alderbank, R. (2017). Orthogonal time frequency space modulation. IEEE WCNC, IEEE, pp. 1-6. 4 Generalized Frequency Division Multiplexing: Unified Multicarrier Framework 24 Nimr, A., Chafii, M., Matthe, M., and Fettweis, G.P. (2018). Extended GFDM frame- work: OTFS and GFDM comparison. GLOBECOM, IEEE, pp. 1-6. 25 Nimr, A., Zhang, D., Martinez, A.B., and Fettweis, G.P. (2017). A study on the physical layer performance of GFDM for high throughput wireless communication. EUSIPCO, IEEE, pp. 638-642. Filter Bank Multicarrier Modulation Behrouz Farhang-Boroujeny Electrical and Computer Engineering Department, University of Utah, USA Introduction Despite the dominance of orthogonal frequency division multiplexing (OFDM) as the most popular broadband communications technology in both wired [1] and wireless [2] applica- tions, there still exist use cases where other alternatives may suit better. For instance, OFDM may degrade significantly in channels with fast variation in time; see Chapter 6 for more explanation and a solution. Another situation where OFDM degradation may be noticeable is in channels with partial band interference. Poor response of the OFDM prototype filter makes suppression of such interference a difficult task. Although some filtering methods have been proposed to overcome this problem (see Chapter 2 these are somewhat lim- ited in performance. The filter bank multicarrier (FBMC) techniques that are presented in this chapter provide a perfect solution to partial band interference, simply by deactivating the interfered subcarrier bands. Moreover, as discussed in Section 5.4, the FBMC proto- type filter can be designed to balance its robustness to both time spreading (i.e. frequency selectivity) and frequency spreading (i.e. variation in time) of the channel. This chapter is organized as follows. A summary of FBMC methods is discussed in Section 5.2. The fundamental theory behind the class of FBMC systems that achieve maxi- mum compactness both in time and frequency is presented in Section 5.3. The subj