Quadrature mirror filter

About: Quadrature mirror filter is a research topic. Over the lifetime, 955 publications have been published within this topic receiving 28900 citations.

Compensation device, and wireless communication device

Abstract: A compensation device for carrying out a compensation process for eliminating image components within a quadrature demodulation signal, the compensation device being provided with a quadrature demodulation compensation unit for compensating for the quadrature demodulation signal having an I signal and a Q signal, wherein the quadrature demodulation compensation unit carries out a compensation process for compensating for the characteristic difference between the frequency characteristic of a first filter carrying out a filter process on the I signal and the frequency characteristic of a second filter carrying out a filter process on the Q signal.

Two-Channel Perfect Reconstruction Filter Banks Using Hilbert Transformers

Abstract: Applying a pi /2 frequency shift to the original twochannel quadrature mirror filter bank (QMFB) yields an equivalent system with two complex half-band filters. Since their coefficients are complex conjugate to each other, one can be removed. The retained filter is a combination of an identity system and a Hilbert transformer, therefore the system is called the quadrature mirror Hilbert transformer (QMHT). However, a perfect reconstruction QMFB is designed by decomposing a zero phase half-band filter into a pair of conjugate mirror filters. The related QMHT is obtained by applying the frequency shift to the zero phase half-band filter before the decomposition. This work establishes the relationship between QMFB and QMHT for systems with perfect reconstruction. For a given QMFB, filter specifications and the design procedure for the QMHT are investigated.

Multirate Signal Processing

Abstract: A frequent task in digital signal processing is to adjust the sampling rate according to the signal of interest. Systems with different sampling rates are referred to as multirate systems. In this chapter, two typical examples will illustrate decimation and interpolation in multirate DSP systems. We will then introduce polyphase notation, and will discuss some efficient decimator designs. At the end of the chapter we will discuss filter banks and a quite new, highly celebrated addition to the DSP toolbox: wavelet analysis.

SDP for multi-criterion QMF bank design

Abstract: The quadrature mirror filter (QMF) bank, with multi-criterion constraints such as minimal aliasing and/or minimal error coding, is among the most important problems in filter bank design, for solving which linear algebra-based methods are still heuristic and do not always work, especially for large filter length. It is shown in this paper that when filters are of nonlinear phase, this problem can be reduced to convex linear matrix inequality (LMI) optimization, which can be very efficiently solved either by the standard LMI solvers or our previously developed solver. The proposed computationally tractable optimization formulations are confirmed by several simulations.