Transmissions from the Modem consist of short periods of high current draw conforming to the
following characteristics:
Parameter
Value
Note
Transmission
Length
3.7 s
Length of transmission for sending a 192 byte packet to
space. Actual length may be shorter with a smaller packet
size
Transmission
Energy
3.4
mW-hrs
(12.24 J)
Total amount of energy required for 1 transmission to
space (192 bytes), when using 3.3V
Recovery
Time
0.4s
When sending multiple messages, this is the minimum
amount of time that will pass before the Modem will
attempt another transmission
Table 9:
Sample Modem transmission characteristics for sending a user payload of 192 bytes. Modem provided with
3.3V input.
Other electrical characteristics of the Modem can be found below:
Parameter
Value
Maximum power at antenna connector
1.122 W
Sum total of all capacitance
255 μF
Sum total of all inductance
16790 nH
Largest capacitor
47 μF
Largest inductor
15000 nH
Total Input Capacitance
57 μF
Table 10:
Other electrical characteristics for the Modem
© 2022 SWARM TECHNOLOGIES
SWARM M138 MODEM PRODUCT MANUAL · REV 1.20 · FEBRUARY 2022
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