Adaptive time mismatches identification and correction in polar transmitter architecture

This paper deals with synchronization in EER type of transmitter architecture, illustrated in the context of 3GPP standard. Firstly, we point out the sensitivity of such architecture to delay mismatch between the two signals path. This sensitivity can be observed on EVM and output spectrum performances. To correct this default, two algorithms are studied. Both are based on the comparison between the emitted signal and the digitally generated one but with the difference that the first algorithm needs I/Q demodulation whereas the second one only needs the in-phase component of the transmitted signal. We demonstrate that the quality of the interpolator used is crucial. Implementation details are given. We present simulation results realised with HPADS and draw attention to the enhancement of the transmitter performances using such algorithm.