Myriota Module M2-
24
Maker’s Guide
MYRIOTA-TEC-179
26 February 2021
©Myriota Pty Ltd
Revision History
Rev
Date
Description of Change
1.0
1.1
February 2021
Initial version
February 2021
Updated with celltech Suggestions
Related Documentation
Find the latest versions of all Myriota documentation at developer.myriota.com
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MYRIOTA-TEC-179-1.1
Disclaimer
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is acting) (“You” and “Your”) by Myriota Pty Ltd for information purposes only.
— Information in this document is provided solely to enable system and software
implementers to use Myriota Pty Ltd products.
— Myriota Pty Ltd reserves the right to make changes without further notice to any products
herein.
— You are responsible for making Your own assessments concerning the Information and
Myriota recommends that You assess the accuracy, completeness and relevance of the
Information for Your purposes before using or relying on any of the Information.
— Myriota is providing the Information to you “AS IS” and without regard to Your specific
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not warrant the accuracy, completeness or relevance of the Information and accepts no
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— For further information, see myriota.com or contact your Myriota sales representative.
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MYRIOTA-TEC-179-1.1
Inter-Integrated Circuit Interface (I2C)
Universal Asynchronous Receiver/Transmitter (UART)
Serial Peripheral Interface (SPI)
Low Energy Universal Asynchronous Receiver/Transmitter (LEUART)
Table of Contents
1 - System Overview
1.1 - Features
Exceptional Battery Life
ARM Cortex-M4 core
Pulse Counter (PCNT)
Analog to Digital Converter (ADC)
Pre-Programmed UART Bootloader
1.2 - Safety and Compliance
1.2.1 - FCC Compliance
1.2.2 - Industry Canada Compliance
English
French
1.2.3 – Host Integration Compliance
2 - Physical Specification
2.1 - Module Dimensions and Layout
2.3 - Handling Information
2.4 - Soldering Information
2.5 - PCB Layout Considerations
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MYRIOTA-TEC-179-1.1
2.6 - General Environmental Characteristics
3 - Electrical Information
Typical Values
Absolute Maximum Ratings
3.1 - Block Diagram
3.2 - Module Pin Assignment
3.3 - Power Consumption
3.4 - Electrical Specifications
Table 5: General Operating Conditions
Table 6: General Purpose Input Output
Table 7: Analog Digital Converter (ADC)
Table 8: I2C
Table 9: Temperature Sensor
Table 10: Test Conditions
4 - Radio Elements
4.1 Operational Frequencies
4.2 - Antenna Connection
4.3 - Antenna Integration
General considerations
4.4 - Antenna Requirements
UHF Transmit & Receive
Requirement
Example Use Case
4.4 - RF Characteristics
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4.5 - GNSS (Global Navigation Satellite System)
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MYRIOTA-TEC-179-1.1
5 - Getting Started
Visit the Myriota Developer Site
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MYRIOTA-TEC-179-1.1
1 - System Overview
The Myriota M2-24 Module (“the Module”) employs smart power features and onboard edge
computing, combined with the super low bandwidth Myriota Network, to provide an ideal IoT
communications solution for remote devices.
