Dynamic channel allocation (DCA) is a wide definition for functionality that aims to optimise the usage of radio resources by applying intelligence to the channel selection process.DCA schemes can be based on many different variables and different applications provide varying degrees of freedom in the channel selection. The DCA schemes are commonly categorised as traffic adaptive (TA-DCA) or interference adaptive(IA-DCA).
This chapter presents a dynamic channel allocation scheme called dynamic frequency and channel allocation (DFCA1). DFCA is a centralised IA-DCA scheme based on the estimation of carrier to interference ratio (CIR) on possible channels. The aim is to optimise the distribution of interference taking into account the unique channel quality requirements of different users and services. DFCA utilises cyclic frequency hopping for
maximum frequency diversity gain. With adequate base transceiver station (BTS) support DFCA can freely choose the mobile allocation (MA) list, mobile allocation index offset (MAIO), timeslot (TSL) and the training sequence code (TSC) that will be used for each connection regardless of the physical transceiver. The basic requirement for DFCA is that the air interface is synchronised, as synchronisation provides timeslot alignment and time division multiple access (TDMA) frame number control, which are needed for timeslot level CIR estimation with cyclic frequency hopping.
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