A low frequency tunable broadband design using printed dual-spiral C-patch antenna strip

It was found that an antenna strip with loaded capacitors, i.e., a C-Patch strip, could operate with electrical small radiator. A comparison of the measurements shows that there is a clear antenna gain difference between the high frequency and low frequency regions. Although the antenna gain does peak up at the tuned frequency, one will wander whether it could be improved more A spiral antenna is a broadband antenna that has been widely used in many applications. A combination of the antenna strip with the spiral shapes could bring the high gain antenna region down to the appropriate frequency. In this paper, the effort of combining the C-Patch technology with a dual spiral antenna will be presented.