Antenna matching
If you use radio modules, you need an antenna. If you have an antenna built into your device, you need to match it. Any antenna, regardless of its type, requires matching after it is integrated into the printed circuit board. Antenna matching is also required when changing the design of the printed circuit board. Antenna matching will ensure its optimal operation. This means that:
- the maximum amount of energy will be transmitted from the transmitter to the antenna and from the antenna to the receiver,
- allows you to use the minimum transmit power,
- which in turn will make it easier for you to get certified and reduce overall energy consumption.
From 2020 to the present day, we have matched dozens of antennas of different types. We work a lot with PCB-trace antennas in the 2.4 GHz range, due to their low cost, fairly small size and good performance. The typical range of a stable radio connection in our products in the 2.4 GHz range and a transmit power of 0 dBm is 50 meters, without obstacles.
Important things to consider when matching an antenna:
- you are matching the antenna on the device with the device case. The device case can make significant changes, especially if it is located close to the antenna.
- you are matching the antenna on the complete device, not just the radio module. After you mount your radio module on another board, the antenna characteristics will change,
- your measuring equipment is calibrated at the point of connection to the board.
We usually use the so-called π-network. This approach allows us to match almost any antenna using one, two, or three components (capacitors or inductors).
Matching is done by selecting/changing components of the matching network and then measuring the system's performance. Measurements are made using a spectrum analyzer with a built-in tracking generator and specialized software.