A Conical Logarithmic Spiral Antenna with an Inclined Axis

When constructing the array of conical logarithmic spiral antenna, the performance of the array antenna with be degraded when the effective radiation zone spacing exceeds one wavelength or the unit radiation direction is inconsistent. In this paper, a kind of conical logarithmic spiral antenna with an inclined axis is proposed. By continuously shifting the conical logarithmic spiral antenna structrue to one side, the axis tilt can be realized while the radiation structure still faces the z-axis direction. Its radiation direction is kept along the z-axis direction, which has the characteristics of " axis inclined, pattern less inclined " , which can solve the problem of performance degradation of the conical logarithmic spiral antenna array. Aiming at the complex structure of the inclined conical logarithm spiral antenna, a method of unwinding the inclined helix is presented, so that the antenna can be processed by flexible PCB technology. In this paper, an inclined conical logarithmic spiral antenna with axis tilt of 20° is designed and implemented. The maximum deviation of the measured pattern is 11. 8°, which verifies the effectiveness of the proposed antenna.