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OFDM/OFDMA Audio Visual Tutorial for WiFi and WiMAX


Movies for Individual Topics plus PDF files for each subject.
Theory and implementation
High Quality Audio and Visual Movie with Scrubbing Support.
PDF for hundreds of illustrations with design equations included for each AV Movie.
IEEE 802.11a, IEEE 802.16-2004, IEEE 802.16e.
Full development of OFDM with Acquisition.
OFDMA as implemented in WiMax (IEEE 802.16-2004, IEEE802.16e) .
System Engineering for OFDM.
Complete description and tutorial on Convolutional Encoding with Viterbi Decoding.
Introduction to Reed Solomon Coding.
Downloadable for off-line viewing
Easy to follow but Includes in depth technical development.
References provided for further detail.


OFDM Tutorial Summary

The OFDM Tutorial goes in depth into the theory and implementation of OFDM wireless communication systems. Starting with the treatment of multipath fading channels, OFDM is introduced as a bandwidth efficient robust communication system for multipath fading channels. Using IEEE 802.11a as a basis, a full OFDM system is described in both theory and implementation. In particular, detailed description of acquisition including packet detection, timing synchronization, carrier frequency offset estimation and correction and channel estimation and equalization is presented along with implementation details.

A full development of 256 point FFT based OFDM in WIMAX and IEEE 802.16-2004 is presented. This includes the description of Time Division Duplex(TDD) and ranging.

OFDMA as implemented in IEEE 802.16-2004 and scalale OFDMA is fully developed.


The tutorial also includes full description and tutorials on Forward Error Correction (FEC) including Convolutional Encoding and Viterbi Decoding and an introduction to Reed-Solomon coding.

The AV OFDM Tutorial includes many aspects of System Engineering related to the design of OFDM systems. A direct conversion receiver and transmitter are developed including full descriptions of the tight interaction of the baseband and the analog Radio. This includes Automatic Gain Control (AGC) and tradeoffs in complexity between the Radio and Baseband.

Both large scale and small scale (microscopic) aspects of the multipath fading channel are covered, This includes the Stanford University Interim (SUI) channel models for fixed wireless access networks and models for mobile wireless access. A full development of fading due to vehicle motion including the derivation of the doppler power spectral density is presented.

The material is fully referenced.

OFDM/OFDMA AV Tutorial Outline


OFDM with IEEE 802.11a Implementation
Topic Duration
Multipath Fading Channels
Digital Communications Basics
OFDM (Orthogonal Frequency Division Multiplex)
Intersymbol Interference and Equalization
Cyclic Prefix for OFDM
Frequency Domain Equalization
Physical Layer Frame Organization
Carrier and Pilot Allocation
Carrier Frequency Offset(CFO) Estimation and Correction
Packet Detection and Synchronization
Forward Error Correction (FEC) Convolutional Encoding and Viterbi Decoding
Pilot Tracking


IEEE 802.16-2004 and IEEE802.16e
Topic Duration
WirelessMAN-OFDM Physical Layer (256 Point FFT)
WirelessMAN-OFDMA Physical Layer
Scalable OFDMA
Introduction to Reed-Solomon Coding


Channel Models
Topic Duration
Mobile Fading Channel (Doppler Spread)
Channel Models for IEEE 802.16 Fixed and Mobile Wireless Access Networks


System Engineering
Topic Duration
Direct Conversion Receiver
ADC Requirements
Adjacent Channel Interference
SNR and Noise Figure
Phase Noise




The AV OFDM/OFDMA Tutorial will enable you to speed up OFDM product design, understand the issues involved in designing OFDM/OFDMA systems and interact between team members in the course of product development and network deployment.

Professional Benefits
System Engineers The tutorial leaves no stone unturned. The sections on acquisition and AGC and impairments should be of great value in designing OFDM systems to meet requirements.
Architects Whether experienced in OFDM or newly responsible for the architecture of an OFDM communication system, this tutorial has all the theory and implementation to kick start the project
MAC Embedded Software Developers Get a head start on development with in depth coverage of physical layer for OFDM and OFDMA.
RTL Designers Now you can get all the theory and implementation that is the basis for developing and integrating RTL blocks in an OFDM/OFDMA system.
Architecture Verification With the material provided you can understand what needs to be done to verify Silicon Designs based on OFDM. Especially, by better understanding acquisition within a multipath environment and also AGC you can focus on tests vectors that verify designs over multipath fading channels, and with jammers.
Network Design and Deployment Engineers System Engineering/Multipath Channel Models/Path Loss/Sensitivity, SNR. Insight into how Physical Layer impacts performance.
Project Managers Get an overview of a complete block by block description of an OFDM system so that you can better manage the project. Also since the concepts are described in detail you can get a better grip on OFDM and OFDMA in order to cover all the basis in product development and better interact with your team.
Marketing and Sales See how OFDM and OFDMA are able to provide robust and reliable communication over wireless multipath fading channels. Grasp the concepts behind OFDM and OFDMA.



Dr. Sasan Ardalan (Extra Class Amateur Radio, KG4WUP) received his Ph.D. from North Carolina State University in 1983. He was an Associate Professor at NC State in 1991. In 1995 he joined IBM and was a leader in the ITU standards on high speed voice band modems. He joined ABB in 1997 and lead the design of a new wireless system for automatic meter reading. He also deployed early high speed digital wireless systems for metropolitan wide communications in 1998. He also designed and implemented a mobile crew management system. He was an Adjunct Professor at Duke University where he developed new courses on wireless communications and wireless Internet. Dr. Ardalan was responsible for the development of a frequency-stepped double side-band suppressed carrier microwave radar system for NASA. He led the development effort for an end to end C based simulation of an IEEE 802.11a OFDM system for the Capsim block diagram simulation tool in 2001-2002. He joined Intel in 2003-2006 where he was chief systems engineer in the development of US based WiFi products. In 2006 he founded Silicon DSP Corporation in Portland, Oregon. He has many publications in refereed journals. He has 7 issued US Patents. He was awarded the Best Teacher Award, Dept. of Electrical and Computer Engineering, NC State University, 1991.


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