HIPERLAN system performance under DCA and FCA

HIPERLAN is a high speed wireless LAN standard adopted by the ETSI. It operates in 150 MHz of spectrum in the 5 GHz band, with up to five TDD channels provided for duplex data transmission at up to 23.5 Mb/s. This paper shows that in the presence of cochannel cells and full link utilisation, HIPERLAN performs poorly when using its DCA-type clear channel assessment (CCA) scheme, and that the target performance levels are only achievable under optimal FCA-type channel assignments. Two main factors contribute to this poor performance: HIPERLAN has insufficient channels to meet C/I constraints in the presence of cochannel cells; and the CCA scheme results in poor channel distributions.