiMAX.

A patient at location 2 can send his reports, for example, blood pressure, through his computer to the doctor ’s computer as shown in Figure 4. The doctor can diagnose the patient’s disease and give him necessary treatment. The connection between the doctor and the patient is through the Internet. The two computers are connected through WiMAX.

Figure 4: Medical Applications.

Also in some emergency situations, a video consultation with a doctor can be set up and the doctor can instruct the paramedic to mobilize the victim without inflicting further damage. With WiMAX, mobile hospital vans can communicate data and other instructions within a disaster zone. The information through WiMAX can be encrypted and made secure. So in diverse conditions WiMAX can provide to the patient valuable information recommended by doctors over large distances.

4 Security Systems

WiMAX offers a simple and convenient system for security on the borders and within the country to save the nation from some terrorist attacks.
A video camera can be mounted on WiMAX antenna or some separate pole, which can be controlled at the headquarters as shown in Figure 5. This camera will keep an eye over the different activities of the enemies thereby assisting in security planning. It can also be used to provide video surveillance of smuggling and illegal entries along the borders.

WiMAX is a medium for the security of not only army but also navy.
Through the use of WiMAX one can monitor the activities on the sea. A video
camera that is mounted on the antenna of a shipyard can monitor the nearby
activities and report to the headquarter as shown in Figure 5. So WiMAX
can effectively monitor shipyards, nuclear facilities, and key transport routes.

Figure 5: WiMAX architecture for security applications.

5 Disaster Applications

WiMAX can be used in recovery from disasters, such as earthquakes and floods, when the wired networks break down. It helps in connecting the disaster location to telephone services, hospitals, and other important services. In recent hurrican disasters, WiMAX networks were installed to help recovery missions. WiMAX can enable efficient communications with emergency operation centers regardless of the distance. Similarly, WiMAX is used as backup links for broken wired links.

6 Connectivity of Banking Networks

The banking system where security is the major concern can be connected
through the WiMAX networks. Owing to the broad coverage and large con-
nectivity, WiMAX can connect a large number of diversely located banks and

ATM locations. WiMAX networks provide not only
security but also a high degree of scalability. Through WiMAX, telephone
voice, financial transactions, email, Internet, intranet, surveillance, and close
circuit television (CCTV) type of data can be communicated easily.

7 Public Safety

Through WiMAX, public safety agencies can be connected with each other. During any mishap, such as accident, fire, etc., the control office can send its command to the police station, hospital, or fire brigade office. The corresponding agencies immediately can connect to the accidental location by using WiMAX-enabled vehicles.

The video images and data from the site of accidental location can be sent to corresponding agencies. These data can be examined by the experts of the emergency staff and accordingly prescription can be communicated. A video camera in the ambulance can send the latest images of the patient before the ambulance reaches the hospital so that the doctors can get ready for further action quickly. Through WiMAX, a fireman can download the data about the best route to a fire scene.

8 Campus Connectivity

Campus system requires high data capacity, a large coverage, and high
security. WiMAX can connect various blocks within the campus.
Through this connectivity voice, data, and video information can be sent to
various interconnecting blocks as shown in Figure 6. It is very difficult to
connect various blocks through cables because the lead time to deploy a wired
solution is much longer than the lead time to deploy a WiMAX solution.

Figure 6: WiMAX campus connectivity.

9 Educational Building Connectivity

WiMAX can connect boards, colleges, schools, and the main head offices as shown in Figure 7. Through this, telephone voice, data, email, Internet, question papers, intranet, video lectures, presentations, and students’ results can be communicated at a very high rate.

By video conferencing the students can interact with the teachers of another institution (i.e., engineering college, medical colleges, etc.) like as Figure 7. A camera at college 1 delivers real-time classroom instruction to college 2, allowing the colleges to simultaneously deliver instruction from a recognized subject matter expert to a large

Figure 7: WiMAX educational building connectivity.

number of students. Colleges and schools in rural areas can be connected through WiMAX with other institutions having better facilities through WiMAX so that remotely located students can also be benefitted.

