Design of a single null compensation dipole antenna

Abstract

In this paper, a single null compensation dipole antenna for Wi-Fi band (2.4 GHz) is developed. The antenna is fed by the parallel transmission lines, and its radiation unit consists of a printed dipole antenna and a Yagi antenna. The proposed antenna has three layers. The top and bottom layers are printed with the dipole antenna and the driver arm of the Yagi antenna. The director and the reflector of the Yagi antenna are placed on the middle layer. The three layers are separated by two FR-4 substrates. This antenna satisfies the omnidirectional radiation characteristic in its H plane and can compensate a null point in the E plane. Simulation results show that the 10 dB bandwidth is 2.32 to 2.46 GHz. The maximum realized gain is 1.13 dB in the frequency band. The non-roundness of the H plane is less than 2 dB, which shows good omni-directivity. A null point in the radiation pattern of the E plane is compensated to −1.4 dB at 2.4 GHz, while the other null point of the E plane remains below −15 dB. The antenna has been manufactured and tested, and the measurement results validate the design and the simulation results.