The ARGOS ARTIC R2 satellite communication chipset in Thing Plus format.
Dimensions are in inches 
The ARTIC-R2 is an integrated low power small size ARGOS 2/3/4 single chip radio. ARTIC-R2 implements a message based wireless interface. For satellite uplink communication, ARTIC-R2 will encode, modulate and transmit provided user messages. For downlink communication, ARTIC-R2 will lock to the downstream, demodulate and decode it and extract the satellite messages.
The ARTIC-R2 can transmit signals in frequency bands around 400MHz and receive signals in the bands around 466MHz, in accordance with the ARGOS satellite system specifications. The ARTIC-R2 is compliant to all ARGOS 3 and ARGOS 4 RX and TX standards. It contains a RF transceiver and frequency synthesizer and a digital baseband modem. The ARTIC-R2 contains an on-chip power amplifier delivering 1mW [0dBm] output power, that serves as an output for connecting an external high efficient PA. The (de)modulation algorithms run on an on-chip DSP. This software approach allows for retargeting the ARTIC for other applications. The DSP program can be retained on an external flash or the MCU.
- Serial interface (SPI) for communication with MCU
- Programmable DSP core on board to ensure flexibility
- RX frequency : 466MHz – TX frequency: 400MHz
- Fractional N frequency synthesis
- Supported TX standards:
- BPSK: PTT-A2 (ARGOS 2), PTT-VLD (ARGOS 4)
- QPSK: PTT-A3, PTT-ZE (ARGOS 3)
- GMSK: PTT-HD (ARGOS 3), PTT-MD (ARGOS 4), PTT-HD (ARGOS 4)
- Supported RX standards:
- BPSK: PMT-A3 (ARGOS 3)
- DSSS OQPSK: PMT-A4 (ARGOS 4) not available
- Dedicated flash Interface to retain Firmware
- Support COSPAS-SARSAT standard
- Operates on external 26MHz reference clock
- Dual supply, 1.8V and 3.3V
- Integrated PA (0dBm) to combine with external PA
An RFPA0133 programmable gain power amplifier boosts the 0dBm (1mW) output from the ARTIC by up to 26dB, producing a maximum transmit power level of 400mW. The transmit power can be adjusted via the G8 breakout pin.
The ARGOS satellite system is restricted to specific programs and applications. Please check that your project meets these requirements before buying hardware. CLS (France) and the Woods Hole Group (America) will be able to advise if your project meets the requirements.
- "To meet system use requirements, all programs using Argos have to be related in some way or other to environmental protection, awareness or study, or to protecting human life."
- CIPO: SPI interface: Controller In Peripheral Out. 3.3V.
- COPI: SPI interface: Controller Out Peripheral In. 3.3V.
- SCLK: SPI interface clock signal. Typically 1MHz. 3.3V. See the ARTIC R2 datasheet for the permitted clock speeds.
- CS: SPI interface Chip Select. 3.3V. Active low.
- GND: Power ground / 0V.
- G8: Pull up to 3.3V to set the RFPA0133 transmit power to maximum. The transmit power will be reduced by approximately 5dB if this pin is pulled low or left open.
- BOOT: Connected to the ARTIC BOOT pin. Pulled up to 3.3V via a 100k resistor. When high, the ARTIC boots from the on-board flash memory. Pull low if the ARTIC firmware will be downloaded by the MCU via SPI.
- INT1: Connected to the ARTIC INT1 pin. Will be pulled up to 3.3V by the ARTIC to indicate (e.g.) an RX_VALID_MESSAGE.
- INT2: Connected to the ARTIC INT2 pin. Will be pulled up to 3.3V by the ARTIC to indicate (e.g.) an RX_BUFFER_OVERFLOW.
- RESETB: Connected to the ARTIC reset pin. Pulled up to 3.3V via a 100k resistor. Pull low to reset the ARTIC.
- PWR EN: Pulled low via a 100k resistor. Pull up to 3.3V to enable power for the ARTIC R2.
- RF EN: Pulled low via a 100k resistor. Pull up to 3.3V to enable power for the RF amplifier.
- VUSB: Power input from (e.g.) USB. Typically 5V. 6.5V maximum.
