# Automatic Calibration Method of Channel Mismatches for Wideband TI-ADC System

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Calibration Method

#### 2.1. Estimation Method Based on Three-Parameter Least-Squares Fit to Sine-Wave Data

_{0}to ADC

_{M}

_{−1}is $2\pi /M$ in sequence. The frequency range of sampled signal is $(0,{f}_{S}/2)$. Sine sequence of $K$ frequency points ${f}_{1},{f}_{2},\cdots ,{f}_{K}$ is acquired at equal frequency intervals in $(0,{f}_{S}/2)$. Using the above sinusoidal three-parameter fitting estimation method, the amplitude discrete function ${A}_{m}({f}_{k})$ and the phase discrete function ${\varphi}_{m}({f}_{k})$ of each channel at $K$ frequency points are obtained, where $m=0,1,\cdots ,M-1$ and $k=1,2,\cdots ,K$.

#### 2.2. Compensation Method Based on Perfect Reconstruction

## 3. System Architecture

## 4. Results and Discussion

## 5. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

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**Figure 1.**The ideal model of an M-channel TI-ADC (Time-interleaved analog-to-digital converter) system.

**Figure 7.**The spectrum of 2.81 GHz sinusoidal signal: (

**a**) before calibration; (

**b**) after calibration.

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**MDPI and ACS Style**

Li, J.; Pan, J.; Zhang, Y. Automatic Calibration Method of Channel Mismatches for Wideband TI-ADC System. *Electronics* **2019**, *8*, 56.
https://doi.org/10.3390/electronics8010056

**AMA Style**

Li J, Pan J, Zhang Y. Automatic Calibration Method of Channel Mismatches for Wideband TI-ADC System. *Electronics*. 2019; 8(1):56.
https://doi.org/10.3390/electronics8010056

**Chicago/Turabian Style**

Li, Jingyu, Jiameng Pan, and Yue Zhang. 2019. "Automatic Calibration Method of Channel Mismatches for Wideband TI-ADC System" *Electronics* 8, no. 1: 56.
https://doi.org/10.3390/electronics8010056