Compact and Low‐Cost Ultrawideband Breast Tumor Microwave Detection System Based on an Equivalent Sampling Receiver

ABSTRACT A microwave detection system based on an equivalent sampling receiver is proposed to detect breast tumors, aiming to develop a portable, compact, and low‐cost solution. The system comprises an ultrawideband (UWB) pulse generator, breast phantoms, an antenna array, and the proposed receiver, which has a maximum input bandwidth of 18 GHz with a minimum clock step of 10 ps. The pulse generator outputs a monocycle pulse with a bandwidth of 0.50–5.25 GHz. The breast phantoms include square and realistic breast models, with soybean oil as the fat medium. The antenna array is uniformly distributed around the breast phantom, sequentially transmitting pulse signals, and receives scattered signals. The receiver captures these signals and transmits them to a personal computer (PC) for data processing and image reconstruction. Measurements are taken with different types, sizes, and depths of tumor phantoms in breast models. A 5‐mm bacon target is successfully detected, with a relative error and coordinate error of 2.19% and 2.83 mm, respectively. The signal‐to‐clutter ratio (SCR) and signal‐to‐mean ratio (SMR) are 2.90 and 8.35 dB, respectively. It demonstrates that the designed UWB microwave detection system can identify small‐sized breast tumor targets and has the potential to replace large commercial and expensive instruments, enabling miniaturization and portability.