Hence it can be concluded that this broadband wireless standard supports
both the computer and telecom industries worldwide, making this technology
highly cost effective. It helps enterprises, consumers, public services, and peo-
ple in urban and rural areas over a large range with high data throughput.

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Simulation of 802.16E WiMAX Systems

WiMAX is a telecommunication technology aimed at providing wireless data over long distances in a variety of ways, from point-to-point links to full mobile cellular type access. It is a certification
mark used for products based on the IEEE 802.16 family of standards, which specifies a wireless metropolitan-area network technology. 802.16e is an amendment to 802.16, which uses OFDMA and provides.



















Figure 1: WiMAX Network

• Design a WiMAX 802.16e system in MATLAB Simulink

• Simulate the system using MATLAB Simulink

• Look for options for better system performance

• Transmitter transmits the orginal data using OFDMA

• Receiver performs estimation and recovers the orginal

data from the receiver OFDMA sysbol

• Channel simulates different cases such as direct input

AWGN, and frequency-select fading

Simulation Result

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Dynamic simulation of mobile WiMAX networks

The main aim of the present work has been to develop a
simulator to study WiMAX 802.16e performance. The use of
simulation tools in the planning of resources in radio systems
for mobile communications in general, and in particular in
WiMAX, is essential if it is to act as a way of predicting and
analyzing the performance of effective planning. Evaluating
the performance simulation of these systems has a key role in
the process of scaling at various planning stages.
The simulation tool developed can be characterized by
three successive stages, as illustrated in Figure II-1:
Configuration, Simulation and Analysis.
This simulator is based upon and greatly extends an existing
UMTS simulator [3]. The main changes made in the structure
of the simulator may be found in the Radio Prediction Module
and System Simulation Model. They have all been changed
owing to the fact that a different kind of technology is
involved. The Analysis Modules have been adapted so as to
assess the performance of WiMAX technology and a new
module has also been added to apply different algorithms to
the resource allocation, called the Scheduling Algorithms
module











Fig. 1: Characterization of the Simulation tool

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WiMAX Simulation Tools List

For the best thing in WiMax is right calculation and optimization of the Radio Frequency and Capacity, Network planning, to do those things you have to choose the best simulation tool which works on the wimax system. I have tried to write a list of all the famous and mostly used simulation and planning tools in the undermentioned list. Even you can try freeware soft wares to simulate your network design.

1. MATLAB -Web Site
2. OPNET tool - web site
3. Planet EV - web site
4. EDX (SignalPro) - web site
5. Provision Communication - web site
6. Radio Mobile (Freeware) - web site 1 web site 2 web site 3
7. Atoll - web site
8. CelPlan - web site
9. ICS Telecom - web site
10. Asset 3G/WiMAX - web site
11. Winprop - web site
12. Volcano Siradel - web site
13. NS-2 (Freeware) - web site
14. NS-3 (Freeware) - web site
15. Qualnet - web site
16. NCTuns Network Simulator and Emulator - web site

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WiMAX Forum

IEEE 802 standards provide only the technology. It is then needed to have other organisms for the certification of conformity and the verification of interoperability. In the case of IEEE 802.11 WLAN, the Wireless Fidelity Alliance (WiFi or Wi-Fi) Consortium had a major role in the success of the WiFi technology, as it is now known. Indeed, the fact that two WiFi certified IEEE 802.11 WLAN devices are guaranteed to work together paved the way for the huge spread of WiFi products.

The certification problem was even more important for WiMAX as many product manufacturers claimed they had verified the 802.16 standard. The WiMAX (Worldwide Interoperability for Microwave Access) Forum (http://www.wimaxforum.org) was created in June 2001 with the objective that the WiMAX Forum plays exactly the same role for IEEE 802.16 as WiFi for 802.11. The WiMAX Forum provides certification of conformity, compatibility and interoperability of IEEE 802.16 products. After a period of low-down, the WiMAX Forum was reactivated in April 2003. Some sources indicate this latter date as the date of the creation of the WiMAX Forum. Intel and Nokia, along with others, played a leading role in the creation of the Forum. Then Nokia became less active, claiming that it wished to concentrate on 3G. However, Nokia is again an active player of WiMAX.

