Optimized Corrugated Tapered Slot Antenna for mm-Wave Applications

We present a novel approach to design a high-performance tapered slot antenna (TSA) at millimeter-wave frequencies. Commonly, TSAs are designed using profiles expressed as simple functions (linear, exponential, Fermi, or constant width). Some improvement can be achieved by the use of corrugations of fixed dimensions. This usual approach, however, gives little room for improvement in their performance. To overcome this situation, we have developed a new approach: the use of a nonspecific profile and variable corrugations along the antenna, both of which can be optimized to considerably improve its performance. For the optimization, we have used a particle-swarm algorithm allowing us to achieve an excellent performance in the entire W-band. To demonstrate the efficiency of this new approach, we have implemented an optimized antenna using standard printed circuit board (PCB)-prototyping methods. Across the whole W-band, the constructed antenna shows sidelobe levels, reflection coefficient, and cross polarization below -16, -10, and -25 dB, respectively. These results are in good agreement with simulations which also predict possible operation down to 60 GHz. Finally, given its small footprint and the fact that it has been fed by a microstrip line, this antenna can be used in compact electronics providing excellent performance such as that required in radio astronomy or telecommunications.