High Speed Downlink Packet Access (HSDPA) is an enhancement to the first UMTS (WCDMA) release (Release 99) to be deployed, in order to get to data rates up to 14.4Mbps on the downlink. HSDPA is based on channel allocation to a particular user according to the current radio conditions. However, the gains in data rates come at the cost of implementation challenges such as more complex front-end algorithms and tighter latency constraints on modem processing. In this paper, we discuss the impact of these implementation challenges on designing next generation WCDMA handset modems.