This paper defines the requirements for cooperation of heterogeneous radio

access networks (RANs) and proposes a novel radio resource management (RRM) framework

for support of mobility and quality of service (QoS) in a heterogeneous communication

environment comprising IMT-Advanced and legacy systems. The reference IMT-Advanced

system is the one developed within the IST projectWINNER(IST-2003-507581 ProjectWireless

Initiative New Radio, http://www.ist-winner.org). The RRM mechanisms are evolved

from traditional ones to comply with the requirements imposed by a simplified new (RAN)

architecture as proposed for IMT-Advanced systems. The RRM mechanisms are evaluated

for the scenario of intra-RAN and inter-RAN user mobility. The RRM framework incorporates

as novelty improved triggering mechanisms, a network-controlledmobility management

scheme with policy enforcement on different levels in the RANarchitecture, and a distributed