Designing 1.4m Long Microstrip Antennas for 45 kHz: Challenges and Solutions

Creating a 1.4m long straight line microstrip antenna that resonates at 45 kHz seems like a straightforward task, but it brings up a host of challenges. In this article, we will explore the feasibility of such an antenna, the physics behind its design, and the limitations it faces in practical applications.

Resonance in Microstrip Antennas

When designing a microstrip antenna that is 1.4 meters long for 45 kHz, we can create a resonant circuit. This is achieved by including an inductor and a capacitor. In this specific case, the inductance calculated for the microstrip transmission line at 45 kHz is approximately 2 micro;H. The capacitance required to resonate this inductance is about 6.6 micro;F. While this setup ensures an electrical resonance at the desired frequency, its practical applications are limited.

Theoretical and Practical Limitations

One of the primary limitations of this 1.4m antenna is its inability to effectively radiate or receive signals at the 45 kHz frequency. To achieve radiation, an antenna needs to be at least 0.1 wavelength long. At 45 kHz, the wavelength can be calculated using the formula: wavelength speed of light / frequency. This gives a wavelength of approximately 6662 meters.

Therefore, to radiate efficiently at 45 kHz, the antenna would need to be around 660 meters long. This impractical length highlights the fundamental challenge in using a 1.4 meter long microstrip antenna for such a frequency.

Alternative Antenna Designs

While a 1.4m long microstrip antenna specifically for 45 kHz is not practical, other small antenna solutions might still be considered for this frequency. However, even these alternatives may not be very efficient. Small antennas designed for higher frequencies, such as those in the radio frequency (RF) range, might offer better performance.

Key Considerations:

Resonance: Ensuring that the antenna resonates at the desired frequency is crucial for its performance. Inductive Properties: Understanding the inductive properties of the microstrip transmission line is essential for accurate design. Practical Length: Practical antenna dimensions must be considered to ensure that the antenna can effectively radiate or receive signals.

Conclusion

In summary, while a 1.4 meter long microstrip antenna can be designed to resonate at 45 kHz, it is not suitable for practical applications due to its inability to effectively radiate or receive signals. Designing antennas involves a balance between theoretical resonance and practical performance. For this frequency, alternative antenna solutions or higher frequency technologies might be more appropriate.

Keywords

micstrip antenna, resonance, 45 kHz, antenna design, inductive