WiMAX Forum members are system and semiconductors manufacturers, other equipment vendors, network operators, academics and other telecommunication actors. A complete list of the WiMAX Forum members can be found on the Forum Member Roster web page. A nonexhaustive list of WiMAX members is proposed in Table 1.

Table 1: Some WiMAX Forum members
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Manufacturers	Airspan, Alcatel, Alvarion, Broadcom, Cisco, Ericsson. Fujitsu, Huawei, Intel, LG, Lucent, Motorola, Navini, Nokia, Nortel, NEC Proxim, Sagem, Samsung, Sequans, Siemens, ZTE, etc.
Service providers	British Telecom, France Telecom, KT (Korea Telecom), PCCW, Sprint Nextel, Telmex, etc.

The site of the WiMAX Forum indicates that its objective is to facilitate the deployment of broadband wireless networks based on the IEEE 802.16 standard by ensuring the compatibility and interoperability of broadband wireless equipment.

1 WiMAX Forum Working Groups

The WiMAX Forum is organised into Working Groups (WGs).The scope of these WGs is given in Table 2, as indicated on the WiMAX Forum website.

Table 2: WiMAX Forum working groups. As of July 2006, the Forum website also indicates the Global Roaming Working Group (GRWG)
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Working group name	Scope
Application Working Group (AWG)	Defines applications over WiMAX that are necessary to meet core competitive offerings and are uniquely enhanced by WiMAX
Certification Working Group (CWG)	Handles the operational aspects of the WiMAX Forum certification program; interfaces with the certification lab(s); selects new certification lab(s).
Marketing Working Group (MWG)	Promotes the WiMAX Forum, its brands and the standards that form the basis for worldwide interoperability of BWA systems
Network Working Group (NWG)	Creates higher-level networking specifications for fixed, nomadic, portable and mobile WiMAX systems, beyond what is defined in the scope of 802.16; specifically, the NWG defines the architecture of a WiMAX network
Regulatory Working Group (RWG)	Influences worldwide regulatory agencies to promote WiMAX-friendly, globally harmonised spectrum allocations
Service Provider Working Group (SPWG)	Gives service providers a platform for influencing BWA product and spectrum requirements to ensure that their individual market needs are fulfilled
Technical Working Group (TWG)	Develops conformance test specifications and certification services and profiles based on globally accepted practices to achieve worldwide interoperability of BWA systems

2 WiMAX Forum White Papers

The WiMAX Forum regularly publishes White Papers. These are a very useful information source about WiMAX, freely available on the Forum website. In Table 3, a nonexhaustive list of White Papers is proposed (until July 2006).

