Vertical Handover for 4G Multi-Standard Wireless Transceivers

Future best-connected wireless solutions will involve a multitude of network standards between which the user can switch in order to optimize a set of benefits such as cost and performance. As a result of this convergence, the hardware design of the mobile device will require knowledge about the restrictions imposed by the upper networking layers. This paper starts by presenting the requirements for the connection initialization in the WLAN, WiMAX and 3G standards as they pertain to the mobile transceiver design. It is assumed that the mobile device is based on the dual front-end transceiver architecture where the primary transceiver handles the current network connection while the secondary transceiver (Sniffer) searches for an alternative connection. The paper also presents the handover procedures between these standards that will provide, among other things, the timing requirements for the circuit design.