<P> WiMAX Release 2 provided backward compatibility with Release 1 . WiMAX operators could migrate from release 1 to release 2 by upgrading channel cards or software . The WiMAX 2 Collaboration Initiative was formed to help this transition . </P> <P> It was anticipated that using 4X2 MIMO in the urban microcell scenario with only a single 20 MHz TDD channel available system wide, the 802.16 m system can support both 120 Mbit / s downlink and 60 Mbit / s uplink per site simultaneously . It was expected that the WiMAX Release 2 would be available commercially in the 2011--2012 timeframe . </P> <P> A field test conducted in 2007 by SUIRG (Satellite Users Interference Reduction Group) with support from the U.S. Navy, the Global VSAT Forum, and several member organizations yielded results showing interference at 12 km when using the same channels for both the WiMAX systems and satellites in C - band . </P> <Table> <Tr> <Td> </Td> <Td> This section needs to be updated . Please update this article to reflect recent events or newly available information . (November 2015) </Td> </Tr> </Table>

Discuss wimax (802.16) with protocol architecture and their services