Multi-rate Polyphase DSP and LMS Calibration Schemes for Oversampled ADCs

作者：Gupta Subhanshu^*; Tang Yi; Paramesh Jeyanandh; Allstot David J

来源：Journal of Signal Processing Systems for Signal Image and Video Technology, 2012, 69(3): 329-338.

DOI：10.1007/s11265-012-0677-3

• Multi-rate
• Adaptive LMS
• Decimation
• Polyphase decimation
• Noble identities
• Sigma-delta
• Delta-sigma
• Oversampled ADC
• Fixed-point multi-rate implementation
• Low-gain opamp
• Calibration accuracy

A scaling-friendly approach for the low-power calibration of oversampled analog-to-digital (A/D) systems is presented. A 22-dB amplifier relaxes the design constraints of the analog front-end (AFE). The integrator non-idealities in the AFE of the sigma-delta (I I") pound ADC are calibrated using a multi-rate polyphase least-mean squares (LMS) algorithm. The proposed half- (f (s)/2) and quarter-rate (f (s)/4) LMS calibration schemes reduce computational complexity and achieve more than 2.5x savings in digital power consumption for low-OSR (over-sampling ratio) Delta I pound ADCs, which require higher adaptive filter orders and sampling frequencies. The proposed scheme can have further applications in serial-link I/O and sub-band echo cancellation architectures.

• 出版日期2012-12