Title :
Programmable modified fractional comb decimation filter
Author :
Babic, Djordje ; Renfors, Markku
Author_Institution :
Inst. of Commun. Eng., Tampere Univ. of Technol., Tampere, Finland
Abstract :
In multistandard radio receivers, the hardware should be configurable or programmable for the reception of different types of signals having different symbol rates. The decimation by a non-integer factor becomes a critical functionality of the multistandard radio. The Cascaded Integrator-Comb (CIC) filters are commonly used for decimation by an integer. By using polynomial interpolation filter between integrator and comb stages of CIC, and non-integer delay in the feed-forward branch of the comb stage, we achieve improved attenuation for the aliasing frequency components, and we make possible to use this type of structure for decimation by a non-integer factor. We name this structure as a programmable fractional CIC filter structure. This paper presents an efficient fractional structure for flexible decimation in the multistandard radio receivers. This structure is based on the so-called modified comb filter using the programmable fractional CIC principle. The main advantages of the proposed structure are flexibility and programmability with increased attenuation for aliasing frequency components.
Keywords :
comb filters; radio receivers; cascaded integrator-comb filter; fractional structure; frequency component aliasing; multistandard radio receivers; noninteger delay; noninteger factor; polynomial interpolation filter; programmable fractional CIC filter structure; programmable modified fractional comb decimation filter; symbol rates; Abstracts;
Conference_Titel :
Signal Processing Conference, 2002 11th European
Conference_Location :
Toulouse