Characterization of BandPass Delta Sigma Modulators in Wireless Transceivers Using Parameter Identification

In this paper, a method to study and characterize a single-loop, cascaded and 1-bit Band-Pass Delta Sigma modulator for digital transmitter is presented. This technique is based on a combination of digital filter simulation and nonlinear optimization of signal-to-quantization noise. The optimal coefficients of modulator structure are achieved by minimization of a quadratic criterion based on prediction error between desired digital filter and noise transfer model. To demonstrate the effectiveness of this approach, simulated results for a sixth order cascaded structure for WCDMA Band-1 standard are presented. Spurious and ACLR improvement could be achieved for this standard with the proposed characterization technique.