Time-varying cosine-modulated filter banks

In this work, we have generally studied time-varying cosine-modulated filter banks. The general PR conditions for an LTV cosine-modulated filter bank are given. Applying the theory in analyzing a special time-varying cosine-modulated filter bank, namely time-varying modulated lapped transforms (LTV MLTs), we have provided a solid theoretical support for the well-known window-switching techniques.