IEEE 802.11n is a newly emerging WLAN standard capable of providing dramatically increased throughput as well as improved range, reduced signal fading, over the existing 802.11a/g WLAN standards. These benefits achieved from the use of MIMO (Multiple Input Multiple Output). The latest draft for IEEE 802.11n describes rates up to 600 Mbps, exceeding the rate than that of 11a/g standard by more than ten times. In addition, techniques such as space-time block coding provide the potential of increasing signal strength at the receiver with optimal efficiency, based on the diversity order used.
In this paper, a comparative analysis of the physical (PHY) layer in the original main proposals for the 11n amendment is presented. The key architectural differences governing the performance of this proposal using or without using space coding technique is outlined. In this paper, performance curves (based on simulation models developed on MATLAB/SIMULINK) are used to verify the analysis presented. This paper also includes a discussion of some of the future challenges for the 11n amendment. A space–time code (STC) is a method employed to improve the reliability of data in using multiple transmit. STCs rely on transmitting multiple, copies of a data stream to the in the hope that at least some of them may survive the between transmission and reception in a good enough state to allow reliable decoding.