Antenna Matching
If your product uses a radio module, it requires an antenna — and once that antenna is integrated into the printed circuit board (PCB), it must be properly matched. This applies to all antenna types, and matching must be repeated whenever the PCB design changes.
Proper antenna matching ensures optimal RF performance, which means:
- Maximum energy transfer from the transmitter to the antenna and from the antenna to the receiver
- The ability to operate at the lowest possible transmit power
- Easier regulatory certification and reduced overall power consumption
Since 2020, we’ve matched dozens of antennas of various types. We frequently work with PCB-trace antennas in the 2.4 GHz band, as they offer low cost, compact size, and good performance. In our products, a typical stable radio range at 2.4 GHz with a transmit power of 0 dBm is around 50 meters in open, unobstructed conditions.
Important considerations when matching an antenna:
- Match the antenna in its final enclosure.
The device enclosure can significantly affect antenna performance, especially if it is close to the antenna. - Match the complete device, not just the radio module.
Once a radio module is mounted on a different PCB, the antenna characteristics will change. - Ensure measurement equipment is calibrated at the PCB connection point.
Accurate calibration at the point where the antenna connects to the board is essential for reliable matching results.
We typically use a π-network matching circuit, which allows us to match almost any antenna using one, two, or three components (capacitors and/or inductors).
Matching is performed by selecting and adjusting the components of the matching network, followed by measuring the system’s performance. Measurements are carried out using a spectrum analyzer with a built-in tracking generator and specialized software.