Influence of feederline modeling of fishbone antenna on calculation results

To ensure accurate electromagnetic modeling, which guarantees the validity of design on fishbone antenna with good performance in the whole short-wave band, the influence of feederline modeling on calculation result is researched. There are two modeling methods for feederline, equivalent network method and wire structure method. On the basis of Pocklington equation and sine interpolation base function, the moment method is used to calculate the short-wave fishbone antenna with the two modeling methods. The results of the antenna pattern, gain, the radiation elevation angle, efficiency and impedance characteristic calculated by the two methods are compared and investigated. Also the influence of the feederline on the radiation characteristic of the fishbone antenna is analyzed. It is indicated that the feederline modeling influences the calculated results greatly. In order to obtain the results consistent with actuality and ensure the validity of the design on the fishbone antenna in the whole short-wave band, the wire structure modeling method for feederline is more appropriate.