Sierra AirPrime MC7750, Руководство по интеграции оборудования

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AirPrime MC7750 Hardware Integration Guide
14 Proprietary and Confidential 2130114
RF connection
When attaching an antenna to the module:
Note: To disconnect the
antenna, make sure you
use the Hirose U.FL
connector removal tool
(P/N UFL-LP-N-2(01)) to
prevent damage to the
module or coaxial cable
assembly.
• Use a Hirose U.FL connector (model U.FL #CL331-0471-0-10) to attach an
antenna to a connection point on the module
.
• Match coaxial connections between the module and the antenna to 50

• Minimize RF cable losses to the antenna; the recommended maximum cable
loss for antenna cabling is 0.5 dB.
Ground connection
When connecting the module to system ground:
• Prevent noise leakage by establishing a very good ground connection to the
module through the host connector.
• Connect to system ground using the two mounting holes at the top of the
module.
• Minimize ground noise leakage into the RF.
Depending on the host board design, noise could
potentially be coupled to
the module from the host board. This is mainly an issue for host designs that
have signals traveling along the length of the module, or circuitry operating at
both ends of the module interconnects.
Shielding
The module is fully shielded to protect against EMI and to ensure compliance with
FCC Part 15 - “Radio Frequency Devices” (or equivalent regulations in other
jurisdictions).
Note: The module shields must NOT be removed.
Note: Values in this guide
are taken from the appro-
priate product specifi-
cation documents (PSDs)
—in the case of a
discrepancy between this
document and the relevant
PSD, use the value listed
in the PSD.
Antenna and cabling
When selecting the antenna and cable, it is critical to RF performance to match
antenna gain and cable loss.
Choosing the correct antenna and cabling
Consider the following points for proper matching of antennas and cabling:
• The antenna (and associated circuitry) should have a nominal impedance of
50

with a return loss of better than 10 dB across each frequency band of
operation.
• The system gain value affects both radiated power and regulatory (FCC, IC,
CE, etc.) test results.