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A dipole antenna is a common type of radio antenna that consists of two identical conductive elements such as metal wires or rods. These elements are typically bilaterally symmetrical with each other, and the radio signal is fed into the antenna at the center between these two elements.

In the context of a Printed Circuit Board (PCB), a dipole antenna can be designed by etching two lines of equal length on the board, positioned end to end with a small space between where the feed line connects. The dipole antenna is one of the simplest and most widely used antenna setups.

Key characteristics of dipole PCB antennas:

•Design and Implementation: In its simplest form, the length of each side of a dipole antenna should be approximately one quarter of the wavelength (λ/4) of the intended operating frequency. The overall length of the antenna then becomes half the wavelength (λ/2).

•Directionality and Polarization: Dipole antennas are omnidirectional when viewed from above (from the perspective looking down the axis of the two elements), meaning they radiate radio waves equally in all horizontal directions. They typically produce linearly polarized waves.

•Balanced Antenna: A dipole is a balanced antenna, meaning it does not require a ground plane to function. This can be beneficial in situations where the introduction of a ground plane is impractical.

•Applications: Due to their simple design, balanced operation, and omnidirectional radiation pattern, dipole antennas are often used in various wireless communication systems, including WiFi, Bluetooth, and other radio communication systems.

When designing a dipole PCB antenna, it's essential to take into consideration factors such as the frequency of operation, the dielectric constant of the PCB substrate, and the thickness of the copper layer. Other components and traces on the PCB can also impact the performance of the antenna, and these factors should be carefully evaluated and possibly simulated before the final design is decided.

After fabrication, it is typically necessary to measure and tune the antenna in a real-world environment to ensure optimal performance. This process typically involves trimming the length of the antenna elements to resonate at the desired frequency.