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FSS JODY-W263 Integration Instructions Rev 02.docx
www.foresightsports.com
This document supports a connector-based design for the use of external antennas (one for
each antenna pin of the module).
6.2
General description and requirements
JODY-W2 series modules provide two RF interfaces for connecting external antennas. The
antenna ports ANT0 and ANT1 have a nominal characteristic impedance of 50 Ω and must be
connected to the related antenna through a 50 Ω transmission line to allow proper
impedance
matching along the RF path. A bad termination of the pin may result in poor performance or
even damage the RF section of the module.
For optimal performance in multiradio mode, the isolation between the antennas shall target the
requirements as specified in Table 10 and Table 11
in order to ensure good performance.
Item
Requirements
Remarks
Impedance
50 Ω nominal characteristic
impedance
The impedance of the antenna RF
connection must match the 50 Ω
impedance of the antenna pins.
Frequency range
2400 - 2500 MHz
5150 - 5850 MHz
For 802.11b/g/n and Bluetooth.
For 802.11a/n/ac.
Return loss
S11 < -10 dB (VSWR < 2:1)
recommended
S11 < -6 dB (VSWR < 3:1)
acceptable
The return loss or the S11, as the
VSWR, refers to the amount of
reflected power, measuring how
well the primary antenna RF
connection matches the 50
Ω
characteristic impedance of antenna
pins.
The impedance of the antenna
termination must match as much as
possible the 50
Ω
nominal
impedance of antenna pins over the
operating frequency range, to
maximize the amount of power
transferred to the antenna.
Efficiency
> -1.5 dB ( > 70% ) recommended
> -3.0 dB ( > 50% ) acceptable
The radiation efficiency is the ratio
of the radiated power to the power
delivered to antenna input: the
efficiency is a measure of how well
an antenna receives or transmits.
Maximum gain
The maximum antenna gain must
not exceed the value specified in
type approval documentation to
comply with regulatory agencies
radiation exposure limits.
Table 10: Summary of antenna interface requirements
