Last December the IEEE ratified the 802.16e amendment to its 802.16-2004 Air Interface Standard. 802.16e adds mobility to WiMAX, and now that mobility is ratified, the WiMAX Forum's Mobile Technical Group is developing the system profiles which will define the mandatory and optional features of the amendment that are necessary to build a mobile WiMAX-compliant air interface. One technology which is included in the amendment is scalable OFDMA technology, aiming to improve multi-path performance in non-line-of-sight environments. The 802.16e amendment calls for Scalable OFDMA to support scalable channel bandwidths from 1.25 to 20 MHz, but note that the Mobile WiMAX Release-1 profiles will cover only 5-, 7-, 8.75-, and 10-MHz channel bandwidths for licensed spectrum allocations in the 2.3-, 2.5-, and 3.5 GHz frequency bands. Remember that the 2.3 GHz band has been allocated in Korea for WiBro, the 2.5 GHz band is available in the U.S. and the 3.5 GHz band is available in many other countries.
To bring certified products to market we need certification test labs, and if we hope to see certified products by the end of the year, these labs have to be operational by mid-year. This is the WiMAX Forum's second front. Last year, Centro de Tecnologia de las Comunicaciones (CETECOM) set up a certification test lab for fixed WiMAX systems. The lab is now certifying WiMAX-compliant products for fixed services, specifically products for the licensed 3.5 GHz band and licensed-exempt 5.8 GHz band. The Forum is setting up a second certification lab in Korea. Both Spanish and Korean labs are expected to be operational for mobile WiMAX profile certifications by the third quarter this year.
Here are a couple of developments along these lines:
- Last month the WiMAX Forum signed a contract with Aeroflex and CETECOM to develop the protocol conformance test solution. The first product that the Aeroflex/CETECOM partnership will bring to market is a base station emulator to be used for protocol conformance testing of mobile stations executing ETSI approved TTCN-3 test cases.
- picoChip will supply its multi-core processor arrays and software to be incorporated into the protocol conformance tester. picoChip's PC102 picoArray and PC 8530 software stack will be used to simulate a complete link when characterizing the base station and subscriber station. Joaquin Torrecilla, CTO of CETECOM, commented that "picoChip's wireless solution provides us with a single, very sophisticated and flexible architecture that can be customized for each standard and protocol. We will be able to upscale or upgrade our platform to meet new requirements, or add capability such as support for MIMO, simply by updating the software."
For more on mobile WiMAX certification test labs:
- see Chris Everett's Telecomasia report
ALSO: Japanese mobile operator NTT DoCoMo has submitted an application to the regulator for a permit to conduct experimental outdoor wireless tests of WiMAX. Report