A Review of Physical Layer of Mobile WiMAX System and OFDM

The WiMAX technology, based on the IEEE 802.16-2004 Air Interface Standard israpidly proving itself as a technology that will play a key role in fixed broadband wirelessmetropolitan area networks. The first certification lab, established at Cetecom Labs inMalaga, Spain is fully operational and more than 150 WiMAX trials are underway inEurope, Asia, Africa and North and South America. Unquestionably, Fixed WiMAX, based on the IEEE 802.16-2004 [1] Air Interface Standard, has proven to be a cost-effective fixed wireless alternative to cable and DSL services. In December, 2005 theIEEE ratified the 802.16e amendment [2] to the 802.16 standard. This amendment addsthe features and attributes to the standard necessary to support mobility. The WiMAXForum is now defining system performance and certification profiles based on the IEEE802.16e Mobile Amendment and, going beyond the air interface, the WiMAX Forum isdefining the network architecture necessary for implementing an end-to-end MobileWiMAX2 network. Release-1 system profiles will be completed in early 2006. This particular paper focuesses on giving an overview of the mobile Wimax technology and LDPC coding typically used to enhance the performance of OFDM systems.