Analysis and Design of FIR Filter applied to F-OFDM Technology
Abstract
A candidate technology to be used in the new generation of mobile communication, the 5G, is the F-OFDM (Filtered-Orthogonal Frequency Division Multiplexing) modulation, which basically consists of the application of filters in the OFDM modulation subbands. Techniques such as windowing allow the design of FIR (Finite Impulse Response) filters with variable performance depending on the chosen window, but which generally provides greater efficiency in the transmission and reception of data signals when compared to the OFDM modulation. In this article different types of windows are analyzed for the FIR filter design to be used in F-OFDM. In addition, this article proposes the use of pulse shaping techniques to design the FIR filter prototype in order to increase its performance. In order to evaluate the proposal of the article, simulations of image transmission using F-OFDM modulation are carried out in comparison to OFDM modulation in terms of BER (Bit Error Rate). The results obtained in the simulations indicate that the performance of F-OFDM is generally higher than that obtained with OFDM modulation, but variable according to the filter design. In simulations, reduced BER values were obtained using the proposed filter: an application of the pulse shaping technique to the FIR filter prototype combined to the appropriate choice of the window to be used in the filter. The results indicate the relevance of the F-OFDM modulation filter design to make F-OFDM a modulation candidate to be used in new data communications architectures, including 5G.
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