Safety assessment of breast cancer detection via ultrawideband microwave radar operating in swept-frequency mode

Ultrawideband (UWB) microwave radar is a promising modality for detecting early-stage breast cancer. In our current prototype, we synthesize an antenna array by scanning a single antenna to each array position and sequentially transmitting a swept-frequency signal and receiving the backscatter. Our UWB radar operates in the 1-11 GHz frequency band. While it has been assumed that low-power UWB microwave breast cancer detection technology poses no health risk, it is important to formally evaluate the absorption of electromagnetic energy in the breast to establish the safety of such exposure prior to clinical implementation. In this paper, we report the results of finite-difference time-domain (FDTD) investigations of the specific absorption rate (SAR) in 3-D numerical breast models due to microwave radiation in the 1-11 GHz frequency band