Abstract: There is provided a multi-mode communication system which is operable according to different operating modes, such as GSM and WCDMA. The multi-mode communication system includes first and second switching units, a delta-sigma modulator, an analog-to-digital converter, sequential convolution units and a selection unit. The delta-sigma modulator samples an analog signal, which is inputted through the first switching unit in one mode, into 1-bit digital signal. In another mode, the analog-to-digital converter samples an analog signal, which is inputted through the first switching unit into an n-bit digital signal. The sequential convolution units multiply filter factors with the output of the delta-sigma modulator, which is inputted through the second switching unit at the first mode, and multiply PN codes by the output of the analog-to-digital converter, which is inputted through the second switching unit at the second mode, to generate WCDMA output waveforms.

Abstract: There is provided a multi-mode communication system which is operable according to different operating modes, such as GSM and WCDMA. The multi-mode communication system includes first and second switching units, a delta-sigma modulator, an analog-to-digital converter, sequential convolution units and a selection unit. The delta-sigma modulator samples an analog signal, which is inputted through the first switching unit in one mode, into 1-bit digital signal. In another mode, the analog-to-digital converter samples an analog signal, which is inputted through the first switching unit into an n-bit digital signal. The sequential convolution units multiply filter factors with the output of the delta-sigma modulator, which is inputted through the second switching unit at the first mode, and multiply PN codes by the output of the analog-to-digital converter, which is inputted through the second switching unit at the second mode, to generate WCDMA output waveforms.