NINA-W1 series - System Integration Manual
UBX-17005730 - R07
Design-in
Page 33 of 47
similar to one quarter of wavelength of the minimum frequency that has to be radiated; however
overall antenna efficiency may benefit from larger ground planes.
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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,
ferrite sheets and so on as they may absorb part of the radiated power or shift the resonant
frequency of the antenna or affect the antenna radiation pattern.
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It is highly recommended to strictly follow the detailed and specific guidelines provided by the
antenna manufacturer regarding correct installation and deployment of the antenna system,
including 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 to consult the
antenna manufacturer for the design-in guidelines and plan the validation activities on the final
prototypes like tuning/matching and performance measures (see Table 3).
•
RF section may be affected by noise sources like hi-speed digital buses. Avoid placing the
antenna close to buses such as DDR or consider taking specific countermeasures like metal
shields or ferrite sheets to reduce the interference.
⚠
Take care of interaction between co-located RF systems like LTE sidebands on 2.4 GHz band.
Transmitted power may interact or disturb the performance of NINA-W1 modules.
3.3.3
On-board antenna design (NINA-W102/W132/W152 only)
If a plastic enclosure is used it is possible to use NINA-W1 with embedded antenna. In order to reach
optimum operating range the following instruction shall be implemented.
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The module shall be placed in the corner of the host PCB with the antennas feed point in the
corner (pin 15 and 16), according to Figure 22. Other edge placements positions, with the
antenna closest to the edge, are also possible. These will however give moderate reduced
antenna performance compared to the corner placement.
•
A large ground plane on the host PCB is a prerequisite for good antenna performance.
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The host PCB shall include a full GND plane underneath the entire module, including the antenna
section. This to facilitate efficient grounding of the module.
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High / large parts including metal shall not be placed closer than 10 mm to the modules antenna.
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At least 5 mm clearance between the antenna and the casing is needed. If less than 5 mm can be
achieved the antenna performance will be affected. PC and ABS gives less impact and POS type
plastic gives more.
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The module shall be placed such that the antenna faces outwards from the product and is not
obstructed by any external items in close vicinity of the products intended use case.