1.1 - Features
Exceptional Battery Life
minimum power
ARM Cortex-M4 core
MIPS/MHz
— The Module predicts the location of satellites in the Myriota constellation, waking to
transmit and receive only when a satellite is overhead
— Intelligent scheduling and specially designed radio waveforms ensure reliable delivery at
— Energy efficient ARM Cortex-M4 with 32-bit RISC processor capable of 1.25 Dhrystone
Inter-Integrated Circuit Interface (I2C)
— The Module acts as a master, and supports standard-mode, fast-mode and fast-mode
plus speeds
Universal Asynchronous Receiver/Transmitter (UART)
— The Universal Asynchronous serial Receiver and Transmitter (UART) supports full- and
half-duplex asynchronous UART communication. One UART supports hardware flow
control
Serial Peripheral Interface (SPI)
to 24MHz
— The Serial Peripheral Interface (SPI) acts as a master, and supports clock data rates up
Low Energy Universal Asynchronous Receiver/Transmitter (LEUART)
— The Low Energy UART enables two-way communication on a strict power budget. Only a
32.768 kHz clock is needed to allow UART communication up to 9600 baud/s
— The LEUART makes asynchronous serial communication possible with minimal software
and energy consumption. The LEUART can wake the Module from sleep mode
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MYRIOTA-TEC-179-1.1
Pulse Counter (PCNT)
— The Pulse Counter (PCNT) can be used for counting pulses on an input while the Module
is in sleep mode. It can also wake up the Module from sleep mode when a prespecified
number of pulses have been counted
Analog to Digital Converter (ADC)
— 12-bit ADC supporting VIO_REF, 2.5V or 1.25V as reference voltages
Pre-Programmed UART Bootloader
— The pre-programmed bootloader can be used to program the flash, retrieve Module
information and dump logs
1.2 - Safety and Compliance
1.2.1 - FCC Compliance
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two
conditions:
1. This device may not cause harmful interference, and
2. This device must accept any interference received, including interference that may cause
undesired operation.
● This equipment complies with FCC radiation exposure limits set forth for an uncontrolled
environment. End users must follow the specific operating instructions for satisfying RF
exposure compliance. This transmitter must not be co-located or operating in conjunction
with any other antenna or transmitter.
● Changes or modifications not expressly approved by the party responsible for compliance
could void the user's authority to operate the equipment.
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MYRIOTA-TEC-179-1.1
1.2.2 - Industry Canada Compliance
English
Under Industry Canada regulations, this radio transmitter may only operate using an antenna of
a type and maximum (or lesser) gain approved for the transmitter by Industry Canada. To reduce
potential radio interference to other users, the antenna type and its gain should be so chosen that
the equivalent isotropically radiated power (e.i.r.p.) is not more than that necessary for successful
communication. This device complies with Industry Canada license-exempt RSS standard(s).
Operation is subject to the following two conditions: (1) this device may not cause interference,
and (2) this device must accept any interference, including interference that may cause undesired
operation of the device.
French
Conformément à la réglementation d'Industrie Canada, le présent émetteur radio peut fonctionner
avec une antenne d'un type et d'un gain maximal (ou inférieur) approuvé pour l'émetteur par
Industrie Canada. Dans le but de réduire les risques de brouillage radioélectrique à l'intention des
autres utilisateurs, il faut choisir le type d'antenne et son gain de sorte que la puissance isotrope
rayonnée équivalente (p.i.r.e.) ne dépasse pas l'intensité nécessaire à l'établissement d'une
communication satisfaisante. Le présent appareil est conforme aux CNR d'Industrie Canada
applicables aux appareils radio exempts de licence. L'exploitation est autorisée aux deux
conditions suivantes : (1) l'appareil ne doit pas produire de brouillage, et (2) l'utilisateur de
l'appareil
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MYRIOTA-TEC-179-1.1
1.2.3 – Host Integration Compliance
2.2 This device was evaluated to, and complies with, FCC 47 CFR Part 25 Subpart C and
ISED RSS-170
2.3 This device shall only be used in the manner intended to be used and in accordance
with FCC 47 CFR Part 25 Subpart C and ISED RSS-170.
2.4 This device is certified as an FCC Single Modular Approval and ISED Modular
Approval (MA)
2.5 See Section 2.5 for trace design considerations
2.6(1) This device is approved for use with mobile and fixed applications. The antenna(s)
used for this transmitter must be installed to provide a separation distance of at least 20cm
from all persons.
2.6(2) The Host manufacturer is required to provide the above information to the end user
in their end-product manuals, except in accordance with the FCC and ISED change
procedures.
2.7. This device is approved for mono-pole, folded mono-pole, normal-mode helix, folded,
normal-mode helix, and loaded monopole antennas with a gain of 6dBi or less and must
not transmit simultaneously with any other antenna or transmitter, except in accordance
with FCC and ISED multi-transmitter product procedures. Use of any other antenna type
or antenna gain exceeding 6dBi violates the conditions for which it was approved.
