Open-ended waveguide antenna for microwave breast cancer detection

Microwave imaging techniques for breast cancer detection have attacked many research groups recently. The key element for the microwave imaging system is the antenna. In this paper, a small flanged open-ended rectangular waveguide antenna (ORWA) is proposed for breast cancer detection. WR 62 waveguide which has cut-off frequency of 9.5 GHz is used in the design process. A 16-element antenna array plane is proposed for operation at a frequency of 12.6 GHz. Measurement and simulation results show that the designed single ORWA can obtain a return loss less than -60 dB at frequency of 12.12 GHz. The scattered field detection capability is also tested under our developed holographic microwave imaging array (HMIA) system for breast phantom detection. The experimental results show that the proposed ORWA has the ability to detect tumour as small as 2.5 mm within the breast phantom.