In this video from Würth Elektronik you will learn about antenna matching with PCB board.
Developing a Smart Product with Optimal Antenna Matching
In the development of smart products utilizing Wi-Fi modules, the integration of a multi-layer chip antenna on the board is crucial. Initial attempts to solder an antenna onto a standard demo board revealed the need for expert guidance to achieve proper antenna matching.
Understanding Antenna Matching
Antenna matching is a critical process that ensures optimal signal transmission and reception. The diagram below illustrates a typical PCB layout, featuring a return plate or antenna, a signal line, and a matching circuit. It is important to note that this antenna design does not require a ground plane beneath it. The current matching for the 2.4 GHz frequency is suboptimal, as observed. To address this, a capacitor was added to the signal line, resulting in improved matching. However, this solution is not suitable for Wi-Fi applications, as it only covers a broader frequency range.
The Role of a Matching Circuit
A matching circuit generally consists of two or three components. While a single capacitor can provide a matching circuit for various frequencies, our focus must be on the specific 2.4 GHz range. Incorporating inductance into the circuit offers a more effective solution.
A Promising Solution
The integration of inductance has led to significant improvements. The performance now spans from 2.4 to 2.5 GHz, with excellent session loss, indicating a 100 MHz bandwidth. This ensures that nearly the entire signal passes through the antenna, with only 15% signal loss, which is acceptable. However, it is anticipated that integrating this solution into the actual board may yield different results. Rematching will be necessary not only with the board but also with the enclosure, as environmental factors can influence performance. To mitigate this, a non-metallic enclosure is recommended.
This development not only benefits individual projects but also presents an opportunity to offer antenna matching services to customers. Our antenna matching team is available to assist with product development, ensuring optimal performance across various environments.