XStream™ Advanced Programming & Configuration

XStream Advanced Programming & Configuration – Advanced Manual v4.2A
Antennas
[See Appendix A for a list of FCC-Approved Antennas]
Factors that determine RF link range:
• Ambient RF noise (interference)
• Line-of-sight obstructions
• Transmit power
• Receive sensitivity
• Antenna configuration
Factors that affect antenna performance:
• RF cable length
• Height of antennas off the ground
• Obstructions
• Radiation pattern
• Antenna Gain
XStream Antenna Connector Options
In order to comply with the FCC rules and obtain a “modular” certification, it is required that the
XStream Modules utilize a “non standard” connector. This is to ensure that the radios are used
only with approved antennas. The XStream radio modules have two connector options:
• RPSMA
• MMCX
• N-Connector
RPSMA
[Available for OEM Modules & RF Modems] The Reverse Polarity SMA
(RPSMA) connector uses the same body as a regular SMA connector. In
order to be a “non standard” connector, the gender of the center
conductor is changed. The female RPSMA actually has a male center
conductor.
MMCX
[Available for OEM Modules only] The Micro-Miniature connector
(MMCX) is a good solution for high volume, price-sensitive
applications. The small size and snap on connection make it
suitable for attaching an external mounted antenna to a radio
module inside an enclosure.
N-Connector
[Available for OEM Modules & RF Modems] An N-Connector does not come installed on the
XStream Modules, but is a common connector used with higher gain antennas such as the Yagi.
MaxStream can supply “RPSMA to N-Connector” cables in various lengths.
Antenna Cables
RF cables are typically used to connect a radio installed in a cabinet to an antenna mounted
externally. As a general rule, it is best to keep the RF cable as short as possible. All cables have
losses which are usually measured in dB loss per 100 ft. MaxStream has cables available made
with LMR-195. Some common cables and dB losses are included in this table:
Table 4.
Potential Signal Strength Loss due to Antenna Cable Length
Cable Type
Loss at 900 MHz per 100’
(loss per 100m)
Loss at 2.4 GHz per 100’
(loss per 100m)
Diameter Inches
(mm)
RG-58 14.5 (47.4) dB 25.3 (83.2) dB 0.195 (4.95)
RG-174 25.9 (85.0) dB 44.4 (145.84) dB 0.100 (2.54)
RG-316 24.7 (81.0) dB 42.4 (139.0) dB 0.102 (2.59)
LMR-195 11.1 (36.5) dB 19.0 (62.4) dB 0.195 (4.95)
LMR-240 7.6 (24.8) dB 12.9 (42.4) dB 0.240 (6.10)
LMR-600 2.5 (8.2) dB 4.4 (14.5) dB 0.590 (14.99)
© 2004 MaxStream, Inc., Confidential and Proprietary 14