Microwave Medical Imaging
Mohammad Amin Arbabian and Ali Niknejad
Cancer is the second leading cause of death in the U.S. and the world. Detection in early stages has proven to be essential for reducing the mortality rate. Medical imaging techniques are used to detect and classify potential cancerous tissues by the "traces" that are left from the abnormal cells. Depending on the imaging modality, tumor biology, and the physical parameters involved in the system, the effectiveness of the provided visualization for the process of detection is examined.
The focus of this research is to use the contrast in microwave signals to various tissue abnormalities for the early detection of cancer. In order to achieve this, a large bandwidth is required to provide adequate lateral resolution. UWB signaling provides greater frequency information as well as sufficient tissue penetration, but requires a careful design to address concerns in various system blocks, from signal generation to detection and interpretation. In an attempt to reduce the cost as well as to increase the integration level and the flexibility of the hardware, the design of sub-systems in CMOS technology is underway. One of the main challenges in this area is with the design of high gain wideband amplifiers. These wideband amplifiers could be used to extract critical frequency information in the time or frequency domain. For the desired bandwidth, a distributed amplifier (DA) is a good option, but has limited power gain. A new method and architecture is proposed for the design of wideband, high gains DAs. As a proof of concept, a DA in the 12-74 GHz range with 19 dB of gain is designed in a digital 90 nm CMOS technology.
Figure 1: Chip micrograph of the distributed amplifier