Near-field calibration method for relative amplitude and phase characteristics of spherical surface array antenna channels

Abstract

The invention provides a near-field calibration method for relative amplitude and phase characteristics of spherical surface array antenna channels, and aims to provide a method with few calibration source and capable of automatically performing self-correction on the relative amplitude and phase characteristics. The near-field calibration method is characterized in that: calibration frames distributed around a spherical surface antenna array plane are set up on the periphery of a phased-array antenna and a calibration frame is set up at the center of the phased-array antenna, thus a conformalspherical surface array distribution model for antenna unit approximate uniform distribution is formed; optical equipment is used for performing high-precision measurement on a coordinate position ofeach calibration antenna relative to a central point of the spherical surface array antenna, and a spatial distance and an axial included angle between each array element on the spherical surface array antenna and each calibration antenna are calculated; and a calibration reference signal generated by calibration test equipment is used for calibrating uplink / downlink channels of the spherical surface array antenna, and amplitude / phase characteristics of element antenna channels are obtained through deducting relative amplitude and phase characteristics of the antenna and amplitude / phase changes introduced by the spatial distances and axial deflection between each calibration antenna and each array element.

Description

technical field [0001] The invention relates to a method for calibrating the relative amplitude and phase characteristics of the spherical phased array antenna channel in the field of radar and aerospace measurement and control Background technique [0002] Phased array antennas come in many forms, such as linear arrays, planar arrays, circular arrays, cylindrical arrays, spherical arrays, spherical arrays, and conformal arrays that conform to more complex surfaces. The shape of the traditional antenna array is generally spherical, and the electric axis of the antenna feed element installed on it points to the center of the spherical antenna array. During the test, the phase center of the antenna of the equipment under test is required to coincide with the center of the sphere to ensure the simulation accuracy of the signal position of the radio frequency radiation source and accurately control the amplitude of the signal power. Due to the inconsistency of the clocks at the...

AI Technical Summary

Problems solved by technology

Since the radiation characteristics of the unit antenna in the active space are not equal gain, there are also quantization errors and calibration errors in the beam forming process, which will affect the accuracy of the pointing and level of the beam at different scanning angles

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