An adaptive synchronization scheme for 60 GHz subsampling receivers

This paper presents an adaptive method for symbol synchronization in a WiGig subsampling receiver targeting low power applications, such as high data-rate communications in mobile devices. Taking advantage of the configurability of the receiver, the proposed implementation can achieve symbol synchronization in less than 2.5 μs, relative to the data frequency f_data = 1.76 GHz. A fast detection algorithm is introduced in order to reduce convergence time by a factor between 4 and 40. The convergence is achieved when finding the correct sampling instant corresponding to the beginning of a new symbol and the delay between in-phase I and quadrature-phase Q paths. These 2 parameters have been identified to have the highest impact on the performances of the receiver. It is shown that the proposed method is totally independent of the process and temperature variations and can achieve synchronization even if there is no calibration process for the cells used in the circuit.