Swarm M138 User manual

Swarm M138 Modem
Product Manual
Swarm M138 Modem Product Manual
Revision 1.00
November 2021
© 2021 Swarm Technologies, Inc.

Legal Notices
This User Manual provides user information and is provided “as is.” Swarm Technologies and its affiliated
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responsibility for any typographical, technical, content or other inaccuracies in this User Manual. Swarm
reserves the right to revise this User Manual or withdraw it at any time without prior notice. You can find
the current version of this Swarm Modem User Manual at www.swarm.space.
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DISCLAIMER AND EXCLUSION SHALL APPLY EVEN IF THE EXPRESS LIMITED WARRANTY
PROVIDED IN THE LEGAL INFORMATION BOOKLET FAILS OF ITS ESSENTIAL PURPOSE.
FURTHER, THE LIMITED WARRANTY COVERS THE SWARM M138 MODEM (INCLUDING
HARDWARE, SOFTWARE AND/OR FIRMWARE) AND ACCESSORIES ONLY, AND NO WARRANTY IS
MADE AS TO USER INFORMATION AND/ OR COVERAGE, AVAILABILITY OR GRADE OF SERVICE
PROVIDED BY SWARM SEPARATELY FOR SWARM SATELLITE SERVICES.
IN NO EVENT SHALL SWARM BE LIABLE, WHETHER IN CONTRACT OR TORT OR ANY OTHER
LEGAL THEORY, INCLUDING WITHOUT LIMITATION STRICT LIABILITY, GROSS NEGLIGENCE OR
NEGLIGENCE, OR IMPLIED WARRANTY, FOR ANY DAMAGES IN EXCESS OF THE PURCHASE
PRICE OF THE SWARM M138 MODEM (INCLUDING HARDWARE, SOFTWARE AND/OR FIRMWARE)
AND/OR ACCESSORIES AND/OR THE COST OF SWARM SATELLITE SERVICES PROVIDED, NOR
SHALL SWARM BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
CONSEQUENTIAL, OR PUNITIVE DAMAGES OF ANY KIND, OR LOSS OF REVENUE OR PROFITS,
LOSS OF BUSINESS, LOSS OF PRIVACY, LOSS OF USE, LOSS OF TIME OR INCONVENIENCE,
LOSS OF INFORMATION OR DATA, SOFTWARE OR APPLICATIONS OR OTHER FINANCIAL LOSS
CAUSED BY THE SWARM MODEM-M138 (INCLUDING HARDWARE, SOFTWARE AND/ OR
FIRMWARE) AND/OR ACCESSORIES AND/OR THE SWARM SATELLITE SERVICES, OR ARISING
OUT OF OR IN CONNECTION WITH THE ABILITY OR INABILITY TO USE THE SWARM
MODEM-M138 (INCLUDING HARDWARE, SOFTWARE AND/OR FIRMWARE) AND/OR
ACCESSORIES AND/OR THE SWARM SATELLITE SERVICES , TO THE FULLEST EXTENT THESE
DAMAGES MAY BE DISCLAIMED BY LAW AND REGARDLESS OF WHETHER SWARM WAS
ADVISED OF THE POSSIBILITIES OF SUCH DAMAGES.
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This User Manual might refer to third party sources of information, hardware or software, products or
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SWARM MAKES NO REPRESENTATIONS, GUARANTEES OR WARRANTIES IN RELATION TO
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Intellectual Property, Trade Secret, Proprietary or Copyrighted Information
To protect Swarm proprietary and confidential information and/or trade secrets, this User Manual may
describe some aspects of Swarm technology in generalized terms. Swarm products may include
copyrighted Swarm and third party software. Any such copyrighted software contained in Swarm products
may not be modified, reverse engineered, distributed or reproduced in any manner to the extent provided
by law. The purchase of any Swarm products shall not be deemed to grant either directly or by implication
or otherwise, any license under copyrights, patents, or patent applications of Swarm or any third party
software provider, except for the normal, nonexclusive, royalty free license to use that arises by operation
of law in the sale of a product.
