Application Cases

Experiment Name: Excitation of Low-Frequency Reconfigurable Magneto-Electric Antennas

Experiment Content: Based on the mechanical oscillation principle of magneto-electric (ME) antennas, this study proposes an ultra-low-frequency reconfigurable ME antenna using a mechanical tuning method. The multidimensional performance of this ME antenna, such as operating frequency, bandwidth, and quality factor (Q), can be adjusted over a large dynamic range without damaging the antenna structure. An equivalent circuit model of the ME antenna was also constructed based on its oscillation theory, and the multidimensional tuning methods of the ME antenna were quantitatively analyzed. Finally, a prototype was fabricated, and the reconfigurable characteristics of the ME antenna were tested in both the mechanical and electromagnetic domains, verifying the feasibility and effectiveness of the mechanical tuning method.

Research Direction: Design of Low-Frequency Reconfigurable Magneto-Electric Antennas

Testing Equipment: ATA-7010 high-voltage amplifier, signal generator, GMI magnetic sensor, spectrum analyzer, etc.

Figure 1: Overall view of the magneto-electric antenna test platform

Figure 2: Detail view of the transmitter end of the magneto-electric antenna test platform

Experiment Process: The frequency-sweeping signal generated by the signal generator is transmitted to the interdigital electrode film of the magneto-electric antenna through the ATA-7010 high-voltage amplifier. Based on the piezoelectric effect, the electric field on the interdigital electrode film is converted into a mechanical wave by the PZT-5H piezoelectric ceramic under the magnetic bias (60 Oe) provided by the Helmholtz coil. Then, the mechanical wave drives the FeGaB thin sheet and induces a magnetostrictive current with the same frequency as the mechanical wave according to the magnetostrictive effect. Finally, the magnetostrictive current generates a radiated magnetic field, which is captured by the GMI magnetic sensor located 0.9 meters away from the antenna. The information from the magnetic sensor is then sent to the spectrum analyzer to obtain the amplitude-frequency response and attenuation characteristics of the magneto-electric antenna in the electromagnetic domain.

Experiment Results:

Figure 3: Simulation results of the frequency response characteristics of the magneto-electric antenna

Figure 4: Test results of the frequency response of the magneto-electric antenna

The test results in both the mechanical and electromagnetic domains are shown in Figures 3 and 4. It can be seen that the frequency response characteristics of the ME antenna in both domains are in good agreement with the results of the equivalent circuit under different spring conditions. The experimental results show that the operating frequency, bandwidth, and Q value tuning ranges are 138-1133 Hz, 14-222 Hz, and 2.85-22.57, respectively. This technology is expected to solve the existing narrowband problem of magneto-electric antennas and the working frequency deviation problem in antenna array applications.

Power Amplifier Recommendation: ATA-7010 High-Voltage Amplifier

Figure: Specifications of the ATA-7010 High-Voltage Amplifier