# A Sparse Denoising-Based Super-Resolution Method for Scanning Radar Imaging

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## Abstract

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## 1. Introduction

- We point out that the azimuth echo of a scanning radar can be regarded as a convolution of the antenna pattern and target scattering distribution, so the azimuth resolution of scanning radar can be improved via deconvolution methods.
- To improve on the shortcomings of traditional SSM, we propose the SDBSM method to improve the azimuth resolution of a scanning radar. The proposed SDBSM uses the sparsity constraint of the target to denoise, and it realizes the scanning radar super-resolution imaging through the cross-iteration of denoising and deconvolution.
- We compare SDBSM with traditional TSVDM, FTVM, MLE, IAA, MAPE and SSM using simulations and real data. This demonstrates that SDBSM can effectively preserve the shape of a main target while resolving the adjacent targets, which is helpful for identifying the main target.

## 2. Super-Resolution Imaging Using Traditional SSM

## 3. Super-Resolution Imaging Using the Proposed SDBSM

#### 3.1. Deduction of the Method

#### 3.2. Analysis of the Computational Complexity

## 4. Experimental Verification of the Proposed SDBSM

#### 4.1. A Simulation of Strong-Point Targets

#### 4.2. Simulations of Area Targets

#### 4.3. Real Data Verification

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## Appendix A. Pseudocode of the Proposed SDBSM

## References

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**Figure 2.**Point targets simulation results with the SNR of $20\mathrm{dB}$. (

**a**) Real-aperture echo. (

**b**) Result processed by TSVDM. (

**c**) Result processed by FTVM. (

**d**) Result processed by MLE. (

**e**) Result processed by IAA. (

**f**) Result processed by MAPE. (

**g**) Result processed by SSM. (

**h**) Result processed by SDBSM.

**Figure 3.**Point targets simulation results with the SNR of $10\mathrm{dB}$. (

**a**) Real-aperture echo. (

**b**) Result processed by TSVDM. (

**c**) Result processed by FTVM. (

**d**) Result processed by MLE. (

**e**) Result processed by IAA. (

**f**) Result processed by MAPE. (

**g**) Result processed by SSM. (

**h**) Result processed by SDBSM.

**Figure 5.**Area targets simulation results with the SNR of 20 dB. (

**a**) Real-aperture echo. (

**b**) Result processed by TSVDM. (

**c**) Result processed by FTVM. (

**d**) Result processed by MLE. (

**e**) Result processed by IAA. (

**f**) Result processed by MAPE. (

**g**) Result processed by SSM. (

**h**) Result processed by SDBSM.

**Figure 6.**Area targets simulation results with the SNR of 10 dB. (

**a**) Real-aperture echo. (

**b**) Result processed by TSVDM. (

**c**) Result processed by FTVM. (

**d**) Result processed by MLE. (

**e**) Result processed by IAA. (

**f**) Result processed by MAPE. (

**g**) Result processed by SSM. (

**h**) Result processed by SDBSM.

**Figure 7.**Super-resolution results of real data. (

**a**) Optical scenario. (

**b**) Real-aperture echo. (

**c**) Result processed by TSVDM. (

**d**) Result processed by FTVM. (

**e**) Result processed by MLE. (

**f**) Result processed by IAA. (

**g**) Result processed by MAPE. (

**h**) Result processed by SSM. (

**i**) Result processed by SDBSM.

Methods | BSR | |
---|---|---|

High SNR | Low SNR | |

IAA | 4.06 | None |

MAPE | 13.3 | 6.66 |

SSM | 12.0 | 9.6 |

SDBSM | 8.27 | 5.33 |

Methods | Entropy | |
---|---|---|

High SNR | Low SNR | |

Echo | 5.45 | 5.49 |

TSVDM | 5.61 | 5.74 |

TVM | 5.43 | 6.01 |

MLE | 3.34 | 3.65 |

IAA | 4.03 | 4.74 |

MAPE | 1.98 | 2.87 |

SSM | 2.72 | 2.78 |

SDBSM | 1.53 | 2.53 |

Parameter | Value |
---|---|

Beam width of the antenna | 4${}^{\circ}$ |

Carrier frequency | 30.75 GHz |

Band width of the transmitted signal | 200 MHz |

Antenna scanning speed | 60${}^{\circ}$/s |

Scanning region | ±30${}^{\circ}$ |

PRF | 500 Hz |

Methods | Echo | TSVDM | FTVM | MLE | IAA | MAPE | SSM | SDBSM |
---|---|---|---|---|---|---|---|---|

Entropy | 4.84 | 4.65 | 4.65 | 4.71 | 4.75 | 4.54 | 4.51 | 4.34 |

Contrast | 5.89 | 6.01 | 7.69 | 7.46 | 9.21 | 9.38 | 10.95 | 12.21 |

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**MDPI and ACS Style**

Zhang, Q.; Zhang, Y.; Zhang, Y.; Huang, Y.; Yang, J.
A Sparse Denoising-Based Super-Resolution Method for Scanning Radar Imaging. *Remote Sens.* **2021**, *13*, 2768.
https://doi.org/10.3390/rs13142768

**AMA Style**

Zhang Q, Zhang Y, Zhang Y, Huang Y, Yang J.
A Sparse Denoising-Based Super-Resolution Method for Scanning Radar Imaging. *Remote Sensing*. 2021; 13(14):2768.
https://doi.org/10.3390/rs13142768

**Chicago/Turabian Style**

Zhang, Qiping, Yin Zhang, Yongchao Zhang, Yulin Huang, and Jianyu Yang.
2021. "A Sparse Denoising-Based Super-Resolution Method for Scanning Radar Imaging" *Remote Sensing* 13, no. 14: 2768.
https://doi.org/10.3390/rs13142768