Introduction
This document describes the design, fabrication, and radio electrical characterization (S11 parameter and radiation) of a set of
seven antennas associated with their electronic board, operating on the ISM 2.45 GHz frequency band and available for the
STM32WB Series microcontrollers.
The seven antenna types are:
• Monopole T-shaped antenna
• Monopole L-shaped antenna
• Inverted F Antenna – IFA
• Microstrip meandered monopole antenna
• IFA metal plane antenna
• Yagi-Uda antenna
• Chip antenna
On-board antennas reference design for the STM32WB Series MCUs
AN5434
Application note
AN5434 - Rev 1 - January 2020
For further information contact your local STMicroelectronics sales office.
www.st.com
1 Reference board
These antennas are benchmarked with the MB1623 board, equipped with an Arm
®
Cortex
®
-based
microcontroller. This board is 40 mm high and 30 mm wide, and the connector is centered along the width at the
top, as shown in Figure 1. Considering the limited dimensions compared to the operating wavelength, as well as
the MB1623 board orientation that can adjust the antenna radiation properties, the proximity of the board must be
taken into consideration during the design process.
Figure 1. Reference board
Design and manufacturing
The following section focuses on the design and fabrication of the antennas. In each sub-section, the simulated
radio-electrical performances of each antenna type are presented. In addition, a section is dedicated to the
fabrication of the antenna prototypes.
Note: Arm is a registered trademark of Arm Limited (or its subsidiaries) in the US and/or elsewhere.
AN5434
Reference board
AN5434 - Rev 1
page 2/44
