Wavenet Technology Pty Ltd. BM3900M Manuel D’Utilisation

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Boomer-III User Manual & Integrator’s Guide_________________________________________________Installation 
 
BM310012WT05 
37 
Copyright Wavenet Technology © October 2003 
Selecting & Positioning the Antenna  
Use this information to assist you in selecting the appropriate antenna 
to incorporate into your product package. For specific detailed 
information, Wavenet recommends that you use the expertise of an 
antenna design engineer to solve individual application concerns. Also 
always consult the appropriate technical representative of the target 
network operator prior to selecting and / or designing the antenna, so 
that it will pass network certification requirements. 
Antenna Safety 
The design of the integrated product must be such that the location 
used and other particulars of the antenna comply with the appropriate 
standards of the country in which the host/terminal is to be used. 
The integrator should refer to the statement of Compliance on page 8 of 
this manual and Regulatory Requirements section on pages 19-xx for 
country requirements. 
Mobile and Portable Devices 
In the environment where portable devices are in use, many variables 
exist that can affect the transmission path. In this case, it would be 
preferable to use a vertically polarized, omni directional antenna. 
Antennas for portable devices include the following designs: 
Internal antenna (invisible or pull-up)  
An internal antenna must provide a gain sufficient to meet network 
specifications. Cable routing from the modem to the antenna needs to 
avoid RF sensitive circuits and high level, high-speed clock circuits. 
Consider: 
 
The location of the antenna to avoid RFI to a computing device. 
 
Good shielding to the display and other RF-sensitive 
components 
 
The most efficient method of cable routing 
Otherwise, antenna gain can be offset by cable loss. A typical coaxial 
cable is very thin, such as RG178B used in portable devices, and cable 
loss can be 1dB or more per metre. Some coaxial cable manufacturers 
market relatively thin double braid coaxial cables. These cables show 
much better isolation than single braid cables, typically by 30 to 40dB. 
These double braid cables reduce radiation and RF pick-up when 
routed inside a portable device. 
External antenna, removable and directly connected to the device  
You can design a portable device that can use an off-the-shelf, plug-in 
antenna, such as a ¼ wave monopole or ½ wave dipole antenna. 
Typical gain of these omni directional antennas is 0dBi and 2.14dBi, 
respectively.