Detección de parámetros y sincronización de OFDM sobre GNU Radio en sistemas multimodo

Abstract

An Orthogonal Frequency-Division Multiplexing (OFDM) system may have different operation modes, each one with its own symbol and cyclic prefix lengths. In many cases, the receiver needs to detect the operation mode based solely on the received OFDM signal, besides performing symbol and frame synchronization. An algorithm based on the detection of the cyclic prefix to identify the operation mode and perform symbol synchronization has been implemented with software radio. In addition, we suggest an algorithm for frame synchronization. Simulations are used to evaluate the performance of the system in the presence of white noise. Results show that the algorithm perform well, even in low-SNR scenarios. An improvement to the mode detection algorithm is also proposed and evaluated.