Among the physical layers, .11, .11b, .11a, .11g and Draft n offer progressive speeds over the course of development, which are as follows
|Standard||Year||Modulation||Peak Rate||Peak Throughput|
|.11||1999||DSSS||2 Mbps||1 Mbps|
|.11b||1999||CCK||11 Mbps||6 Mbps|
|.11a||1999||OFDM||54 Mbps||25 Mbps|
|.11g||2003||OFDM||54 Mbps||22 Mbps|
|Draft n||2006||MIMO OFDM||300 Mbps||180 Mbps|
Also available are security features vital to wireless protection; QoS support that improves the service quality when service compromise becomes inevitable; radar detection that avoids interference with airport or weather Radar operations.
Users should evaluate application needs carefully and tailor the product appropriately. A sample of video application requirements are listed as follows:
|Cable Modem||6 Mbps|
|HD DVD||36 Mbps|
|Blue-ray DVD||48 Mbps|
Video streaming is very demanding in frame errors, e.g., FER < 10-4 or tighter, so the peak throughput of a specific WLAN device is recommended to scale down to one-third of its original value for budgetary purposes. For example, a peak throughput of 15 Mbps is necessary for satisfactory SDTV streaming at 5 Mbps in general.
Ralink offers a full array of WLAN products including the latest Draft-n chipset. Peak throughput exceeds 180 Mbps in lab tests, which meets all of the above video application requirements with ease.