Controlling desired frequency without affecting physical size of wideband microstrip antenna is a challenging issue especially for breast cancer microwave imaging application. This paper presents a solution for improving the lower frequency operation and achieving wider frequency bandwidth by introducing Conductor Backed Coplanar Waveguide (CBCPW) feeding and adopting stubline with notch-staircase shape on radiating patch design.

The dimension of the proposed design is 43 × 43 × 1.6 mm³ which reducing 23% in size compared to the antenna without CBCPW feeding. The antenna operates from 1.85 to 8.37 GHz with 127.6% of fractional bandwidth. It showed a good reflection coefficient with mostly below −15 dB and gain varies from 1 dBi to 5.27 dBi across the impedance bandwidth. The proposed antenna is also experimentally verified, achieving acceptable agreement between the simulation and measurement results. In addition, time domain performance such as input and received signal response and group delay are also observed for the proposed antenna. Owing to its compact size, wideband frequency operation and other acceptable performance, the proposed antenna is suitable for breast tumor imaging implementation.

在不影响宽带微带天线的物理尺寸的情况下控制所需的频率是一个具有挑战性的问题，特别是对于乳腺癌微波成像应用而言。本文提出了一种解决方案，通过引入背衬导体共面波导（CBCPW）馈电并在辐射贴片设计中采用带缺口阶梯形状的短线来改善低频工作并实现更大的带宽。

拟议设计的尺寸为43×43×1.6 mm ³，与不带CBCPW馈电的天线相比，其尺寸减小了23％。该天线的工作频率为1.85至8.37 GHz，具有部分带宽的127.6％。它显示出良好的反射系数，大多数情况下低于-15 dB，并且整个阻抗带宽的增益在1 dBi至5.27 dBi之间变化。提出的天线也经过实验验证，在仿真和测量结果之间达成了可接受的一致性。另外，对于所提出的天线，还观察到时域性能，例如输入和接收信号响应以及群延迟。由于其紧凑的尺寸，宽带频率操作和其他可接受的性能，因此所提出的天线适用于乳腺肿瘤成像。