Content Copyright
You are exclusively responsible for the use of the Swarm Modem-M138, including proper use of third
party copyrighted materials. If you violate these terms you agree to defend, indemnify and hold Swarm
harmless with respect to any claims or actions by third parties related to your improper use of copyrighted
materials and to pay all costs, damages, fines and other amounts incurred by Swarm, or on its behalf, in
the defense of any such claims or actions.
Export Compliance
The Swarm Modem-M138 is controlled by the export laws and regulations of the United States of
America. The U.S. Government may restrict the export or re-export of this product to certain individuals
and/or destinations. For further information, contact the U.S. Department of Commerce, Bureau of
Industry and Security or visit www.bis.doc.gov
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Revision History
Revision
Date
Comment
1.00
11/11/21
Swarm M138 Modem Product Manual - Initial Release
Additional Resources:
Please visit our developer tools webpage for quickstart guides and other helpful resources:
https://swarm.space/developertool
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Revision History 4
Additional Resources: 4
1 Safety Information and Compliance 7
1.1 FCC Compliance 7
1.2 ISED Compliance 7
1.3 RF Exposure Guidance 7
1.4 EU RED Certification 8
1.5 Transceiver Regulatory Certification 8
2 Product Overview 9
3 Mechanical Specification 10
3.1 Modem Dimensions 10
3.2 Environmental 11
3.3 Moisture Sensitivity Level 11
4 Electrical Interfaces 12
4.1 User Host Device 12
4.2 Modem Pin Allocation 13
4.3 DC Power Interface 15
4.4 Power On/Off Control 18
4.5 Serial Data Interface 18
4.6 LED Indicators 19
5 Design Guidance 20
5.1 Input Connections 20
5.2 Decoupling and Feed-through Capacitors 20
5.3 Input Voltage Examples 21
5.4 Communications 23
5.4.1 Level Shifting 24
5.5 Example Design 25
6 RF Interfaces 27
6.1 RF Connectors 27
6.2 RF Antenna 27
6.2.1 Antenna Characteristics 28
6.2.2 Ground Plane Requirements 29
6.3 Antenna Debugging 31
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7 Software interface 32
Message types 32
General command structure 32
Command timing 33
Command responses 33
Boot-up sequence 33
GPS Date/Time Reference 33
Messages 34
Table of Commands 35
$CS - Configuration Settings 36
$DT - Date/Time 37
$FV - Firmware Version 40
$GJ - GPS Jamming/Spoofing Indication 41
$GN - Geospatial information 43
$GP - GPIO1 Control 46
$GS - GPS Fix Quality 49
$MM - Messages Received Management 52
$MT - Messages to Transmit Management 56
$PO - Power Off 59
$PW - Power Status 60
$RD - Receive Data Message 62
$RS - Restart Device 63
$RT - Receive Test 64
$SL - Sleep mode 67
$M138 - Modem Status 70
$TD - Transmit data 71
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1 Safety Information and Compliance
The Swarm M138 Modem is designed to comply with the standards for Radio Emissions
Compliance and Electromagnetic Compatibility in the United States, Canada, Australia, New
Zealand, United Kingdom, European Union, Brazil, as well as worldwide.
1.1 FCC Compliance
Currently under review
1.1.4 FCC ID:
The Swarm Modem is currently under test and will receive FCC ID at a later date.
1.2 ISED Compliance
Currently under review
1.2.2 IC ID:
The Swarm Modem is currently under test and will receive IC ID at a later date.
1.3 RF Exposure Guidance
Currently under review
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1.4 EU RED Certification
1.4.1 Declaration of Conformity:
Currently under review
1.4.2 Article 10(2)/(10):
Currently under review
1.5 Transceiver Regulatory Certification
The Swarm Modem is a regulatory approved modular transmitter that is designed to be
integrated into an enclosed host system. With appropriate external connections, the host can be
designed to meet full regulatory tests and sold as a regulatory certified product that meets FCC,
IC, and CE requirements. Table 1 below is a partial list of regulatory approvals.