2.8 The Host manufacturer is required to identify the FCC ID and IC ID of this module on
their host device, either a physical label or e-label, for example:
“Contains FCC ID: 2ATKL-M2-24”
“Contains IC ID: 25148L-M224”
2.9 Contact Myriota for Test-mode software options.
2.10 Approval is limited to OEM installation only. This device shall only be used in the
manner intended to be used and in accordance with FCC 47 CFR Part 25 Subpart C and
ISED RSS-170. Compliance of this device in all final host configurations is the
responsibility of the Host Grantee. The Host manufacturer is responsible for compliance
to any other FCC and ISED rules that apply to the Host that are not covered by the modular
transmitter grant of certification. Additional guidance for testing host products is given in
KDB Publication 996369 D04 Module Integration Guide and RSS-Gen.
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2 - Physical Specification
The Myriota M2-24 Module is designed to, and must be installed within an enclosed host system.
With appropriate external connections, the host system and host system enclosure can be
designed to meet full transceiver regulatory tests.
2.1 - Module Dimensions and Layout
The Myriota M2-24 Module dimensions and weight are outlined in Table 1, and in Figure 1 for
illustrative purposes.
Table 1: M2-24 Module Dimensions and Approximate Weight
Length
Width
Depth
Weight (appox.)
Figure 1: PCB Land Pattern
33.91 mm
20.90 mm
3.98 mm
4 g
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MYRIOTA-TEC-179-1.1
2.3 - Handling Information
Moisture Sensitivity Level (MSL): 3 per IPC/JEDEC standard J-STD-020.
Avoid washing as moisture can be trapped under the shield.
Electrostatic Discharge Caution: The module contains static-sensitive components and should
be handled with care.
The following precautions are recommended to avoid static damage.
● Avoid touching pins. Always hold modules by its edges
● Handle modules in areas with adequate grounding
● Keep modules in trays/ESD bags until ready for assembly
2.4 - Soldering Information
The Myriota M2-24 is designed to be soldered in accordance with the latest IPC/JEDEC J-STD-
020 recommendations for Pb-Free ánd Sn-Pb reflow soldering.
Follow the standard recommendations to avoid damage to the modules:
● Do not exceed peak temperature (Tp) of 250ºC
● Use solder paste with no clean flux
● Refer to solder paste datasheet for reflow profiles
● Avoid multiple reflows. For multiple reflow processes, solder module on the last reflow.
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MYRIOTA-TEC-179-1.1
2.5 - PCB Layout Considerations
● The PCB trace connecting the Myriota Module’s RF PORT to the antenna needs to be a
controlled impedance, 50-ohm transmission line. Microstrip is recommended, but other
types of transmission lines would be acceptable, depending on the trade-offs that are
most important for a given application.
● The exact geometries of the 50-ohm microstrip depend on the characteristics of the PCB
substrate that is being used in the application, i.e. laminate dielectric constant and
thickness, copper weight/thickness, etc. Numerous online transmission line calculators
are available that will be able to provide you with an estimate of the required microstrip
geometries. The PCB fabrication house that you work with should be able to provide
accurate microstrip geometries for your specific implementation.
● Use of multi-layer PCB is recommended for the application PCB. Multiple layers allow for
a continuous RF reference (i.e. ground) plane to be provided underneath the Myriota
Module, the RF interface between the Myriota Module’s RF Port and the antenna.
●
●
It is recommended that the PCB stack-up be arranged in a manner that places the RF
reference ground plane on the internal copper layer adjacent to the layer in which the
Myriota Module is mounted.
It is desirable that the PCB stack-up be designed so that the laminate thickness between
the internal RF reference plane and the microstrip traces on the outer layer realizes a
microstrip trace width that is similar to the pad width of the size of the discrete
components used. (i.e. 0402, 0603, etc.) Doing so will minimize the width transitions
between the microstrip and component pads, thus keeping impedance anomalies to a
minimum.
