Application Cases

Experiment Name: Study on Characterization of Antenna Radiation Performance

Research Direction:
By fabricating a prototype of an acoustic-driven low-frequency magnetoelectric antenna, constructing a testing platform, and completing measurements of the antenna's radiation characteristics.

Testing Equipment: ATA-2041 high-voltage amplifier, function generator, spectrum analyzer, low-noise amplifier, coil, antenna, etc.

Experimental Procedure:

Figure 1: Radiation Performance Testing Platform

Using the testing platform constructed as shown in Figure 1, a series of fundamental performance parameters of the antenna, such as radiation intensity, radiation pattern, and efficiency, can be obtained. As illustrated, a sinusoidal wave is generated by an RF signal source and amplified by the ATA-2041 high-voltage amplifier. The amplified signal is applied to the piezoelectric electrode of the magnetoelectric antenna to generate electromagnetic waves. The electromagnetic waves are received by a 200-turn coil and then amplified by a low-noise preamplifier (ATA-5520 small-signal preamplifier). The amplified signal is fed into a spectrum analyzer. The voltage value obtained directly from the spectrum analyzer must be converted to determine the magnetic field strength.

Experimental Results:

Figure 2: Effect of DC Magnetic Bias on Antenna Radiation Intensity (a) Bending Resonance (b) Length Shear Wave Resonance (c) Width Lamb Wave Resonance

Figure 2 illustrates the relationship between the radiation intensity of the antenna's different operating modes and the DC magnetic bias. As shown in the figure, the radiation intensity of the antenna's three operating modes initially increases and then decreases with increasing DC magnetic bias. When the thickness ratio of the magnetostrictive layer is 0.5, the radiation intensity of all three operating modes reaches its maximum. This aligns with the simulation results, which indicate that the optimal thickness ratio of the magnetostrictive layer is 0.5. Under these conditions, the antenna operates at a frequency of 45.72 kHz in the length resonance mode, with dimensions of 40×10×0.8 mm³, meeting the design specifications for antenna frequency and size.

Figure 3: Relationship Between Optimal DC Magnetic Bias and Metglas Layer Thickness

Figure 3 demonstrates the effect of Metglas layer thickness on the optimal DC magnetic bias for different operating modes. As shown, the optimal DC magnetic bias is smallest for bending resonance (approximately a few Oe) and largest for width Lamb wave resonance (over one hundred Oe). As the thickness of the Metglas layer increases, the optimal DC magnetic bias for antenna operation also increases. Different operating modes exhibit distinct optimal DC magnetic bias values. Therefore, by applying an appropriate DC magnetic bias, the radiation intensity of the antenna can be significantly enhanced. Finally, the DC magnetic bias can be optimized based on the operating mode and Metglas layer thickness.

Voltage Amplifier Recommendation: ATA-2041

Figure: ATA-2041 High-Voltage Amplifier Specifications

The experimental materials in this article are compiled and published by Xi'an Aigtek Electronics. For more experimental solutions, please continue to follow the Aigtek official website.