WiMAX has been one of your popular search topics this year on RF DesignLine. Recently I had the opportunity to talk with some people who are very active in this market: Li Cui, Product Manager Real-Time Signal Analyzer Product Line, Tektronix; Eric Toulouse, Freescale Semiconductor, RF Division; and Walter Lau, Director, Wireless Data Products, Maxim. I've collected some of the highlights of their remarks, and have also included some links below to some popular WiMAX items appearing on the site this year.
What would you most like RF designers to understand about WiMAX?
Cui:Design challenges extend beyond compliance testing of components and systems. Tools exist that can help engineers discover anomalies in the generation of both Fixed and Mobile WiMAX, such as digital predistortion (DPD), DSP, and EMI problems. RF designers [need to] easily discover and troubleshoot inter-cell or other field interferences, especially for those unexpected transient interference troubleshooting applications.
Toulouse: High power designs WiMAX specifications are very tight compared to W-CDMA, specifically on linearity, but high frequency operations (up to 3.6 GHz) makes it more difficult to reduce performance spread over volume.
Lau:Designing a WiMAX radio no longer requires that you use discrete components, or even a 2-chip superheterodyne radio with SAW filters. Now you can design the radio with [a] single-chip Zero-IF transceiver, a 3rd party PA, and no SAW filter is required.
What is the status of WiMAX?
Cui: Recent events in the US have been somewhat disappointing for WiMAX's adoption,however, we are still seeing good design activity in Europe and Asia.
Toulouse:Initial system deployment to support trials in various part of the world, but for fixed and mobile applications.
Lau:Some pre-WiMAX networks are already in operation (ie, Clearwire in the US) and some 16d WiMAX fixed network also in operation (ie, VSNL in India). There are numerous trials on-going worldwide using 802.16e MIMO. The US and Korea will be the first markets for mobile 802.16e WiMAX.
What are the remaining technical challenges for WiMAX?
Cui:Field interference is a significant remaining challenge. Either WiMax interference to other systems, e.g. satellite and radar on C band, or the interference from other systems to WiMax. A "two-in-one" test equipment that can do both the in-lab RF compliance testing and field interference troubleshooting will be an ideal tester to help to cope with this challenge.
Toulouse:For WiMax to be competitive, the cost of deploying and operating networks must be equivalent or ideally lower than current systems. For the RF section, this means low cost power amplifiers and high efficiency.
Lau:Balancing the range/data throughput performance with battery life. For desktop CPE modems, this is much less of an issue. For portable devices such as smartphones and PMPs, the battery life is much more critical.
The nuts and bolts of WiMAX--Part I
The nuts and bolts of WiMAX--Part II
Cut through the confusion of mobile WiMAX
Implementing cost-effective RF subsystems for mobile WiMax
Practical tips on making WiMAX field measurements, Part 1
Practical tips on making WiMAX field measurements, Part 2
The challenge of developing mobile WiMax-compliant systems
Solving the coexistence of WiMAX, Bluetooth and WiFi in converged handsets
Build WiMAX base stations and subscriber stations
WiMAX chipset roundup
Certification begins for mobile WiMAX products
Integrated front-end module targets WiMAX devices
Integrated silicon flows at WiMax world
Mobile WiMax moving the chipset market, asserts In-Stat
WiMax Gets Two New Friends: Cisco And The United Nations