● For most applications, it should be possible to provide a functional PCB layout with a 4-
or 6-layer PCB. For extremely cost-sensitive applications, it may be possible to use a 2-
layer PCB, but it is not recommended.
● The RF port and antenna should be placed in a region of the PCB that is furthest away
from possible noise sources on the application PCB. (i.e. clocks, digital buses, switching
power supplies, etc.)
● Do not route any noise signal or power traces near the RF Port to Antenna interface
region.
● The RF Port of the Myriota Module should be placed as close to the antenna as is
practical to minimize RF signal losses.
●
If using a multi-layer PCB, it is advisable to bury noisy signal or power traces on internal
layers of the PCB and sandwich them between solid GND planes to provide shielding.
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MYRIOTA-TEC-179-1.1
● Ground pads of the Myriota Module should be connected directly to the ground
reference plane with the ground vias placed as close to the Myriota Module pads as is
practical.
● Power supplied to the Myriota Module should be clean and isolated from potential noise
sources originating from the application circuitry. This can be achieved through the use
of filters or linear regulation in the power feed to the Myriota Module.
● The power source supplying the Myriota Module must have sufficient current sourcing
capability to satisfy the Myriota Module's maximum specified current draw, as specified
in the Myriota Module Data Sheet, plus some additional margin for good design practice.
● On the same layer that the Myriota Module is mounted, do not place any copper (i.e.
traces, vias, pours) in the Copper Keepout Region. It is however recommended to place
an RF ground reference plane underneath the Myriota Module on the next adjacent layer
of the PCB.
● Make sure that the antenna that you have selected is nominally matched to 50-ohms at
the frequency band that the Myriota Module is operating. If you are not certain how to do
this, seek design assistance from an RF or antenna design engineer. A good antenna
match is critical to the performance of the Myriota Module’s transceiver and should not
be overlooked.
●
If the radio contains multiple transceivers or receivers that could potentially be active at
the same time, make sure to space their antennas as far apart as is practical in order to
minimize the coupling between antenna elements. To further mitigate interference
between these radio devices, RF filtering and shielding should be considered to mitigate
unwanted signals in the frequency bands of interest.
2.6 - General Environmental Characteristics
Table 2: General Environmental Characteristics.
Parameter
Minimum
Typical
Maximum
Unit
Operating temperature
Storage temperature
-30
-55
-
-
70
150
ºC
ºC
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MYRIOTA-TEC-179-1.1
3 - Electrical Information
Typical Values
The typical data are based on ambient temperature TAMB = 25°C and power supply voltage
VEXT = 3.6 V.
Absolute Maximum Ratings
The absolute maximum ratings are stress ratings, and functional operations under such
conditions are not guaranteed. Stress beyond the limits specified in the table below may affect
device reliability or cause permanent damage to the device.
3.1 - Block Diagram
Figure 2: A simplified block diagram of the Myriota Mx-2x series.
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MYRIOTA-TEC-179-1.1
3.2 - Module Pin Assignment
The Myriota M2-24 Module features 58 pins, as depicted in Figure XX, and Table XX.
