Microwave Imaging With a Reduced Number of Transmission Channels in a Semi-Circular Antenna Array

Muscle injuries, particularly in the muscles composing the hamstring, pose significant challenges in sports medicine. Our aim is to use microwaves for the diagnosis of such injuries with a compact and low-cost system. A primary challenge with compact systems is the measurement time, caused by the time needed to switch between transmission channels. In this study, we explore the potential for reducing the number of transmission channels in a semi-circular antenna array and its impact on reconstruction accuracy. We hypothesized that antennas closer to each other are more important for accurate reconstruction due to their higher coherency, signal strength and lower noise levels compared to distant antennas. Thus, the farthest antennas may be excluded from measurements and reconstructions. Using both simulations and measurements, we systematically decreased the number of transmission channels to observe the effects on the reconstructed image. Our findings demonstrate that it is feasible to reduce the number of transmission channels by omitting the farthest antennas from 56 down to 36 channels while limiting the reduction in Signal to clutter ratio (SCR) to less than 12%.