Efficient filter design for the global standardized GSM wireless system

Abstract

Implementation of a powerful filter or waveform synthesis invention led to the design of a GSM standardized GMSK baseband processor which has a significantly reduced hardware complexity. A method for designing a filter by storing the possible output waveforms in a look-up table is presented. Based on bit comparisons, the filter controller selects a waveform to output. This method has the advantages of fast design turn-around time and uses very few resources. Using another filter invention, the hardware savings could be as much as 400% which will decrease the power consumption. The design method is applied to a BT/sub b/=0.5 Gaussian low pass filter with several sampling intervals and several quantization levels. In addition, this technique was applied to the Feher (see Wireless Digital Communications: Modulation and Spread Spectrum Applications, New Jersey, Prentice Hall, ch. 4, 1995) filter.