Figure 3: M2-24 Module Pin Assignment
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MYRIOTA-TEC-179-1.1
Table 3: Pin Descriptions
Number
Name
Description / Alternative Functionality
VIO_REF
Voltage reference output for all external devices
BAND
Read-only, do not connect. High on M1 variant and low on M2 variant
GND
VEXT
GND
ADC1
GND
ADC0
GND
NRST
GPIO2
GPIO3
GND
RF_EN
Ground
Power supply
Ground
ADC port 1. GPIO
Ground
Ground
ADC port 0. GPIO
GPIO
GPIO
Ground
PULSE1
Pulse counter. GPIO
PULSE0
Pulse counter. GPIO
UART0_RTS
UART0 RTS. GPIO
Reset input, active low. Drive NRST low to reset. An internal pull-up
ensures that NRST is released
Output only. High when radio is enabled and low when radio is
disabled
GND
Ground
SPI_CS
SPI chip select. GPIO
SPI_SCK
SPI SCLK. GPIO
SPI_MISO
SPI MISO. GPIO
SPI_MOSI
SPI MOSI. GPIO
RF_TEST1
Reserved, do not connect
GPIO0_WKUP GPIO. Can wake the Module from sleep mode
GND
Ground
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MYRIOTA-TEC-179-1.1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
GND
Ground
RF_PORT
RF port for both input and output
RF_TEST2
Reserved, do not connect
GND
GND
GND
GND
GPIO4
GPIO5
GPIO6
GND
GND
GND
GND
Ground
Ground
Ground
Ground
GPIO
GPIO
GPIO
Ground
Ground
Ground
Ground
VUSB
USB 5.0 V VBUS input. Reserved, do not connect
GPIO1_WKUP GPIO. Can wake up the Module from sleep mode
SWDIO
Debug-interface Serial Wire data input / output with built-in pull up
SWCLK
Debug-interface Serial Wire clock input with built-in pull down
GND
Ground
USB_D_P
USB D+ pin. Reserved, do not connect
USB_D_N
USB D- pin. Reserved, do not connect
GND
Ground
UART1_RX
UART1 RX, input. GPIO
UART1_TX
UART1 TX, output. GPIO
I2C_SCL
I2C_SDA
I2C SCL with built-in 2.2kOhm pull up. External pull up is not
recommended
I2C SDA with built-in 2.2kOhm pull up. External pull up is not
recommended
GPIO8
GPIO
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MYRIOTA-TEC-179-1.1
53
54
55
56
57
58
Mode
Sleep
Receive
Transmit
GPIO7
GPIO
UART0_CTS
UART0 CTS. GPIO
UART0_TX
UART0 TX, output. Bootloader TX
UART0_RX
UART0 RX, input. Bootloader RX
LEUART_RX
LEUART RX, input
LEUART_TX
LEUART TX, output
3.3 - Power Consumption
The Module is designed with a very low power consumption profile, and is designed to attain
multi-year battery life with two “AA'' battery cells. Table XX lays out the power consumption for
the Module.
Table 4: Specific average power consumption measured at 25ºC
Sleep with Pulse Counter enabled
1.9
Sleep with LEUART enabled
2.0
MCU Processing
3.3V
1.5
2.0
2.1
19
35
3.6V
1.6
2.1
2.2
17
32
Unit
uA
uA
uA
mA
mA
mA
640
570
510
3V
1.4
22
37
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3.4 - Electrical Specifications
The electrical parameters for the Module are detailed in the tables below.
Table 5: General Operating Conditions
Parameter
Minimum
Typical
Maximum
Unit
Operating temperature
-30
Clock frequency
VEXT
VIO_REF (non sleep mode)
3.3
VIO_REF (sleep mode)
VEXT-0.2
70
48
3.6
-
-
VIO_REF output current
100
mA
Table 6: General Purpose Input Output
Parameter
Minimum
Typical
Maximum
Unit
-
-
-
-
-
-
±0.1
40
40
3.0
-
-
-
-
-
-
-
-
0.7 VIO_REF
0.8 VIO_REF
ºC
MHz
V
V
V
V
V
nA
kOhm
kOhm
0.30 VIO_REF V
0.25 VIO_REF V
±100
-
-
-
-
Input low voltage
Input high voltage
Output high voltage
Output low voltage
Input leakage current
I/O pin pull-up resistor
I/O pin pull-down resistor
Table 7: Analog Digital Converter (ADC)
Parameter
Minimum
Typical
Maximum
Unit
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MYRIOTA-TEC-179-1.1
Input voltage range
Resolution
Input capacitance
Input ON resistance
Input RC filter resistance
Input RC filter/decoupling
capacitance
ADC Clock Frequency
Conversion and acquisition time
87
non-linearity (INL)
Offset voltage
-3.5
0
-
-
1
-
-
-
-
Table 8: I2C
Parameter
SCL clock frequency
SCL clock low time
SCL clock high time
SDA set-up time
SDA hold time
Repeated START condition set-up time