Regulatory
Approvals
Radio Tests
EMC Tests
Safety Tests
FCC
Currently under review
IC
Currently under review
CE
Currently under review
Table 1: Overview of the Swarm M138 Modem regulatory approvals.
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2 Product Overview
The Swarm Modem (Model: M138) satellite data modem transmits and receives data to and
from Swarm’s space network and is designed to be embedded into a third-party product. Swarm
backend systems support the delivery of customer data via a REST API or Webhook to the
cloud service of each user’s choice.
The Swarm Modem is a module suitable for a variety of low-bandwidth use cases: from
connecting people and tracking vehicles, ships, or packages to relaying sensor data for
agriculture, energy, and industrial IoT applications.
The Swarm Modem is a Mini-PCI Express Card that can be easily integrated into any new or
existing PCB design. The Swarm Modem communicates via a standard 3.3V CMOS serial
UART interface or a PC interface with a USB-to-serial converter.
Category
Description
Components
GPS, VHF radio with integrated T/R switch, U.FL connector for GPS and
VHF antenna, indicator LEDs, 3.3V serial interface, 3.3V GPIO, 1PPS GPS
Onboard
Sensors
uBLOX GPS (lat/lon/alt), 1 pulse per second signal
Dimensions
and Mass
51.0 mm x 30.0 mm x 5.3 mm, 9.6 g
See detailed description in the Mechanical Specification section.
Power
Mode
Typical
Peak
3.3V
5V
3.3V
5V
Sleep
-
-
70μA
110μA
Receiver Active
26mA
25mA
40mA
42mA
Transmitter On
1275mA
785mA
1600mA
790mA
Protocol
Modified NMEA two-letter command set
Bit rate
1 kbps. Maximum packet size is 192 bytes
Table 2: Overview of the Swarm Modem.
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3 Mechanical Specification
3.1 Modem Dimensions
The overall dimensions of the Modem and its weight are summarized in Table 3.
Parameter
Value
Length
51.0 mm
Width
30.0 mm
Height
5.3 ±0.1 mm
Weight
9.6 g
Table 3: Modem Mechanical Dimensions and Weight.
Figure 1: Modem front and back views.
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3.2 Environmental
The environmental specifications of the Modem are summarized in Table 4 below. The Swarm
Modem is not conformally coated, and as such the user needs to provide any weatherproofing
for their application.
Parameter
Value
Operating Temperature Range
-40 °C to +85 °C
Storage Temperature Range
-40 °C to +85 °C
Operating Humidity Range
0% to 95%, non-condensing
Storage Humidity Range
0% to 95%, non-condensing
Table 4: Environmental Specifications.
3.3 Moisture Sensitivity Level
The Modem is classified as an MSL 3 device as defined by IPC/JEDEC J-STD-020E standards.
Commercial Modem orders will be shipped in a moisture barrier antistatic bag or shrink wrap
with a desiccant and a moisture indicator card, along with a handling reference label.
Moisture Sensitivity Level
Floor Life
Time
Condition
3
168 Hours
≤30ºC/ 60%RH
Table 5: Modem MSL Specifications per IPC/JEDEC J-STD-020E
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4 Electrical Interfaces
The following subsections contain information for the electrical interfaces of the Modem.
4.1 User Host Device
The user host device provides the following connections to the Modem:
● DC power supply input: 3.0V to 5.5V, (1600 mApeak at 3.3V)
○ EMI/RFI shielding CAN is required if using a switching DC power supply in order
to contain radiated emissions
○ Additional filtering of the power supply is highly recommended
■ See Design Guidance for best practices
● Data interface
○ 3.3V Serial Data Interface
● Satellite signal (Use the provided U.FL connector labeled VHF)
● GPS signal (Use the provided U.FL connector labeled GPS)
● GPIO1 (optional)
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4.2 Modem Pin Allocation
The pin numbering scheme of the Swarm Modem is shown in Figure 4. All pins are located on
the card edge of the Swarm Modem and are designed to fit in a standard mPCIE card
connector. The pin function assignment is given in Tables 7 and 8. Multiple supply grounds are
provided and all power pins / supply grounds are required to be connected to the power supply
in order to limit the current on any one pin. Multiple signal grounds are provided to reduce
cross-talk. Many pins are intentionally left empty, and must be left unconnected.
