Bandwidth Comparison of Traveling-Wave and Standing-Wave Array Designs of Series-Fed Microstrip Patch Array Antennas

A series-fed microstrip patch array antenna is applied to reduce the feeding loss in millimeter-wave band. However, the ordinary antenna with standing-wave array design operates in narrow bandwidth. Therefore, the antenna with traveling-wave array design has been developed. In this paper, series-fed microstrip patch array antennas are designed with standing-wave array design and traveling-wave array design. In addition, we design both antennas with different number of patches and compare these performance to confirm the relationship between the number of patches and array designs. As a result of the simulation, the traveling-wave array design provides wide bandwidth for large-element array. The standing-wave array design provides wide bandwidth for small-element array.