Table 3: WiMAX Forum (http://www.wimaxforum.org) White Papers, last update: July 2006. Table was drawn with the help of Ziad Noun
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Title	Date of latest version	Number of pages	Brief description
IEEE 802.16a standard and WiMAX -Igniting BWA	Date not mentioned	7	An overview of IEEE 802.16a standard, its PHY and MAC layers; talks also about the WiFi versus WiMAX scalability
Regulatory position and goals of the WiMAX Forum	August 2004	6	Describes the goals of WiMAX Forum (interoperability of broadband wireless products); describes also the initial frequency bands (license and license exempt)
Business case for fixed wireless access in emerging markets	June 2005	22	Describes the characteristics of emerging markets and discusses the service and revenue assumptions for business case analysis (urban, suburban, rural)
WiMAX deployment considerations for fixed wireless access in the 2.5 GHz and 3.5 GHz licensed bands	June 2005	21	About the licensed spectrum for WMAN, the radio characteristics, the range and the capacity of the system in different sccnarios (urban, suburban. etc.)
Business case models for fixed broadband wireless access based on WiMAX technology and the 802.16 standard	October 2004	24	Describes the WiMAX architecture and applications, the business case considerations and assumptions and the services oftered by WiMAX
Initial certification profiles and the European regulatory framework	September 2004	4	Describes the profiles currently identified for the initial certification process and the tentative profiles under consideration for the next round of the certification process
WiMAX's technology for LOS and NLOS environments.	August 2004	10	About the characteristics of OFDM and the other solutions used by WiMAX to solve the problems resulting from NLOS (subchannelisation, directional antennas, adaptive modulation, error correction techniques, power control, etc.)
Telephony's ‘Complete Guide to WiMAX’	May 2004	10	About WiMAX marketing and policy considerations
What WiMAX Forum certified products will bring to Wi-Fi	June 2004	10	Why WiFi is used in WiMAX, the OFDM basics, the 802.16/HiperMAN PHY and MAC layers, the operator requirements for BWA systems and the products certification
What WiMAX Forum certified products will bring to 802.16	June 2004	6	The certified products: where do WiMAX Forum certified products fit and why select them?
Fixed, nomadic, portable and mobile applications for 802.16-2004 and 802.16e WiMAX networks	November 2005	16	Compares the two possibilities of deployment for an operator: fixed WiMAX (802.16-2004) or mobile WiMAX (802.16e)
The WiMAX Forum certified program for fixed WiMAX	March 2006	15	Describes the general WiMAX certification process and specifically the fixed WiMAX system profiles certifications
Third WiMAX Forum plugfest - test methodology and key learnings	March 2006	18	Describes WiMAX March 2006 plugfest
Mobile WiMAX - Part I: a technical overview and performance evaluation	March 2006	53	Technical overview of 802.16e system (mobile WiMAX) and the corresponding WiMAX architecture
Mobile WiMAX - Part II: a comparative analysis	May 2006	47	Compares elements between mobile WiMAX and presently used 3G systems (1xEVDO and HSPA)
Mobile WiMAX: the best personal broadband experience!	June 2006	19	Provides mobile WiMAX advantages in the framework of mobile broadband access market
Executive summary: mobile WiMAX performance and comparative summary	July 2006	10	Brief overview of mobile WiMAX and summary of previous White Papcr performance data

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Physical Layer or The Physical Layer of WiMAX

The 802.16 Physical Transmission Chains

The modulation and OFDM transmission are the major building blocks of the WiMAX PHYsical Layer. The transmission chains of WiMAX are described for both OFDM and OFDMA PHYs.

1 The Global Chains

The PHY transmission chains of OFDM and OFDMA are illustrated in Figures 1 and 2. The blocks are the same with the small difference that OFDMA PHY includes a repetition block. The modulated symbols are then transmitted on the OFDM orthogonal subcarriers. In the following, WiMAX channel coding building blocks are described.

Figure 6.1: OFDM PHY transmission chain

Figure 6.2: OFDMA PHY transmission chain

2 Channel Coding

The radio link is a quickly varying link, often suffering from great interference. Channel coding, whose main tasks are to prevent and to correct the transmission errors of wireless systems, must have a very good performance in order to maintain high data rates. The 802.16 channel coding chain is composed of three steps: randomiser, Forward Error Correction (FEC) and interleaving. They are applied in this order at transmission. The corresponding operations at the receiver are applied in reverse order.

3 Turbo Coding

Turbo codes are one of the few FEC codes to come close to the Shannon limit, the theoretical limit of the maximum information transfer rate over a noisy channel. The turbo codes were proposed by Berrou and Glavieux (from ENST Bretagne, France) in 1993. The main feature of turbo codes that make them different from the traditional FEC codes are the use of two error-correcting codes and an interleaver. Decoding is then made iteratively taking advantage of the two sources of information

4 Transmission Convergence Sublayer (TCS)

The Transmission Convergence Sublayer (TCS) is defined in the OFDM PHY Layer and the Non-WiMAX SC PHY Layer. The TCS is located between the MAC and PHY Layers. If the TCS is enabled, the TCS converts MAC PDUs of variable size into proper-length FEC blocks, called TC PDU.

The TCS is an optional mechanism for the OFDM PHY. It can be enabled on a preburst basis for both the uplink and downlink through the burst profile definitions in the uplink and downlink channel descriptor (UCD and DCD) messages respectively. The TCS_ENABLE parameter is coded as a TLV tuple in the DCD and UCD burst profile encodings. At SS initialisation, the TCS capability is negotiated between the BS and SS through SBC-REQ/SBC-RSP MAC messages as an OFDM PHY specific parameter. The TCS is not included in the OFDMA PHY Layer.

