How does Hiperlan2 compare with 802.11a?
Both specifications operate in the same 5 GHz band, and both use the same OFDM technology. The PHY layers are almost identical. The main differences are at the MAC layer, where the 802.11 MAC – a ‘wireless ethernet’ functionality – was extended to this band from the other 802.11 specifications. In contrast, hiperlan2 chose to support time critical services as well as asynchronous data. Thus packetized voice and video – and the QoS needed to deliver them properly- have been included. This also extends to the defined interfaces on the wired side; Hiperlan2 is compatible with ATM, 3G and 1394 networks as well as IP networks. Hiperlan2 includes transmit power control and dynamic frequency selection in the DLC/RLC layer, which should provide greater spectrum efficiency and lower interference probabilty with other systems operating on 5GHz.
