Among many crucial components of wireless network is the antenna. It is needed to transmit and receive data. The type of antenna used will determine the gain, radiation pattern and signal propagation. You should choose an antenna with specific pattern that fully maximizes radio signal efficiency. WiFi network could operate in 2.4GHz or 5GHz frequency, so make sure that you choose the right antenna. In many countries there are restrictions of power that a wireless network can transmit, which usually at around 1 Watt. Reduced power wattage ensures that there will be less interference with adjacent networks.
Antenna gain indicates the amount of effective signal power that an antenna raises for a specific input power. Gain is measure in dB or decibels. dB is calculated using logarithmic scale. It means, if an antenna has 3dB gain, then it will double the power. As an example, with a 25mW input, the antenna could produce 50mW output. Here are types of WiFi antenna that you may choose:
- Omni-Directional Antennas: Omni directional means that signals are emitted to all directions. It means that the signal coverage will have a doughnut shape. However, true omni directional signal propagation is often theoretical. Obstructions could prevent signal to travel far at some areas.
- Vertical omni: Vertical omni antenna has dipole design with radiation pattern of 360 degrees based on the horizontal plane. Average gain for dipole antennas is about 2dB.
- Ceiling domes: Ceiling dome antennas are mounted on the ceiling at the false ceilings. You may also mount ceiling dome antenna on the wall. Due to their better positioning, these antennas have good gain at about 3dB.
- Rubber duck: Rubber ducl antennas are also known as electrically short antennas. They usually have wire-like element with rubber sheathing cover. This makes rubber duck antennas robust and more flexible compared to other rigid antennas. They are often vertically mounted with 360 degree pattern of radiation. There are currently many rubber duck antennas for wireless routers.
- Yagi: Yagi antennas are known for their high gain. Their multiple radiation elements and reflector could offer between 12Db and 20dB of gain. Yagi antennas are ideal for outdoor uses. They are acceptable if you want to cover more distance for users who are located outdoor.
- Dish: Dish antennas have parabolic design. Which direct the waves to specific direction. Dish antennas can have up to 50B gain at certain areas. Dish antennas are good if you focus on a fixed are.
- Patch antennas: Patch antennas are usually attached on the wall. They can also be mounted on the ceiling. Horizontal beamwidth of antennas are usually around 80 degrees. Patch antennas with half-wavelength design offers about 2dB of gain.
Most WiFi network use vertical dipoles or dome antennas. If you want to maximize coverage of the wireless network, you may choose patch, dish or yagi antennas. If you are not sure, ask sellers or local experts about what type of antenna that’s good for you