ROPAS: Cross-layer Cognitive Architecture for Mobile UWB Networks

The allocation of channel bandwidth without significantly increasing the interference among existing users is a challenge for the future UWB networks. Our research work presents a novel rake optimization and power aware scheduling (ROPAS) architecture for UWB networks. We propose to use cognitive radio (CR) for dynamic channel allocation among the requesting users while limiting the average power transmitted in each sub-band. In our proposed ROPAS architecture, dynamic channel allocation is achieved by a CR-based cross-layer design between the PHY and medium access control (MAC) layers. The joint power control and link scheduling in the MAC layer reduces adjacent channel and multi-access interference introduced by multiple access of the links. Furthermore, the Rake optimization with its strategic selection of propagation paths achieves the minimal bit-error rate (BER) at the rake receiver by mixed integer programming. Our simulated-based performance evaluation confirms the effectiveness and novelty of our proposed ROPAS architecture.