Figure 4: Modem pinout and pin number
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Pin Number
Name
Type
Description
1,3,5-8,10,12,
14,16,19-20,
22-25,28,30,32,3
3,36,38,44-51
NC
NC
No Connection
2,39,41,52
VDD
Power
3.3V/5V at up to 1600mA/790mA
4,9,15,18,21,26,
27,29,34,35,37,
40,43,50
GND
Ground
Ground
11
UART_RX
Comms
3.3V serial receive
13
UART_TX
Comms
3.3V serial transmit
17
T/R OUTPUT
Digital Output
Transmit/Receive indicator
*leave open if not used
31
1PPS*
Digital Output
1 pulse per second
*leave open if not used
42
GPIO1
Digital Output
General purpose input/output
Table 7: Modem pin numbers and descriptions.
Additional Notes
Pin Number
Note
42
Connection is unbuffered and connected directly to a GPIO on the Modem
processor. Configuration will be provided via serial commands. GPIO1 pin
is 3.3V tolerant and open drain, with a sink current limit of 8 mA (20 mA
with a relaxed VOL/VOH)
2, 39, 41, 52
The VDD connection points are in parallel with one another and power the
Modem. If the designer wants to enable a complete power off mode, a load
switch can be provided here
31
The 1PPS signal is a one pulse per second signal synchronised with GPS.
*leave open if not used
17
HIGH when transmitting
LOW when receiving
*leave open if not used
Table 8: Additional notes on pin numbers.
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4.3 DC Power Interface
The DC power interface consists of the DC power inputs as summarized in Table 9. The power
requirements apply to DC power measured at the Swarm Modem user connector input and not
at the output of the power supply. It is required that users incorporate the required bypass
capacitors for the supplied power input as can be seen in Design Guidance.
Name
Description
Min
Typ
Max
Unit
VCC
Module supply voltage
3.00
3.30
5.50
V
VCC Ripple
Module supply voltage ripple
-
-
75
mVpp
VCC Limits
Module supply voltage absolute limits
3.00
-
5.50
V
ICC (3.3V)
Current consumption - Sleep Mode
-
-
70
μA
Current consumption - Receiver Active
23
26
40
mA
Current consumption - GPS Acquisition Mode*
40
46
57
mA
Current consumption - Transmitter on
1250
1275
1600
mA
ICC (4.2V)
Current consumption - Sleep Mode
-
-
120
μA
Current consumption - Receiver Active
23
25
40
mA
Current consumption - GPS Acquisition Mode*
41
47
60
mA
Current consumption - Transmitter on
930
940
970
mA
ICC (5.0V)
Current consumption - Sleep Mode
-
-
110
μA
Current consumption - Receiver Active
23
25
42
mA
Current consumption - GPS Acquisition Mode*
40
46
54
mA
Current consumption - Transmitter on
780
785
790
mA
Table 9: Power supply characteristics for 3.3, 4.2, and 5.0V supplies to the Modem.
*Includes satellite receiver active current with GPS in acquisition mode. The Modem enters into GPS acquisition
mode for approximately 30 seconds after exiting from sleep mode, on powerup, or when the Modem needs to
re-acquire a GPS fix (approximately once every 3 hours) while the Modem is continuously powered on and not in
sleep mode.
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An example power profile for a Modem powered with 3.3V can be found below in Figure 5.
Figure 5: Example current use for a Modem with a 3.3 V input from wake-up, GPS acquisition, Transmit, Receive
mode, and then sleep mode. Note the two breaks in the y-axis scale.
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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
4.3
mW-hrs
(15.6 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 10: 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 in Table 11:
Parameter
Value
Maximum power at antenna connector
1.122 W
Sum total of all capacitance
111 μF
Sum total of all inductance
1901 nH
Largest capacitor
47 μF
Largest inductor
1000 nH
Total Input Capacitance
57 μF
Table 11: Other electrical characteristics for the Modem
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4.4 Power On/Off Control
The Modem can be powered down with the use of the $PO*1F command. Once powered down,
it can be externally switched on/off by a user-supplied load switch on the VDD power rail.
