NINA-B50 series - Hardware integration manual
UBX-22021116 - R02
Design-in
Page 24 of 57
C1-Public
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Proper placement of the antenna and its surroundings is also critical for antenna performance.
Avoid placing the antenna close to conductive or RF-absorbing parts, such as metal objects and
ferrite sheets, as these may absorb part of the radiated power, shift the resonant frequency of the
antenna, or otherwise affect the antenna radiation pattern.
•
Strict adherence to the guidelines from antenna manufacturer is recommended. Consider carefully
regarding their instructions for correctly installing and deploying the antenna system, including
the design of the PCB layout and matching circuitry.
•
Further to the custom PCB and product restrictions, antennas may require tuning/matching to
comply with all the applicable required certification schemes. It is recommended that you plan
measurement and validation activities with the antenna manufacturer before releasing the end-
product to manufacturing.
•
RF parts may be affected by noise sources like hi-speed digital buses. Avoid placing the antenna
close to buses such as a Double Dara Rate (DDR) bus and consider taking specific
countermeasures like metal shields or ferrite sheets to reduce the interference.
3.2.4
NINA-B506
NINA-B506 modules include an internal PCB trace antenna that is integrated on the module PCB using
antenna technology from Abracon. The RF signal is completely internal and not connected to any
module pin. NINA-B506 modules
can’t
be mounted inside a metal enclosure. Metal casings or plastics
that include metal flakes should not be used. Metallic-based paints and lacquers should also be
avoided.
3.2.4.1
Internal PCB trace antenna
For optimal operating performance, observe the following layout considerations when developing the
antenna layout:
•
The module shall be placed in the center of an edge of the host PCB.
•
A large ground plane on the host PCB is a prerequisite for good antenna performance. A ground
plane extending at least 10 mm on the three non-edge sides of the module is recommend, as shown
in
•
Include a non-disruptive GND plane underneath the module with a cut out underneath the antenna,
as shown in
•
Observe th
e antenna “keep
-
out” area on all layers, as shown in figures
•
NINA-B506 has four GND pads located close to the antenna, as shown in
. Connect these
pads to GND. Detailed dimensions of the footprint, including those related to these GND pads, can
be found in the NINA-B50 series data sheet
•
To avoid degradation of the antenna characteristics, do not place physically tall or large
components closer than 10 mm to the module antenna.
•
To avoid any adverse impact on antenna performance, include a 10 mm clearance between the
antenna and the casing. Polycarbonate (PC) and Acrylonitrile butadiene styrene (ABS) materials
have less impact on antenna performance than other types of thermoplastics.
•
Include plenty of stitching vias from the module ground pads to the GND plane layer. Ensure that
the impedance between the module pads and ground reference is minimal.
•
Connect all ground pads to the ground plane.
•
Consider the end products use case and assembly to make sure that the antenna is not obstructed
by any external item.
