Abstract:

The frequency response masking (FRM) technology is widely used in digital channelized and related fields because of advantages of the filter design with narrow transition band. An improved structure of even arrangement channelized based on FRM was proposed according to the problem of high complexity brought by design of narrow transition band channelized. The prototype filter of the improved structure was designed by half-band filter, and also two masking filters are designed by the same low pass filter through modulation. The sub-band signals of each channel are synthesized as the output signal with upper and lower arms. The improved structure is derived from the condition of non-maximally decimated based on FRM, and the computational complexity of the structure is less than the conventional structure. The improved channelized structure has the extensive applicability without the limit of higher sampling rate due to the decimation module placed at the forefront of channelized. Simulations show that the improved structure is correct and can save 67.9% multipliers compared with polyphase structure under the conditions of 16-channels example.

Key words: frequency response masking, prototype filter, even-arrangement, masking filters, non-maximally decimated