Novel Directional Antennas for Microwave Breast Imaging Applications

In this paper, an ultra-wideband (UWB) antenna with highly directional property is developed for microwave breast imaging applications. Two different patch antennas are designed to obtain the required performance. The proposed two different novel designs of a square and circular patch antenna show a reflection coefficient less than -10dB over a frequency range of 1. 4GHz to 10 GHz. The gain of the square and circular patch antenna is 6. 06dB and 5. 5dB whereas the directivity of the square shape antenna and circular patch antenna is 8. 37dBi and 6. 96dBi. The important characteristics of these square and circular antenna schemes are the cautious engineering of the ground plane with etching a slot having a width of 2.25mm on the ground plane margin, which authorizes the wide bandwidth over the complete UWB range. By introducing the gap in between the ground and patch plane, lower frequency band of operation is attained. The proposed two different antennas shows directional radiation pattern, wide bandwidth and good gain which is enough for the microwave imaging application. The VSWR is less than 2 over the entire range of UWB band.