(Repeated) START condition hold time
STOP condition set-up time
Bus free time between a STOP and a START
condition
Table 9: Temperature Sensor
Reference voltage V
-
-
-
-
-
3
-
±3
3
-
-
-
-
-
-
-
-
-
bit
pF
MOhm
kOhm
fF
MHz
ADCCLK
Cycles
LSB
mV
3450
-
-
-
-
-
-
-
us
us
ns
ns
us
us
us
us
Minimum Typical
Maximum Unit
100
kHz
12
-
2
-
10
13
-
250
±1.2
0.3
0
4.7
4.0
250
8
4.7
4.0
4.0
4.7
-
-
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Parameter
Minimum
Typical
Maximum
Unit
Measurement range
Accuracy
-30
± 2
+70
-
ºC
ºC
MYRIOTA-TEC-179-1.1
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MYRIOTA-TEC-179-1.1
Table 10: Test Conditions
Parameter
Minimum
Typical
Maximum
Unit
Storage temperature
External supply voltage (VEXT)
0
Voltage on any I/O pin
-55
-0.3
-
-
-
150
3.6
ºC
V
VIO_REF+0.3 V
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MYRIOTA-TEC-179-1.1
The Myriota M2-24 variant module transmits and receives on UHF. A single antenna can be used
to provide both channels.
4 - Radio Elements
4.1 Operational Frequencies
Table 11: Operational Frequencies.
Frequency
UHF Transmission
399.9 - 400.05 MHz
UHF Receive
400.15 - 401 MHz
4.2 - Antenna Connection
This Module has no integrated connector. All RF activity is operated over Pin 27. Methods by
which a temporary may be used for testing are detailed in Section 4.2, but by no means should
be integrated with a final product.
4.3 - Antenna Integration
General considerations
When integrating your antenna, the following guidelines should be followed to ensure the design
achieves the highest possible system performance.
● The sum of all losses from transmission lines or components in the signal path between
the module and an antenna must be less than 1 dB
● Keep transmission lines and cables as short as possible. The number of RF connectors
in the signal path should also be minimised.
● Minimise the length of micro-striplines on multi-layered or thin FR4 substrates. The
commonly used 3 mm wide track on a 1.6 mm FR4 substrate has 1.5 dB/m loss. In
comparison, a thinner 0.7 mm track, 0.36 mm substrate layer arrangement can have 2.5
dB/m. Avoid using PCB vias in the signal path.
●
If a matching network is required for the antenna use low-loss inductors or, if possible,
avoid inductors altogether. Inductors with high quality factor (Q), and low DC resistance
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MYRIOTA-TEC-179-1.1
(DCR) from Taiyo Yuden are a good choice. The inductor’s self resonant frequency (SRF)
should be higher than the operating frequency. An example of a 120 nH inductor is
HK1005R12J-T. Its specifications are: DCR=1.6 Ohm; Q=8 @ 100 MHz; SRF=600 MHz.
Q scales approximately by √f , so in this example the inductor would have a Q of about 16
at 400 MHz.
● Often an RF connector is added to assist testing or developing a PCB. In cases where the
RF connector is permanent, use of an inline-type connector eliminates the need for a 0R
resistor to switch the signal path. If a 0R resistor is used to switch the signal path to a test
RF connector, arrange the circuit such that the switch resistor is normally not loaded in
order to connect the module to an embedded antenna.
● Figure XX below shows an example use of a temporary RF connector which can be loaded
on the PCB as required. The component footprint could be one component of the matching
network of an embedded antenna, removed as required to isolate the embedded antenna.
In this way a series 0R resistor is eliminated in the signal path.
Figure 4: Example use of a temporary RF connector
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MYRIOTA-TEC-179-1.1
4.4 - Antenna Requirements
The following sections define the network requirements on both the transmit and receive antennas
for the M2-24 Myriota Module. The requirements are defined in terms of recommended antenna
gains, assuming the device has clear sky view in all directions.