Finally, the burst profiles of OFDM and OFDMA PHY, an important building block of IEEE 802.16 MAC layer, are described:

5 Burst Profile

The burst profile is a basic tool in the 802.16 standard MAC Layer. The burst profile allocation, which changes dynamically and possibly very fast, is about physical transmission. Here the parameters of the burst profiles of WiMAX are summarised. The burst profiles are used for the link adaptation procedure.

5.1 Downlink Burst Profile Parameters

The burst profile parameters of a downlink transmission for OFDM and OFDMA PHYsical layers are proposed in Table 1. The parameter called FEC code is in fact the Modulation and Coding Scheme (MCS). For OFDM PHY, there are 20 MCS combinations of modulation (BPSK, QPSK, 16-QAM or 64-QAM), coding (CC, RS-CC, CTC or BTC) and coding rate (1/2, 2/3, 3/4 and 5/6). The most frequency-use efficient (and then less robust) MCS is 64-QAM (BTC) 5/6. For OFDMA PHY, there are 34 MCS combinations of modulation (BPSK, QPSK, 16-QAM or 64-QAM), coding (CC, ZT CC, CTC, BTC, CC with optional interleaver) and coding rate (1/2, 2/3, 3/4 and 5/6).

Table 1: Downlink burst profile parameters for OFDM and OFDMA PHYsical layers
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Burst profile parameter	Description
Frequency (in kHz)	Downlink frequency
FEC code type	Modulation and Coding Scheme (MCS); there are 20 MCSs in OFDM PHY and 34 MCSs in OFDMA PHY (as updated in 802.16e)
DIUC mandatory exit threshold	The CINR at or below where this burst profile can no longer be used and where a change to a more robust (but also less frequency-use efficient) burst profile is required. Expressed in 0.25 dB units.
DIUC minimum entry threshold	The minimum CINR required to start using this burst profile when changing from a more robust burst profile. Expressed in 0.25 dB units
TCS_enable (OFDM PHY only)	Enables or disables TCS

5.2 Uplink Burst Profile Parameters

The burst profile parameters of an uplink transmission for an OFDM PHY and an OFDMA PHY are proposed in Tables 2 and 3 respectively.

Table 2: Uplink burst profile parameters for the OFDMA PHYsical Layer
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Burst profile parameter	Description
FEC type and modulation type	There are 20 MCSs in OFDM PHY
Focused contention power boost	The power boost in dB of focused contention carriers
TCS_enable	Enables or disables TCS

Table 3: Uplink burst profile parameters for the OFDMA PHYsical Layer
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Burst profile parameter	Description
FEC type and modulation type	There are 52 MCSs in OFDMA PHY
Ranging data ratio	Reducing factor, in units of 1 dB, between the power used for this burst and the power used for CDMA ranging encoded as a signed integer

5.3 MCS Link Adaptation

The choice between different burst profiles or, equivalently, between different MCSs is a powerful tool. Specifically, choosing the MCS most suitable for the state of the radio channel, at each instant, leads to an optimal (highest) average data rate. This is the so-called link adaptation procedure. In the following chapters the MAC procedures that can be used for the implementation of link adaptation are described. The link adaptation algorithm in itself is not indicated in the 802.16 standard. It is left to the vendor or operator.

The order of magnitudes of SNR thresholds can be obtained from Table 4, proposed in the standard for some test conditions. These SNR thresholds are for a BER, Bit-Error Rate, measured after the FEC, that is smaller than 10⁻⁶.

Table 4: Received SNR threshold assumptions , Table 266. (From IEEE Std 802.16-2004 . Copyright IEEE 2004, IEEE. All rights reserved.)
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Modulation	Coding rate	Receiver SNR threshold (dB)
BPSK	1/2	6.4
QPSK	1/2	9.4
QPSK	3/4	11.2
QAM-16	1/2	16.4
QAM-16	3/4	18.2
QAM-64	1/2	22.7
QAM-64	3/4	24.4

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