9 Conclusion

The examples above use 868-MHz and 2.4-GHz band antennas, but similar measurement and matching techniques can be implemented for any frequency range and any type of antenna.

Consider future antenna parameters at the designing phase. If users want to use your own specific antenna, like helical, rod, or PCB, or antenna from reference design or evaluation board, the antenna's impedance should be matched or tuned. Users cannot predict what the unmatched impedance value will be as it depends on many factors (common ground plane, casing, objects around, and so on). Without VNA at the lab it is hard to understand what the parameters of your antenna are. But at least they can be measured to minimize negative effects. So, it is better to measure and match the impedance on a real board in real conditions before a design is fixed, otherwise, there is almost nothing users can do to get better range.

For PCB design users can refer to a document: CC13xx/CC26xx Hardware Configuration and PCB Design Considerations (Rev. F). For crystal selection refer to a document: Crystal Oscillator and Crystal Selection for the CC26xx and CC13xx Wireless MCUs (Rev. I).

Components 0201 of size are preferable, especially for matching, as they have tight tolerances and small value step, for example, capacitors kit muRata p/n: GJM03-KIT-TTOL-DE or Wurth Elektronik capacitors and inductors kits 744 765 and 885 390 can be used.

Use Pi-network layout on a board at least for prototypes. It will help to use most of network configurations for antenna matching job.