An antenna that exceeds the recommended gain requirement will result in increased performance
of your device. Likewise, an antenna that has less gain will result in reduced device performance.
UHF Transmit & Receive
Requirement
A UHF antenna with a gain versus elevation pattern as shown below will result in the
recommended minimum signal strength at the ground receiver.
Elevation (deg.)
0
5
10
20
30
40
45
50
60
70 80 85
90
Required Gain (dBi)
-1
-2
-4
-7
-9
-11 -12 -12 -13 -14
-14
-14 -14
Figure 5 & Table 12: Required UHF Antenna Gain (dBi) vs Satellite Elevation (deg.)
Example Use Case
A second example shown in the graph below provides an analysis of the suitability of a UHF
antenna for both transmit and receive use on the Myriota Network. The gain of the example
antenna (dashed line) is plotted alongside the UHF antenna requirement (solid line).
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MYRIOTA-TEC-179-1.1
Comparing the gain of the antenna to the recommended minimum, you can see that it either
meets or exceeds the requirement at mid elevations, with diminished performance at high and
very low elevations. Again this is representative of the characteristics expected from an electrically
small monopole with vertical polarisation.
Depending on system requirements, the reduced performance at high and very low elevations
can be considered acceptable.
Elevation (deg.)
0
5
10
20
30
40
45
50
60
70 80 85
90
Example Gain (dBi)
-3
-3
-5
-6
-7
-9
-12
-18
-24 -38
Required Gain (dBi)
-1
-2
-11 -12 -12 -13 -14
-14
-14 -14
Margin (dB)
-2
-1
6
6
5
4
2
-4
-10 -24
-3
-4
1
-3
-7
4
-4
-9
5
Figure 6 & Table 13: Antenna Gain (dotted) vs UHF Antenna Requirement (solid)
27
MYRIOTA-TEC-179-1.1
4.4 - RF Characteristics
Table 14 lays out the RF characteristics of the Module.
Table 14: Radio Characteristics.
Parameter
Minimum
Typical
Maximum
Unit
Transmission duration
260
Transmission interval
UHF TX frequency
UHF RX frequency
LPD frequency
UHF output power
LPD output power
5
-
-
399.9
400.15
433
-
-
-
-
-
400.05
MHz
401
435
28
14
ms
s
MHz
MHz
dBm
dBm
4.5 - GNSS (Global Navigation Satellite System)
The Myriota Module requires an external GNSS device for normal operations. Currently, all
uBlox™ M8 chips are supported via UART1. The following figure shows an example of using
the SAM-M8Q-0-10 GNSS module1.
1 Datasheet Available here:
https://www.u-blox.com/sites/default/files/SAM-M8Q_DataSheet_%28UBX-16012619%29.pdf
28
MYRIOTA-TEC-179-1.1
Figure 15: The SAM-M8Q-0-10 GNSS module
The SAM-M8Q-0-10 module has a backup voltage supply (V_BCKP). When the power supply to
the module is off, V_BCKP supplies the real-time clock (RTC) and battery-backed RAM (BBR).
Use of valid time and the GNSS orbit data at start-up will improve the GNSS performance, i.e. hot
starts and warm starts.
If no backup battery is connected, the module performs a cold start at power-up. It is important to
note that connecting the V_BCKP pin to a permanent supply will consume an extra 15uA of sleep
current.
For a detailed description of integrating the GNSS module please refer to the SAM-M8Q
Hardware Integration Manual2.
2 Available Here:
https://www.u-blox.com/sites/default/files/SAM-M8Q_HardwareIntegrationManual_%28UBX-
16018358%29.pdf
29
MYRIOTA-TEC-179-1.1
5 - Getting Started
Visit the Myriota Developer Site
Once you are ready to begin developing the software for the Module, head over to the Myriot
Developer Site at: https://developer.myriota.com/
Figure XX: The Myriota Developer Site
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MYRIOTA-TEC-179-1.1