Spectrum co-existence of IEEE 802.11b and 802.16a networks using reactive and proactive etiquette policies." (Journal Article

Abstract This paper presents an investigation of spectrum co-existence between IEEE 802.11b and 802.16a networks in the same shared frequency band using cognitive radio techniques with different levels of complexity. Simple re-active interference avoidance algorithms as well as proac-tive spectrum coordination policies based on etiquette pro-tocols are proposed and compared in terms of achievable spectrum efficiency in a shared Wi-Fi/Wi-Max scenario. In reactive interference avoidance methods, radio nodes coor-dinate spectrum usage without exchange of explicit control information—this is done by adaptively adjusting transmit PHY parameters such as frequency, power and time occu-pancy based on local observations of the radio band. Because local observations provide information only about transmit-ters, they may not be sufficient for resolving spectrum con-tention in scenarios with “hidden receivers”. Proactive co-ordination techniques solve the hidden-receiver problem by utilizing a common spectrum coordination channel (CSCC) for exchange of transmitter and receiver parameters. Radio nodes can cooperatively select key PHY-layer variables such as frequency and power by broadcasting messages in the CSCC channel and then following specified spectrum eti