Comparative Analysis of Orthogonal Frequency Division Modulation and Filter Bank-Based Multicarrier Modulation

Abstract

Multicarrier modulation techniques has been one of the key systems deployed in wired and wireless communication nowadays due to its ability to share communication resources efficiently. Today Orthogonal Frequency Division Multiplexing (OFDM) has been the most implemented multicarrier scheme in recent networks such as Long Term Evolution (LTE) 4G, Digital Video Broadcasting (DVB), Digital Subscriber Line (DSL) and many others. [1]However, with new communication technologies coming up such as 5G, Internet of Things (IoT) and Machine to Machine (M2M), requiring higher bandwidth, greater capacity, security and lower latency. The huge number of users and devices means higher demand for data and network resources; therefore, there is the need for new multicarrier schemes that would be able to meet the requirements of these new technologies, as OFDM is not efficient in circumstances like cognitive radio systems and unsynchronized signals in uplink direction due to its high spectral leakage and bandwidth inefficiency. Filter Bank-based Multicarrier (FBMC) is one of the best contenders that addresses the shortcomings of OFDM and is favourable for the new emerging networks. This study provides a comparative evaluation of OFDM with Cyclic Prefix (CP) and FBMC with Offset Quadrature Amplitude Modulation (OQAM) processing [1]. The two techniques were compared using analytical expressions and simulations over MATLAB. Parameters such as power spectral density, subcarriers waveforms, prototype filters, computational complexity, delay and spectral efficiency were compared. Results of the analysis have proven that FBMC outperforms OFDM as it offers better bandwidth efficiency and spectral localization in time and frequency with low out-of-band leakage, making it more appropriate for the all-new upcoming technologies.