5 5 月, 2026 Uncategorized

CST毫米波雷達模擬解決方案介紹(六)

本期我們繼續介紹天線和饋電網路整合在一起的最佳化設計。

  1. 先把優化好的3D饋電網路和天線陣列放在同一個CST工程裡面,饋電網路的各個輸出埠朝向陣列天線的各個單元的饋電口。在饋電網路和天線之間預留一定空間,方便後續的走線。
CST Studio Suite 3D simulation model of a series-fed patch antenna array for mmWave radar applications.
Corporate feeding network design and power divider structure for a mmWave radar antenna array in CST.

2. 接下來需要把饋電網路和天線陣子整合在一起。在創建饋電網路到天線單元饋電口之間的走線時,我們可以透過參數化的curve來實現,以curve的長度作為後續的最佳化變數。下圖可看出curve長度變化對走線的影響。

Detailed view of meander line phase shifters in the antenna feeding network using CST Studio Suite.
Animating parameter variations for curved feed lengths in CST to optimize mmWave radar antenna geometry.

3. 完成3D建模之後,開啟CST的Optimizer,在最佳化變數中選擇array_sapcing、curved_deedlength以及其他饋電網路相關的變數。最佳化目標裡設定S11、SLL和3dB頻寬等目標值。

CST Optimizer settings using the Trust Region Framework algorithm to define parameter boundaries for antenna design.
Defining CST optimization goals including S11 parameters, realized gain, and side lobe levels for radar antenna performance.

4. 點選start之後,CST快速地得到了最佳化後結果,我們可以看到S11還沒有達到目標值。

S-parameter (S11) magnitude plot for a 77 GHz mmWave radar antenna, showing a deep resonance dip at 77.013 GHz in CST Studio Suite.

5. 在饋電網路和天線整合在一起後,仍然可以在饋電網路的輸入埠處以開路短截線對整個天線系統的阻抗進行匹配最佳化。

Antenna geometry tuning in CST demonstrating how modifying specific feedline dimensions affects the S11 parameter resonance for 77 GHz radar design.

6. 透過3D遠場結果,可以直觀地查看天線遠場性能。

Comparison of 3D farfield directivity patterns at 76 GHz, 77 GHz, and 78 GHz for a mmWave radar array, simulated in CST Studio Suite.

7. 接下來我們在3D模型中再加上天線罩及汽車bumper,評估其對天線S參數及遠場性能的影響。

3D farfield gain pattern of a complete mmWave radar antenna array with radome, showing a peak gain of 19.74 dBi at 77 GHz.

8. 確保天線性能符合要求之後,將進入下一步:雷達天線安裝評估。

2D polar plot of farfield absolute gain at Phi=0 (elevation plane) for a 77 GHz radar antenna, analyzing main lobe magnitude and side lobe levels.
2D polar plot of farfield absolute gain at Phi=90 (azimuth plane) for a 77 GHz radar antenna, evaluating angular width and radiation performance.

本文轉載來自:CST毫米波雷达仿真解决方案介绍(六)