Hardware Configuration Instructions
for TTRF Infrastructure
©
SENSITECH INC
REV A
9/6/2005
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TempTale® RF System
The TempTale® RF system uses software and hardware to capture temperature data and
download the data wirelessly to a local computer. The data is then sent via Internet to a secure
database where the data can be viewed and analyzed. The software is Remote Site Server
(RSS) and the hardware is; TempTale RF monitors (TTRF) and three other types of RF (Radio
Frequency) devices:
•
Gateways - are RF monitor readers attached via Ethernet to the PC running RSS
•
Repeaters - extend the area covered by the network.
•
Signposts - transmit a location ID which is stored in the monitors.
Depending on geographic region, the TTRF system operates within two ISM (Industrial, Scientific
and Medicine) frequency bands:
870.0 MHz in Europe and
928 MHz in North America
Within these bands, the TTRF System uses specific channels to transmit and receive data. For
the 902 - 928 MHz band the following channels are used:
914.904 MHz
922.277 MHz
For the 869 MHz band the following channel is used:
869.850 MHz
The RF signal used is a narrow band transmission that transmits power at +2 dBm for the
monitors and 0dBm for the Infrastructure (Gateway, Repeaters and Signposts). Both the monitor
and Infrastructure devices have an ERP (Effective Radiated Power) of about 2dB below the FCC
limit of 94 dB µV/m. The channel width is 185 kHz, with 99% of energy within this channel. For
US TTRF systems, the RF infrastructure (Gateways, Repeaters and Signposts) will be set to one
of the two channels based on the current S/N (Signal to Noise) ratio of all the available channels
at the time the system is installed at a customer site. The operating channel can be manually
changed at any time if there is too much noise (i.e. interference) on the current channel
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.
US operating TTRF systems (using the 902 – 928 MHz ISM band) conform to FCC rule Part 15,
Section 249, which states:
The field strength of emissions from intentional radiators operated within these frequency bands
shall comply with the following:·
•
Fundamental Frequency field strength: 50 millivolts/meter·
•
Harmonics Frequency field strength: 500 microvolts/meter
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For European operations, there is currently only one channel to use for the TTRF system.