- VBATT: Power input from (e.g.) a LiPo battery. Typically 3.6V - 4.2V. 6.5V maximum.
Power can be provided via the VBATT pin or the VUSB pin, or both. The shield will preferentially draw power from USB if connected. On-board 3.3V regulators regulate USB or battery power down to 3.3V for the ARTIC and RF amplifier. See below for the typical VUSB current draw.
The full schematic for the Satellite Transceiver Shield is available here.
- RF: RF amplifier power
- RX: ARTIC is receiving
- TX: ARTIC is transmitting
- PWR: ARTIC R2 power
The LEDs can be disabled to save power by cutting the jumper links on the bottom of the PCB.
The antenna is connected via a uFL connector. A 400MHz quarter wave wire antenna is all that is required for most applications.
Always ensure an antenna is attached to the transceiver shield. (Never attempt to transmit without an antenna attached! Doing so can damage the RF amplifier.)
The SparkFun ARGOS ARTIC R2 Arduino Library contains a full set of examples to get you up and running with the SparkX ARGOS Satellite Transceiver Shield.
The SparkX ARGOS Satellite Transceiver Shield is designed to interface directly to a SparkFun Thing Plus board. The examples in the Arduino library are written for the Thing Plus - Artemis but can be adapted to any board simply by changing the declared pin numbers.
You can mount the Satellite Transceiver Shield on a Thing Plus board using Break Away Headers - Straight on the ARTIC and Female Headers on the Thing Plus. That way you can remove the Transceiver Shield if you want to and perhaps mount the board on a Breadboard instead.
If you are new to Arduino and the IDE, these guides will get you up and running:
- Hookup Guide for the SparkFun Artemis Thing Plus
- Artemis Development with Arduino
- Installing an Arduino Library
In the Arduino IDE, please make sure you select the correct board. The examples in the Arduino library assume you will be using the SparkFun Artemis Thing Plus from the SparkFun Apollo3 boards package.
You can install the library using the IDE by opening Tools\Manage Libraries and then searching for SparkFun ARGOS ARTIC R2.
- Install the Arduino IDE
- Add the SparkFun Boards to the Preferences\Additional Board Manager URLs and install the SparkFun Apollo3 board package
- Close the IDE
- Install the CH340 COM port drivers
- Reopen the IDE
- Click on Tools\Board and select SparkFun Apollo3\SparkFun Artemis Thing Plus
- Click on Tools\Manage Libraries... to open the library manager
- In the search box, type SparkFun ARGOS ARTIC R2
- Click the Install button to install the ARGOS ARTIC R2 library
- Click on File\Examples. Hover over SparkFun ARGOS ARTIC R2 Library and select one of the examples
- Attach an antenna to the SparkX ARGOS Satellite Transceiver Shield. (Never attempt to transmit without an antenna attached!)
- Mount the Satellite Transceiver Shield onto the SparkFun Thing Plus Artemis
- Attach the Thing Plus to your computer using a USB-C cable
- Click on Tools\Port and select the COM port for the Artemis
- Click on the Upload button to upload the example onto the Artemis
- Open Tools\Serial Monitor to see the serial messages from the Artemis
- Check that the baud rate is set to 115200
- The two red LEDs on the Satellite Transceiver Shield will light up when the code is running
When powering the Artemis via USB-C or from a LiPo battery, it may not reset correctly when the power is connected. There are two easy ways to reset it:
- If you have the Arduino IDE open, opening the Serial Monitor will reset the Artemis
- If the Serial Monitor is already open, clicking 115200 in the Baud rate drop-down menu will also reset the Artemis
- Press the RST button next to the SparkFun flame logo, near the USB-C connector
The two red LEDs on the Satellite Transceiver Shield will light up to indicate that the Artemis has been reset and that the code is running
- Sleep: 51µA
- Idle: 7.2mA
- Receive: 32.8mA
- Transmit (G8 pin high): 220mA
- Transmit (G8 pin low): 170mA
- /Documents - Datasheets, test certificates etc.
- /Hardware - Eagle PCB, SCH and LBR design files
- LICENSE.md - contains the licence information
The SparkX ARGOS Satellite Transceiver Shield is a remix of the reference design kindly provided by the Arribada Initiative and Icoteq Ltd.