After power to the Modem has been removed, power should not be restored until at least 1
second has elapsed.
If a Modem does not respond to software commands, remove power from the module, wait for
at least 1 second, and then power it back on. If the 1 second minimum wait time is not adhered
to, the reset circuit may not operate and the Modem could be placed in a non-operational state.
The state is not permanent and can be rectified by the above procedure.
4.5 Serial Data Interface
The serial data interface is a CMOS serial UART 3-wire (serial Rx, serial Tx, and ground)
interface at 3.3V digital signal levels over which the Modem transfers commands, responses,
and message data. The serial communication parameters can be found in Table 12.
Parameter
Value
Baud Rate
115200
Data Bits
8 Bits
Parity
None
Stop bits
1 Bit
Flow Control
None
Table 12: Serial communication parameters.
In addition, the electrical characteristics for SERIAL_RX, SERIAL_TX, and GPIO1 can be found
in Table 13.
Symbol
Parameter
Min
Typ.
Max
Unit
VIL
I/O input low level voltage
-0.3
-
0.3*3.3V
V
VIH
I/O input high level voltage
0.7*3.3V
-
3.3V
V
RPU/RPD
Weak pull up/down equivalent resistor
(for GPIO1)
25
40
55
kΩ
Table 13: Electrical characteristics for SERIAL_RX, SERIAL_TX, and GPIO1.
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All customer messages, data, and settings are stored in non-volatile memory. As such, after a
power cycle, customer settings as well as any messages that have not yet been transmitted
over the Swarm network will be retained on the Modem. The read/write lifetime of the Modem
memory exceeds 20 years.
4.6 LED Indicators
The Modem contains three indicator LEDs, whose function is described below in Table 14. All
LEDs are off when the Modem is placed into sleep mode.
LED
Function
Green
During the bootup sequence the green LED will be on solid for 3 seconds.
During normal operation after bootup and before shutdown, the green LED will blink
100ms every 5 seconds while the Modem is powered on. This is a “heartbeat”
indication that the Modem is working as expected.
Red
After power is applied until the Modem begins booting, the red LED will be on solid.
After bootup and while the Modem is acquiring a GPS fix, the red LED will flash
quickly until a valid GPS fix has been found. Then the red LED will shut off during
normal operation.
After waking up from sleep, and before a fresh GPS fix has been acquired, there
will be a single red LED flash every 5 seconds (following the green LED flash) until
a fresh GPS fix has been found. Then the red LED will again shut off during normal
operation.
During the shutdown sequence, the red LED will be on solid until 3.3V power is
removed from the board.
Blue
The blue LED will be on solid when the Modem is actively receiving from a Swarm
satellite
Table 14: LED functions.
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5 Design Guidance
This section describes the recommended design practices for successful integration of the
Modem.
5.1 Input Connections
The Swarm Modem utilizes standard 51 mm x 30 mm mPCIe form factors that require an
industry standard connector listed below. All voltage pins need to be connected in such a way to
minimize ground loops, often down by using a via to a power/ground plane. A method of
retaining the Modem is also required, whether it be a retaining clip or screws.
Below are example connectors, retaining clips, and their part numbers. Many vendors and
styles exist from vendors such as DigiKey/Mouser/Newark.
Example Connectors
Example Retaining Clips
JAE: MM60-52B1-B1-R850
JAE: MM60-EZH039-B5-R850
TE Connectivity: 2041119-2
TE Connectivity: 1717832-2
Altium footprints with correct connector/retaining clip spacing can be found in our Developer
Tools .
5.2 Decoupling and Feed-through Capacitors
We require a minimum amount of decoupling capacitance in order to reduce/eliminate any high
frequencies from the input supply reaching the Modem input terminals.
Choose Ceramic capacitors rated for 16V or greater, X5R or better
Qty
Size
1
100 nF
1
10 μF
2
100 μF
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