Antenna Selection Guide for Wireless Wiegand in 900 MHz ISM Band

Selecting the right antenna for a Wireless Wiegand (WW) system in the 900 MHz ISM band is crucial for optimal performance, range, and reliability. WW includes a custom-tuned omnidirectional antenna, optimized for stable and efficient signal transmission.

Impact of Antenna Choice

The antenna directly affects signal distance, connection quality, and interference levels.

For longer distances and specific scenarios, other types of antennas may be preferred. Directional antennas, such as Yagi or panel antennas, can provide increased range and reduced interference by focusing the signal in a specific direction. However, they require precise alignment and are more suitable for point-to-point communication. It's important to consider the specific requirements of your application when selecting an antenna.

Elevation & Placement

Mounting height greatly influences range. Higher placement reduces obstacles and interference from ground reflections and surrounding objects. A clear line-of-sight ensures stronger signals, especially in large-area or outdoor deployments.

1. Omnidirectional Antennas

Omnidirectional antennas provide 360-degree coverage and are ideal for installations where signals need to be transmitted in all directions equally.

Whip Antennas

Description: A flexible, vertical antenna commonly used in access control and wireless communication systems.
Pros: Easy to install, provides uniform radiation in all directions.
Cons: Limited range compared to directional antennas.
Example Applications: Reader-to-controller wireless communication in small office or residential installations.

Dipole Antennas

Description: A two-element antenna with improved efficiency over whip antennas.
Pros: Better performance and range compared to single-element antennas.
Cons: Requires specific mounting orientation for optimal performance.
Example Applications: General-purpose access control setups.

2. Semi-Directional Antennas

Patch (Panel) Antennas

Description: A flat, rectangular antenna that directs signals forward.
Pros: Higher gain than omnidirectional antennas; reduces interference from other directions.
Cons: Limited to fixed mounting positions.
Example Applications: Entry points where signals need to be directed towards specific areas.

3. Highly Directional Antennas

Yagi Antennas

Description: A multi-element antenna designed for high-gain, directional applications.
Pros: Excellent range and efficiency for point-to-point wireless links.
Cons: Requires precise alignment and mounting.
Example Applications: Long-distance communication between remote access control points.

Parabolic (Dish) Antennas

Description: A high-gain dish antenna that focuses signals in an extremely narrow beam.
Pros: Maximum range and minimal interference.
Cons: Bulky and requires precise alignment.
Example Applications: Large industrial or campus-wide access control networks.

Key Considerations for Antenna Selection

1. Frequency Compatibility – Ensure the antenna supports the 900 MHz ISM band.
2. Coverage Needs – Choose omnidirectional for broad coverage, semi-directional for focused areas, and directional for long-range links.
3. Installation Environment – Consider obstructions, interference, and mounting options.
4. Antenna Gain – Higher gain improves range but reduces coverage angle.

Additional Resources

For a deeper understanding of antenna selection and placement, watch this webinar:
Antenna 101 - Choosing the Right Antenna: https://www.youtube.com/watch?v=BAhvJTyNtbg

Custom Cables for Optimal Performance

Using the right cable length is essential to minimize signal loss and interference in Wireless Wiegand and 900 MHz ISM band applications. Pre-cut cables can introduce excess length, causing unnecessary attenuation.

For best performance, it’s recommended to custom-build cables to exact lengths needed for your installation. This reduces unnecessary signal loss and improves system efficiency.

Recommended Custom Cable Supplier

• MPD Digital – Offers custom-built RF cables for 900 MHz antennas, allowing selection of connector types, cable length, and shielding options.
  https://mpddigital.us/cable-builder/

Top Antenna Suppliers and Stores

1. Data Alliance – Wide selection of 900 MHz antennas, including omnidirectional, directional (Yagi, panel), and fiberglass antennas.
• Website
• Example products:
• A9O8NF – 900MHz 8dBi omni fiberglass (N-female)
2. L-Com – One of the best shops for diverse antenna selection, including HG90X series and high-gain Yagi and patch antennas.
• 900 MHz Yagi Antennas
• Example products:
• HG908U-PRO – 900 MHz 8 dBi Omnidirectional Antenna ($173)
3. Digi-Key – Offers Laird, Nearson, and MikroTik antennas. Good for sourcing 900 MHz monoband and window-mount antennas.
• Website
4. Taoglas – Specializes in high-performance LoRa and external antennas.
• LoRa Antennas
5. GridConnect – Supplier of RAK LoRa antennas.
• Example product: RAK LoRa ANTENNA – FIBERGLASS, 5.8 dBi, N-TYPE to SMA ($50)
6. Nearson Antennas – Offers window-mounted 4 dBi antennas and custom solutions.
7. MikroTik – Known for monoband antennas suitable for industrial applications.

Conclusion

Selecting the right antenna for a Wireless Wiegand system in the 900 MHz ISM band depends on specific application needs. Whether requiring full 360-degree coverage, directional focus, or long-range connectivity, the right choice ensures optimal system performance and reliability.