نوع مقاله : مقاله پژوهشی
عنوان مقاله English
نویسنده English
In this paper, a FF, three-order, 3-bit continuous time quadrature delta-sigma modulator by applying error-feedback method is designed for a wideband radar receiver. In this method, the quantization noise of the modulator is extracted then injected to the output of the loop filter by a transfer function consist of delays in the z domain. The proposed method adds a zero to the modulator’s NTF that increases the modulator’s order without adding active blocks. The first, the primary NTF zeros are located at the pass band, and then applying the error-feedback method adds a zero in DC, which increases the bandwidth and SNR of the modulator. Bandwidth, center frequency and SNR of conventional modulator are 0.03Fs, 0.029Fs and 76.48dB, respectively then for proposed structure are 0.044Fs and 0.0215Fs and 86.52dB, respectively. Comparison of the results shows that the bandwidth and SNR of the proposed structure increased by more than 30 and 10 percent, respectively, compared with the conventional structure.
کلیدواژهها English
