Novel control for delay-locked loop in IR-UWB communication systems

• Derive a novel structure of DLL tracking system, using IMC approach.
• Improve the structure of the proposed DLL, taking linear Doppler effect into account.
• Modify the IMC tracking structure, by adding two blocks: classifier and MA filter.
• Study the system for different values of the threshold dmax and the average rank.
• Compare tracking performance between the classical and proposed DLL methods.

Timing synchronization represents a major challenge in carrying out highly efficient ultra-wideband (UWB) communications. The delay-locked loop (DLL) method is widely proposed to maintain the satisfactory synchronization and reduce timing error. In this paper, the structure of DLL is modified by using the internal model control (IMC). This novel approach in the telecommunication systems has a good performance of overcoming disturbance and deviations of model parameters. Then the proposed IMC-DLL structure is developed, and by taking a linear Doppler Effect into account. This development is achieved by using the following two approaches: multi-model approach and moving average filter. Finally, the simulation results confirm that the proposed IMC-DLL system is able to achieve satisfactory and accurate tracking even in the presence of Doppler effect, and they also confirm that the proposed DLL has higher transient response, compared with the classical one.