Wednesday, 4 November 2009

Mobile WiMAX technology and network evolution roadmap.

The Mobile WiMAX Release 1.0 System Profile, based on 802.16e or 802.16-2005, was completed in late 2006, and the radio-level certification of products began in 2007. The certification follows a phased approach to address deployment priorities and vendor readiness. System Profile Release 1.0 includes all 802.16-2005 mandatory features, and also requires some of the optional features needed for enhanced mobility and QoS support. This system profile is based on OFDMA, and enables downlink and uplink multiple-input multipleoutput (MIMO) as well as beamforming (BF) features. The release 1.0 system profile is defined only for the TDD mode of operation, with more focus on 5 and 10 MHz bandwidths in several band classes in 2.3 GHz, 2.5 GHz ,and 3.5 GHz bands, but it also includes 8.75 MHz specifically for Korea.

The WiMAX certification for the release 1.0 profile started with a Wave 1 subset, excluding MIMO and a few optimization features, to enable early market deployments. This was followed by Wave 2, which progressively adds more and more feature tests over time based on vendors and testing tool availability. The early phases of certification were also limited to MAC and PHY layer conformance and interoperability testing, which will be expanded to add networklevel testing.

Meanwhile, the development of WiMAX Forum Network Release 1.0 was completed in 2007, based on which the specific network-level device conformance testing as well as infrastructure interoperability testing projects were initiated. The goal was to ensure e2e interoperability of WiMAX devices with networks and also ensure multivendor plug and play network infrastructure deployments. Release 1.0 defines the basic architecture for IP-based connectivity and services while supporting all levels of mobility. Based on operators’ requirements for advanced services and new market opportunities to be more competitive with evolved 3G systems, the WiMAX Forum initiated interim releases for both the system profile and network without major modifications to the IEE 802.16 standard. The work on network release 1.5 network specifications was started in parallel, aimed primarily at enabling dynamic QoS and provisioning of open retail device and support for advanced network services as well as commercial grade VoIP.

The release 1.5 system profile work item was initiated to enable mobile WiMAX in new spectrum including frequency-division duplex (FDD) bands, address a few MAC efficiency improvements needed for technology competitiveness, and align the system profile with advanced network services supported by network release 1.5. All required fixes and minor enhancements needed to support release 1.5 are incorporated in IEEE 802.16 REV2, which combines the IEEE 802.16-2004 base standard plus IEEE 802.16e/f/g amendments and related corrigenda into one specification document.

Following Release 1.5, the next major release mobile WiMAX, Release 2.0, will be based on the next generation of IEEE 802.16, which is being developed in the 16m technical group (TGm) of 802.16. WiMAX Release 2 targets major enhancements in spectrum efficiency, latency, and scalability of the access technology to wider bandwidths in challenging spectrum environments. Currently the expected timeline for the formal completion of 802.16m and WiMAX Certification of Release 2 products are early 2010 and early 2011, respectively.

In parallel with developments in IEEE on the stage 2 system-level description of 802.16m, the requirements for network release 2.0 are being discussed in the WiMAX Forum, where stage 2/3 specifications are expected to be completed by 2010.

Reference: Overview of Mobile WiMAX Technology and Evolution - Kamran Etemad, Intel Corporation

No comments: