¶ Order Yours Today
| Store | URL | Description |
|---|---|---|
| Tindie | tindie.com | Our Official Store on Tindie |
| Official Store | shop.uniteng.com | Our Official Store, Secure Payments By PayPal, Volume Discount Available |
¶ Overview
The Station Edition is a compact and durable Lora device designed for high-performance radio frequency communication. It features a powerful PA for Lora communication, a rugged SMA antenna socket, and a variety of external IO interfaces. With a wide input voltage range, this device is suitable for both fixed and vehicle-mounted applications. The compact size and rugged construction make it an ideal choice for base stations in various scenarios.
For the firmware, all Station Series devices come with pre-installed Meshtastic. More detials could be found in the The Latest Firmware section.
Meshtastic Frequency Bands Supported by Station G2[1]:
US (902.0Mhz to 928.0Mhz), EU_868 (869.4Mhz to 869.65Mhz), JP (920.8Mhz to 927.8Mhz), ANZ (915.0Mhz to 928.0Mhz), RU (868.7Mhz to 869.2Mhz), KR (920.0Mhz to 923.0Mhz), TW (920.0Mhz to 925.0Mhz), IN (865.0Mhz to 867.0Mhz), NZ_865 (864.0Mhz to 868.0Mhz), TH (920.0Mhz to 925.0Mhz), UA_868 (868.0Mhz to 868.6Mhz), MY_919 (919.0Mhz to 924.0Mhz), SG_923 (917.0Mhz to 925.0Mhz), PH_915 (915.0Mhz to 918.0Mhz).
Although the SMA antenna socket is considered relatively rugged, if the antenna is subjected to a large external force while the Station G2 is moved, it is still possible to damage the SMA socket due to leverage. You may want to use a flexible antenna or antenna extension cable especially when the Station G2 is not used as a fixed or vehicle-mounted node. For handheld/wearable device application scenarios, you may also consider using the Nano series which have high performance wideband built-in antennas.
Meshtastic[2] Mesh Device Station G2 is an upgraded design of Station G1, using the latest ESP32 S3 MCU. As an RF research project, Station G2 also brings key updates in RF. The primary RF design goal of Station G2 is to improve the Lora receiving sensitivity by about 4dB based on a dedicated Ultra-Low Noise Figure LNA. And to increase the transmit power and improve Signal to Noise ratio of short data packets by designing the Fast-Transient DC-DC for 35dBm Lora PA.
For Lora Power Amplifier, the 1 dB Compression Point (P1dB) is 35 dBm (3.16 W), and the maximum RF output power is 36.5 dBm (4.46 W) for US915 and 37 dBm (5 W) for EU868.
Station G2 has a rugged SMA antenna socket and rich external IO interfaces. It can be powered by either 15VDC USB Type C PD protocol or 9VDC-19VDC External Power Supply. These features make Station G2 ideally suited as a Fixed-Location Base Station or Vehicle-Mounted Base Station.
¶ Features Comparison of Station G2 and Station G1
| Editions | Station G2 | Station G1 |
|---|---|---|
| Core Research Areas | Ultra-Low Noise Figure LNA for LoRa Fast-Transient DC-DC for LoRa PA |
Modern Cost-Effective RF Power Amplifier RF Components/Materials Measurement and Modeling |
| Photo |  |
 |
| Product Status | ACTIVE | DISCONTINUED |
| Current Hardware Version | 01 Jun 2024 | 20 Sep 2022 |
| Initial Release Date | 18 Jan 2024 | 12 Jun 2022 |
| Lora RF Max Output Power | Up to 35 dBm (P1dB Point) | Up to 35 dBm (Maximum RF Output Power) |
| Frequency Reference for Lora | 32MHz TCXO (+-1.5 ppm) | 32MHz XTAL (+-10 ppm) |
| Lora Ultra-Low Noise Figure LNA | Typical Gain: 18.5 dB, Typical Noise Figure: 1.8 dB | - |
| Fast-Transient DC-DC for LoRa PA | Transient Response Time < 18us, Maximum Transient Voltage Deviation < 275mV, Phase Margin > 66.73 Degrees, Ripple < 30mV, Test Condition: 0A-3A@7.5VDC Dynamic Test, Input Voltage 15VDC | - |
| LoRa Transceiver | SX1262 | SX1262 |
| Lora Operation Frequency | US915MHz / EU868MHz | US915MHz / EU868MHz |
| MCU | ESP32 S3 (Flash: 16MB, PSRAM: 8MB) | ESP32 (Flash: 4MB, PSRAM: -) |
| WIFI | YES | YES |
| Bluetooth | v5.0 | v4.2 |
| Satellite Navigation | Optional (1x GROVE GPS Socket) | Optional |
| USB Connector | Type C (PD Protocol) | Type C (PD Protocol) |
| Screen | 1.3 Inch OLED Screen | 1.3 Inch OLED Screen |
| Battery | - | Optional 12V Battery Docker |
| Power Input Socket | 15VDC USB Type C PD protocol, 1x5P Pitch=1.5mm Socket (9VDC-19VDC External Power Supply) | USB Type C, 1x2P Pitch=2.5mm Socket |
| LoRa Antenna | SMA Socket | SMA Socket |
| Accessories | 1x GROVE GPS Socket, 1x GROVE I2C Socket, 1x SparkFun QWIIC I2C Socket and 1x IO Extension Socket | 1x IO Extension Socket |
| Typical Scenarios | Fixed-Location Base Stations and Vehicle-Mounted Base Stations | Fixed-Location Base Stations and Vehicle-Mounted Base Stations |
¶ Characteristics
| Item | Description |
|---|---|
| Lora Operation Frequency | 815 Mhz to 940 Mhz |
| Lora Max RF Output Power | 36.5 dBm (4.46 W) for US915 and 37 dBm (5 W) for EU868 |
| 1 dB Compression Point (P1dB) | 35 dBm |
| Lora Ultra-Low Noise Figure LNA | Typical Gain: 18.5 dB, Typical Noise Figure: 1.8 dB |
| LoRa Transceiver | SX1262 |
| High-Precision Frequency Reference for Lora | 32MHz TCXO (+-1.5 ppm) |
| WIFI | YES |
| Bluetooth | v5.0 |
| Positioning And Navigation Module | Optional (1x GROVE GPS Socket) |
| Item | Measured Value | Note |
|---|---|---|
| Typical Power Consumption (Lora TX Mode) | 854.67 mA @ 14.16V | SX1262 TX Power Setting = 17 dBm @ US915 PA Output Power = 35.5 dBm (3.55 W) Screen ON |
| Typical Power Consumption (Lora RX Mode) | 46.12 mA @ 14.16V | Screen ON |
| Item | Description |
|---|---|
| Size | 11cm x 5.8cm x 2.2cm |
| Color | Black |
| Weight | ~87.5g (Without Antenna) |
¶ Hardware
¶ Switch/Button Definition
| Icon | Type | Name | Description |
|---|---|---|---|
| Button | Program Button | Single press changes the page of information displayed on the screen. Double press sends a broadcast message of the device position.[1] |
|
| Button | Firmware Download Button | Press and hold Firmware Download Button Then single press Restart Button Finally release the Firmware Download Button The device is now forced into Firmware Download mode |
|
| Button | Restart Button | Single press restart ESP32 S3 |
[1] This function works if and only if when the supported GPS module is installed on the GROVE GPS Socket, or connected to a mobile phone with built-in GPS via Bluetooth.
¶ PCB
- Restart Button ( )
- Firmware Download Button ( )
- Program Button ( )
- ESP32 S3 (Flash: 16MB, PSRAM: 8MB)
- 32MHz TCXO (+-1.5 ppm), Part No. DSB211SDN from DAISHINKU CORP. (KDS)
- Lora Power Amplifier
- Semtech SX1262 Lora Transceiver
- Lora Ultra-Low Noise Figure LNA
- RF Switch
- SMA Connector for Lora Antenna
- USB Type C Socket
- FPC Connector for OLED Screen
- Fast-Transient 3.3V DCDC
- Fast-Transient 7.5V DC-DC for LoRa Power Amplifier
- 1x5P Pitch=1.5mm Socket (9V-19V External Power Supply, Cable Model: ZH 1.5mm 5P)
- GROVE I2C Socket( 1x4P Pitch=2mm )
- SparkFun QWIIC I2C Socket ( 1x4P Pitch=1mm, Cable Model: JST SH 1.0mm 4P)
- GROVE GPS Socket ( 1x4P Pitch=2mm )
- IO Extension Socket ( 1x10P Pitch=1.5mm, Cable Model: ZH 1.5mm 10P )
- HV LED (Green)
- PA LED (Blue)
- LV LED (Red)
¶ Power Status
| LV LED (Red) | HV LED (Green) | PA LED (Blue) | Description |
|---|---|---|---|
| ON | OFF | OFF | 3.3V DCDC is working normally, but 7.5V DCDC is not working. Generally, this status indicates the device is powered up by using USB2.0/3.0 which does not support 15V USB Type C PD protocol. For this status, everything should work normally, except the Lora PA. The firmware can be flashed into the device through Type C Port in this status. |
| ON | ON | ON | Both 3.3V DCDC and 7.5V DCDC are working normally. Generally, this status indicates the device is powered up by either 15V USB Type C PD protocol or 9V-19V External Power Supply. For this status, everything should work normally. |
¶ Mechanical Design
Similar as Station G1, the Station G2 is also constructed by stacking up PCB boards.This method offers a good balance of cost and mechanical strength. The Station G2 employs an aluminum substrate PCB (sliver) as heat sink for high power lora PA. Nonelectrical conductivity high performance thermal grease is applied between the heat sink and the main PCB.
Note: Green Rectangle - Nylon Machine Screws and Nuts
| Item | Quantity |
|---|---|
| M3x15mm Screws | 4 |
| M3x10mm Screws | 2 |
| M3 Nuts | 4 |
| Hexagon Female-Female M3x6mm Studs | 6 |
Front Side and Bottom Side of the case.
¶ RF Design - Lora
¶ Lora Power Amplifier
According to the Conduction Test, the 1 dB Compression Point (P1dB) of Lora Power Amplifier is 35 dBm (3.16 W), and the maximum RF output power is 36.5 dBm (4.46 W) for US915 and 37 dBm (5 W) for EU868. Instrument Setup is exactly the same as Station G1.
Meshtastic firmware firmware_neil_station-g2-2.2.17.bin was flashed into the DUT. Meshtastic Android APP 2.2.20 had been used to control the DUT.
Note: SX1262 TX Power Setting = 18 dBm Region = “US” Modem preset = LONG_SLOW Channel Number = 27
¶ Summary for Lora Power Amplifier Conduction Test
Region = “US” Center Frequency = 905.3125 MHz Modem preset = LONG_SLOW Channel Number = 27
OR
Region = “EU868” Center Frequency = 869.4625 MHz Modem preset = LONG_SLOW Channel Number = 1
| SX1262 TX Power Setting | PA Output Power (US915) | PA Gain (US915) | PA Output Power (EU868) | PA Gain (EU868) | Description |
|---|---|---|---|---|---|
| 19 dBm | 36.5 dBm (4.46 W) | 17.5 dB | 37 dBm (5 W) | 18 dB | Maximum RF Output Power |
| 18 dBm | 36 dBm (3.98 W) | 18 dB | 36.5 dBm (4.46 W) | 18.5 dB | |
| 17 dBm | 35.5 dBm (3.55 W) | 18.5 dB | 36 dBm (3.98 W) | 19 dB | |
| 16 dBm | 35 dBm (3.16 W) | 19 dB | 35.5 dBm (3.55 W) | 19.5 dB | Recommended Setting for US915, 1 dB Compression Point (P1dB) for US915 |
| 15 dBm | 34.5 dBm (2.82 W) | 19.5 dB | 35 dBm (3.16 W) | 20 dB | Recommended Setting for EU868, 1 dB Compression Point (P1dB) for EU868 |
| 14 dBm | 34 dBm (2.51 W) | 20 dB | 34.5 dBm (2.82 W) | 20.5 dB | |
| 13 dBm | 33 dBm (2 W) | 20 dB | 34 dBm (2.51 W) | 21 dB | |
| 12 dBm | 32 dBm (1.58 W) | 20 dB | 33 dBm (2 W) | 21 dB | |
| 11 dBm | 31 dBm (1.26 W) | 20 dB | 32 dBm (1.58 W) | 21 dB | |
| 10 dBm | 30 dBm (1 W) | 20 dB | 31 dBm (1.26 W) | 21 dB | Default Setting, Operation with ISM band for US915 |
| 9 dBm | 29 dBm (0.79 W) | 20 dB | 30 dBm (1 W) | 21 dB | |
| 8 dBm | 28 dBm (0.63 W) | 20 dB | 29 dBm (0.79 W) | 21 dB | |
| 7 dBm | 27 dBm (0.5 W) | 20 dB | 28 dBm (0.63 W) | 21 dB | |
| 6 dBm | 26 dBm (0.4 W) | 20 dB | 27 dBm (0.5 W) | 21 dB | Operation with ISM band for EU868 |
Caution!
All measurements above are indicative and typical, and are not a specification. The RF output power accuracy of the Station G2 cannot be claimed to be better than the RF output power step accuracy of Semtech LoRa transceiver SX1262. Although the statistical accuracy of the Station G2's PA Output Power is +-1dBm based on the conduction test in quality inspection, we still cannot guarantee that the batch-to-batch tolerance of the SX1262 will not change in the future.
According to the datasheet of SX1262, table 3-9: Transmit Mode Specifications, on the page 21. The RF output power step accuracy of SX1262 is +-2 dB.
In summary, although the statistical accuracy of the Station G2's PA Output Power is +-1dBm, the PA Output Power accuracy should still be claimed to be +-2 dBm to be consistent with SX1262.
¶ Ultra-Low Noise Figure LNA for LoRa
The Station G2 features a dedicated Ultra-Low Noise Figure LNA, tailored specifically for the 800 MHz to 950 MHz frequency band. This LNA is not a generic commercial solution but is uniquely optimized for optimal performance within the 800 MHz to 950 MHz frequency range.
According to the right hand side S21 diagram, the typical gain of this LNA is 18.935dB @ 868Mhz and 18.775dB @915Mhz, and the typical Noise Figure of LNA is 1.8dB (Tested using Y-factor Method). Due to its relatively high gain and low noise figure, this LNA significantly enhances the receiving sensitivity of Station G2, which is approximately 4dB better than the Station G1. Additionally, the LNA also functions as a band-pass filter, improving the Signal-to-Noise Ratio (SNR) of the received signal.
¶ Quantitative Analysis of Receiving Sensitivity
The typical gain of LNA is 18.775dB @915Mhz, typical Noise Figure of LNA is 1.8dB, and the typical Noise Figure of SX1262 is 6dB[3]. Therefore, Station G2 Noise Figure and Receiving Sensitivity Improvement can be calculated by the following steps.
- Station G2 RX Noise Factor:
- Station G2 RX Noise Figure:
- Receiving Sensitivity Improvement:
The above calculation steps calculate the Receiving Sensitivity Improvement of the US915 MHz band = 4.088044118 dB. Using the same calculation steps, the Receiving Sensitivity Improvement of EU868 MHz is 4.092043763 dB.
¶ Conclusion for Ultra-Low Noise Figure LNA
Similar to Station G1, two Station G2 are required to achieve the maximum coverage, because the link budgets of the two communicating devices need to be equal to achieve the maximum coverage, otherwise the device with a lower link budget will become the system bottleneck.
Station G2 increases the link budget by about 4dB due to improved Receiving Sensitivity. Therefore, Station G2 has significantly larger coverage than Station G1.
When communicating with devices without PA, although the problem of link budget imbalance cannot be avoided and the link budget of devices without PA becomes the system bottleneck, the coverage will still be significantly improved because Station G2 improves Receiving Sensitivity. Therefore Station G2's LNA even could increase the link budget of devices without PA in the same mesh network.
¶ Reference Clock (TCXO) for LoRa
¶ Background Information
According to semtech's document AN1200.59 Selecting the Optimal Reference Clock[4]:
Devices that are mission critical and/or communicates as the master with other devices. For example, typical outdoor/indoor gateways use TCXO since any excessive frequency drift will affect multiple end-devices.
LoRa Radio Clock Absolute Accuracy Requirement in ppm (US915 Band, Single-Sided)
Bandwidth (kHz) 31.25 62.5 125 250 500 SF5 to SF10 8.5 17.1 34.2 68.3 136.6 SF11 8.5 17.1 34.2 68.3 100.0 SF12 8.5 17.1 34.2 50.0 50.0 The ppm offset in the Table indicates the required reference clock accuracy of the combined offset between the transmitter and receiver. This means that if the reference clock of the gateway is very accurate, the accuracy requirements for other nodes in the same network can be appropriately reduced.
For Meshtastic, if we want to achieve maximum coverage, we need to set Channel setting = Very Long Range / Slow, Bandwidth = 62.5kHz[5]. This means that LoRa Radio Clock Absolute Accuracy Requirement in ppm must be less than or equal to 17.1 ppm.
¶ TCXO Accuracy Verification
Because the typical application scenarios of Station G2 are Fixed-Location Base Stations and Vehicle-Mounted Base Stations, we chose 32MHz TCXO (+-1.5 ppm), Part No. DSB211SDN from DAISHINKU CORP. (KDS) for Station G2. This TCXO is also be chose for Nano G2 Ultra and Nano G1 Explorer.
Manufacturer's Accuracy Specifications:
We need to measure and verify the accuracy of TCXO, because the output frequency of TCXO may be affected by its peripheral circuit design and PCB parasitic parameters, so the frequency accuracy needs to be verified to ensure that the design meets the requirements.
According to the measurements of the picture on the right:
When the ambient temperature was 20 degrees Celsius, the Universal Counter used an external GPS Disciplined Oscillator (Output frequency: 10.000000.000MHz +-0.001Hz) as the reference clock, the supply voltage of the TCXO was set to 1.8V. In addition, in order to simulate 2 times reflow, we used 370 degrees Celsius hot air to solder the same TCXO 2 times.
So, the accuracy of the TCXO in ppm:
According to the above calculation, Station G2's LoRa Radio Clock Accuracy <= +- 1.16 ppm, which is better than the Manufacturer's Accuracy Specification (+- 1.5 ppm).
We also used the statistical function of Universal Counter to obtain 100 measurement results, and ActualFrequency is exactly the same. This shows that the TCXO has excellent output frequency stability.
¶ Conclusion for Reference Clock (TCXO) for LoRa
The application scenario of Station G2 determines that it is often used as the core router in the mesh network. Its LoRa Radio Clock Accuracy will affect all other nodes that use it to forward messages, so its TCXO design is crucial. According to the measurements and calculations, we know that the Station G2's LoRa Radio Clock Accuracy <= +- 1.16 ppm when the supply voltage of the TCXO was set to 1.8V. So that, it can be proved the TCXO related design of Station G2 meets the design requirements.
¶ Fast-Transient DC-DC for LoRa Power Amplifier
Station G2's Lora PA consumes almost no power in RX mode, and consumes about 1.2A@7.5VDC in TX mode. When the load's current draw jumps from 0A@7.5VDC to 1.2A@7.5VDC, the Lora PA's power supply voltage will drop for a period of time, until the DCDC's feedback control system corrects the voltage to the target value. While this voltage drop is inevitable, we still can optimize the DCDC to minimize the transient response time and consequently reduce the transient voltage deviation.
Transient voltage deviation is very important for Lora PA because RF output power and Lora PA's supply voltage are positively correlated. Optimizing and minimizing the transient response time and consequently reducing the transient voltage deviation can effectively shorten the time of the RF output power dropping. Smaller transient voltage deviation can also ensure that even when Lora PA's supply voltage drops slightly, the RF output power can still be guaranteed to not drop significantly. The above reasons are why we specially developed and optimized the Fast-Transient DC-DC solution for Station G2.
¶ Quantitative Analysis of Lora PA's Fast-Transient DC-DC
Test Condition: 0A-3A @ 7.5VDC Dynamic Test, Input Voltage 15VDC
Since the current jump range of Lora PA is 0A to 1.2A @7.5V, our test conditions are far more aggressive than the Lora PA's working condition. Therefore, the Transient Response Time and Maximum Transient Voltage Deviation when the PA is working should be significantly better than the test results. In other words, the test results in this section represent worst-case data.
¶ Transient Response Time, Maximum Transient Voltage Deviation and Ripple
According to the test results in the above figure, for 0A-3A @ 7.5VDC Dynamic Test, Input Voltage = 15VDC:
- Transient Response Time = 18us
- Maximum Transient Voltage Deviation = 273.4mV
- Ripple = 26.6 mV for Load Current 3A @ 7.5V
From the moment the programmable electronic load initiates a draw of 3A@7.5V, causing a dip in the DCDC output voltage, to the point when the DCDC's feedback control system corrects the output voltage to the preset value, the whole process takes a total of 128us.
For the Lora PA powered by 7.5VDC, the influence of Maximum Transient Voltage Deviation = 273.4mV on the RF output power is negligible.
At the same time, we can see the process of the DCDC's feedback control system correcting the output voltage. The voltage curve is very smooth and there is no oscillation. The smoothness of the control process is determined by Phase Margin. This parameter is very important for the SNR of the RF transmission signal, especially for short data packets.
¶ Phase Margin and Gain Crossover Frequency
The phase margin is the amount of allowable variation in the phase of the plant before the closed-loop becomes unstable. In real world designs we usually require Phase Margin to be at least greater than 45 degrees.
| Load Current | Gain Crossover Frequency | Phase Margin |
|---|---|---|
| 0A | 744.1 kHz | 161.9° |
| 0.5A | 235.4 kHz | 140.5° |
| 1A | 127.2 kHz | 70.33° |
| 2A | 127.3 kHz | 76.63° |
| 3A | 101.8 kHz | 66.73° |
| 4A | 258.4 kHz | 150.2° |
According to the above test data, Lora PA's Fast-Transient DC-DC is stable between Load Current from 0A to 4A @7.5V. This ensures that the SNR does not get worse when transmitting short data packets.
¶ Conclusion for Lora PA's Fast-Transient DC-DC
Through the optimization of Lora PA's Fast-Transient DC-DC, the RF transmission power and SNR of short data packets are improved. This means that ACK[6], Traceroute[7] and Range Test Module[8] related data packets will get further coverage. Station G2 will have a lower re-transmission probability than Station G1, thereby saving power. In addition, Traceroute and Range Test Module will also have a higher probability of being successfully executed from a greater distance.
¶ Power Consumption Measurement
¶ Instrument Setup
To test the power consumption when powered by External Power Supply, connect the Micro Power Analyzer to the Station G2's (Hardware Version: 18 Jan 2024) USB Type C Connector. The power supply voltage is set to 14.16V.
The following items will be measured:
- Lora TX mode, Screen ON
- Lora RX mode, Screen ON
¶ Measurements
- Lora TX mode, SX1262 TX Power Setting 17 dBm @ US915, PA Output Power 35.5 dBm (3.55 W), Screen ON = 854.67 mA @ 14.16V
- Lora RX mode, Screen ON = 46.12 mA @ 14.16V
For Lora TX mode, power consumption has a great relationship with the VSWR of the antenna. The closer the VSWR is to 1, the higher the power consumption. PA Output Power has little relationship with power consumption. Even if we set PA Output Power to 36.5 dBm (4.46 W), the power consumption will not increase significantly.
For Lora RX mode, the PA consumes almost no power for RX mode, and most of the power consumption is consumed by ESP32 S3 MCU. Therefore, although ESP32 S3 has higher performance than the previous generation ESP32, it also brings higher power consumption. The power consumption of ESP32 S3 is also significantly higher than the NRF52840 MCU used by Nano G2 Ultra. ESP32 is one of the MCUs currently supported by the Meshtastic firmware that has WIFI, which is the main reason why we still choose ESP32 S3.
¶ Summary for Power Consumption Measurement
| Item | Measured Value | Note |
|---|---|---|
| Lora TX mode | 854.67 mA @ 14.16V | SX1262 TX Power Setting = 17 dBm @ US915 PA Output Power = 35.5 dBm (3.55 W) Screen ON |
| Lora RX mode | 46.12 mA @ 14.16V | Screen ON |
¶ The Latest Firmware
You may need to manually set Station G2 to enter the Firmware Download mode.
1.Connect the device to the computer using a USB cable.
2.Press and hold Firmware Download Button
3.Then single press Restart Button
4.Wait for 5 seconds ( For Windows, you may hear a sound when the USB device is reconnected automatically )
5.Finally release the Firmware Download Button
The device is now forced into Firmware Download mode
Note: After the flashing process is complete, you may need to single press Restart Button if the device does not reboot automatically.
Meshtastic Mesh Device Station G2 had been supported by the official meshtastic repository on Github from firmware version 2.2.24. Thus, the latest firmware could be downloaded from the meshtastic project’s releases page: https://github.com/meshtastic/Meshtastic-device/releases
Firmware file: firmware-station-g2-2.x.x.bin
Following instructions to flash it to the Station G2: https://meshtastic.org/docs/getting-started/flashing-firmware/esp32/
¶ Pull Requests related to Station G2
| Pull Request | Date | Github URL | Description |
|---|---|---|---|
| #3282 | 25-Feb-2024 | Station G2 #3282 | Initial Support for Station G2 |
¶ Software
¶ Android
The Android APP could be downloaded and installed from the Google Play Store: https://play.google.com/store/apps/details?id=com.geeksville.mesh
APP Source Code: https://github.com/meshtastic/Meshtastic-Android/releases
¶ iOS
The iOS APP could be downloaded and installed from following URL: https://meshtastic.org/docs/category/apple-apps
¶ Python / MQTT and More
Python, Web Interface and MQTT are also supported by the Meshtastic. More information: https://meshtastic.org/docs/software
¶ Advanced Topics
¶ TX Power Setting
Prerequisites
Execute following command by using Meshtastic CLI, this operation will set the SX1262 TX Power to 17 dBm:
meshtastic --set lora.tx_power 17
Output:
Connected to radio
Set lora.tx_power to 17
Writing modified preferences to device
Verification, execute following command:
meshtastic --get lora.tx_power
Output:
Connected to radio
lora.tx_power: 17
Completed getting preferences
According to the Summary for Lora Power Amplifier Conduction Test, the PA Output Power is expected to be 35.5 dBm (3.55 W) for US915, after executing above command.
¶ Accessories
GPIO access is fundamentally dangerous because invalid options can physically damage or destroy your hardware. Ensure that you fully understand the schematic for your particular device before trying this.
Station G2 has 1x GROVE I2C Socket( 1x4P Pitch=2mm ), 1x SparkFun QWIIC I2C Socket ( 1x4P Pitch=1mm ), 1x GROVE GPS Socket ( 1x4P Pitch=2mm ) and 1x IO Extension Socket ( 1x10P Pitch=1.5mm ). These connectors can be used to support accessory devices and designs.
Note: IO definition, all VCC = 3.3VDC
¶ GROVE I2C Socket and SparkFun QWIIC I2C Socket
Station G2 has two I2C sockets, which are used to connect GROVE[9], Adafruit STEMMA QT[10] and SparkFun QWIIC[11] devices.
¶ Meshtastic supported I2C devices
¶ Telemetry Module
Supported sensors connected to the I2C bus of the device will be automatically detected at startup. Environment Telemetry and Air Quality must be enabled for them to be instrumented and their readings sent over the mesh.
| Sensor | I2C Address | Data Points |
|---|---|---|
| BMP280 | 0x76, 0x77 | Temperature and barometric pressure |
| BME280 | 0x76, 0x77 | Temperature, barometric pressure and humidity |
| BME680 | 0x76, 0x77 | Temperature, barometric pressure, humidity and air resistance |
| MCP9808 | 0x18 | Temperature |
| INA260 | 0x40, 0x41 | Current and Voltage |
| INA219 | 0x40, 0x41 | Current and Voltage |
| LPS22 | 0x5D, 0x5c | Barometric pressure |
| SHTC3 | 0x70 | Temperature and humidity |
| SHT31 | 0x44 | Temperature and humidity |
| PMSA003I | 0x12 | Concentration units by size and particle counts by size |
More Information: https://meshtastic.org/docs/settings/moduleconfig/telemetry
Note: Station G2 with GROVE I2C compatible BMP280 Sensor, sensor data will also be displayed on the mobile APP (Picture on the right hand side)
¶ Canned Message Module
Canned Message Module and M5Stack CardKB[12] can turn Station G2 into a stand-alone device, which can send and receive messages without a mobile phone.
- M5Stack CardKB
The CardKB is fully supported in freetext mode and select mode. Use UP/DOWN/ENTER to select a predefined message and send it. For a freetext message, just type it in and press ENTER to send it.
If you don't want to broadcast your freetext message, you can use the CardKB to send it to a specific node. Just press TAB and select the target node with the LEFT/RIGHT keys. The message will be sent to the node with the matching name and node number. The target node will be remembered for your next message.
More Information: https://meshtastic.org/docs/settings/moduleconfig/canned-message#cardkb
Note: Station G2 with M5Stack CardKB (a GROVE I2C compatible keyboard)
¶ GROVE GPS Socket
Meshtastic firmware supports almost all GPS modules using NMEA format and TTL serial port. This means that most GPS modules on the market can be connected to Station G2 by simply connecting their VCC, GND, GPS_RXD and GPS_TXD to a cable compatible with GROVE UART ( 1x4P Pitch=2mm ) . The most convenient way is to directly use GROVE's official GPS module[13] or a module compatible with it.
After the firmware is updated, the GPS function may be disabled, and you may need to re-enable the GPS function so that the GPS module is automatically discovered and initialized when the device starts.
More Infomation: https://meshtastic.org/docs/configuration/radio/position/
Note: Station G2 with GROVE's official GPS module (a GROVE UART GPS)
¶ IO Extension Socket
IO Extension Socket (1x10P Pitch=1.5mm) includes VCC (3.3VDC), GND and 8 user-configurable ESP32 GPIOs. These GPIOs can be controlled using Meshtastic's Remote Hardware Module[14], or you can modify and compile the Meshtastic firmware yourself to implement more complex functions.
More Information: https://meshtastic.org/docs/configuration/module/remote-hardware/
¶ External Power Supply
Station G2 can be powered by either 15VDC USB Type C PD protocol or 9VDC-19VDC External Power Supply (The maximum output power should be greater than or equal to 20W). When using 9VDC-19VDC External Power Supply, a 1x5P Pitch=1.5mm cable (Model: ZH 1.5mm 5P Cable) is required to connect Station G2 to the power supply. This connector also comes with the reverse polarity protection.
Note: Power cable definitions are marked on the back of the case.
| Mark Symbol | Description |
|---|---|
| + | The two pins marked "+" need to be connected to the positive terminal of the 9VDC-19VDC power supply. |
| S | This pin is a reserved pin, keep floating. |
| - | The two pins marked "-" need to be connected to the negative terminal of the 9VDC-19VDC power supply. |
¶ FCC Rules and Regulations
¶ Operation with ISM band
Any RF device can transmit encrypted data in the ISM bands without license. However, the maximum transmitter power fed into the antenna should be less than or equal to 30dBm (1W).
| ISM Bands |
|---|
| 902 to 928 MHz |
| 2.400 to 2.4835 GHz |
| 5.725 to 5.875 GHz |
Benefit from high power PA even when operating in the ISM bands. For example, if there is a long coaxial cable between the transmitter and the antenna, the coaxial cable may have considerable insertion loss. At this time, the transmitting power of the transmitter can be increased to ensure exactly 30dBm power feeding into the antenna.
Reference
- FCC Rules for Unlicensed Wireless Equipment operating in the ISM bands. Retrieved Jun 1, 2022, from https://afar.net/tutorials/fcc-rules/
¶ Operation with Amateur Radio License
Lora 915MHz is exactly 33cm band in the amateur bands. With Amateur Radio License, according to the National Association for Amateur Radio's description, the transmitter can transmit unencrypted data using up to 1500W. However, since Lora is considered a spread spectrum, according to Part 97.311, the transmitter can transmit unencrypted data using up to 10W.
This official document describes in detail how to turn off Meshtastic's encryption: Licensed (HAM) Operation.
How to increase the Lora RF output power: TX Power Setting
Copyright: The National Association for Amateur Radio
Reference
- US Amateur Radio Frequency Allocations. Retrieved Jun 1, 2022, from http://www.arrl.org/frequency-allocations
- US Amateur Radio Technician Privileges. Retrieved Jun 1, 2022, from http://www.arrl.org/files/file/Tech Band Chart/US Amateur Radio Technician Privileges.pdf
- Amateur Radio Allocations and Overlapping Part 15 Bands - An Overview and a Part 97 versus Part 15 and Permissible Power Comparison. Retrieved Jun 28, 2022, from https://www.qsl.net/kb9mwr/projects/wireless/allocations.html
- FCC Proposes to Eliminate Spread Spectrum APC Requirement, Reduce Spread Spectrum Power Limit; Cleans Up Portions of Part 97. Retrieved Aug 03, 2024, from http://www.arrl.org/news/fcc-proposes-to-eliminate-spread-spectrum-apc-requirement-reduce-spread-spectrum-power-limit-cleans
- 97.313 Transmitter power standards. Retrieved Aug 03, 2024, from https://www.ecfr.gov/current/title-47/section-97.313
¶ Use Cases
Due to the excellent Lora transmission/reception performance of Station G2, Station G2 is used to build backbone mesh networks in many regional Meshtastic communities.
Since the receiving sensitivity of Station G2 is about 4dB higher than that of most other devices. In addition, the LNA can also be used as a bandpass filter to improve the signal-to-noise ratio (SNR) of the received signal. This allows Station G2 to receive weaker signals, thereby helping more low-power nodes in the area to relay messages. The deployment of Station G2 helps build a larger coverage and more stable Meshtastic Mesh network.
¶ Meshtastic Bay Area Group
The following figure shows a typical coverage map of Station G2 OHR node (PA Output Power = 30 dBm @ US915) deployed by Meshtastic Bay Area Group in California. (Screenshot taken on 18-Jul-2024):
¶ Community Projects
The following projects are created and shared by Station G2 users. The copyright belongs to the corresponding creators, please check the license of the corresponding project. Thanks to the creators for their efforts and sharing.
Note: We cannot provide technical support for community projects.
¶ 3D Printing Projects
| Project Name | Description | Authors |
|---|---|---|
| Station G2 Shell Discussions | Discussions about the Station G2 Shell on the Meshtastic official discord. You may need a discord account to access this content. | Station G2 Users |
| Station G2 Case and Battery Holder | Lucas designed this case for the Station G2 to add some protection, as well as an attachable battery case for the popular VEEKTOMX Mini Power Bank 10000mAh. | Lucas Gahler |
| Station G2 Veektomx Battery Mount Holder | Sumnips designed this case for the Station G2 to be stacked on top of, or replace the backplate of a Station G2 to hold the VEEKTOMX Mini Power Bank 10000mAh. | Sumnips |
¶ Software Projects
| Project Name | Description | Authors |
|---|---|---|
| Minimal LoRa G2 | A Minimal LoRa Micropython implementation for the G2 Station. | Kongduino |
¶ Datasheet
| Part No. | Datasheet | Description |
|---|---|---|
| DSB211SDN | dsa_dsbxxxsdn_en.pdf | 32.000MHz TCXO (+-1.5 ppm) |
| SX1262 | sx1262_datasheet.pdf | Semtech SX1262 Lora Transceiver |
¶ FAQ
¶ About the USB Type C Power Adapter
Station G2 can be powered by a USB Type C power adapter that supports PD 15V protocol and has a maximum output power of 20W or more. However, a Type C to Type C cable must be used to trigger the PD protocol. There are 3 LEDs on the Station G2 that can be used to check if the power supply is normal. Click here for more information.
Please use reputable products, because substandard adapters usually have very high ripple, which may affect the receiving sensitivity. A typical situation is that the transmission performance is normal, but the receiving performance is very poor. Excessive power ripple may exceed the capability of the DCDC to reject (suppress) input voltage ripple. Because the waveform of the received signal is very weak, noise may eventually make the received signal undecodable. If this happens, try using a different power adapter to troubleshoot the issue.
¶ Can I use a power bank to power Station G2?
The G2 station needs to be powered by a power bank that supports at least 9VDC USB Type C PD protocol, and preferably supports 15VDC USB Type C PD protocol. Even if your power bank supports the above protocols, it is still not guaranteed to be compatible with Station G2. This is because the power consumption of Station G2 is relatively low when it is in the receiving state, which may trigger the protection mechanism of some power banks and automatically shut down themself. You may search for the keyword "power bank auto off" for more information. According to our test results, two of the three different power banks are compatible with the Station G2, so incompatibility does occur.
¶ Community-Verified Compatible Power Banks for Station G2
Following Power Banks have been verified by the user community for compatibility with the Station G2. These Power Banks are sold by third-party sellers. We have not tested the quality of the Power Banks, so we cannot make any guarantee for the quality of the Power Banks. In addition, manufacturers may update the design in the future without changing the product model, which may also lead to incompatibility.
| Product Photo | Product Name | Model | Type-C Output | Product URL |
|---|---|---|---|---|
 |
VEEKTOMX Mini Power Bank 10000mAh Note: the size of this power bank is basically same as Station G2. |
VT103 | 5V/3.0A 9V/2.2A 12V/1.5A | Amazon Price: 25.99 USD for Black Edition on 21-Mar-2024 |
 |
Jackery Explorer 100 Plus Portable Power Station, 31,000mAh Portable Charger 99Wh LiFePO4 Battery Pack with 128W Output, PD 3.0 Fast Charge Note: please make sure Energy Saving Mode is disabled according to the manual. |
JE-100A | PD 100W Max | Amazon Price: 129 USD on 11-Apr-2024 |
¶ Antenna considerations
We recommend starting with the stock antenna, even if you plan to upgrade later. Use the stock antenna for a few days to establish a baseline RF performance for comparison with other antennas. Most Station G2 routers in key locations on the mesh map use the stock antenna.
The stock antenna, the TX915-JKS-20 for US915 or TX868-JKD-20 for EU868, has a gain of 3 dBi, providing fewer dead spots. It is also a sleeve dipole design, which means its resonant frequency and radiation pattern are less affected by the device's ground plane.
Keep in mind that a high-gain antenna does not necessarily offer better coverage. High-gain antennas are often monopole designs, which are more sensitive to the device's ground plane[15][16]. This sensitivity can affect both the resonant frequency and the radiation pattern, making high-gain antennas prone to coverage issues. Additionally, high-gain monopole omnidirectional antennas have reduced vertical coverage, meaning they radiate less energy above and below the antenna. As a result, achieving consistent RF performance with high-gain antennas can be challenging, with significant performance variations between devices due to differences in ground planes.
For these reasons, starting with a dipole antenna with approximately 3 dBi gain is the safest and most reliable option.
¶ Community-Verified Compatible Antennas
Following Antennas have been verified by the user community for compatibility with the Station G2. These Antennas are sold by third-party sellers. We have not tested the quality of the Antennas, so we cannot make any guarantee for the quality of the Antennas.
| Product Name | Antenna Type | Connectors | Center Frequency | Impedance Bandwidth | Peak Gain | Product URL | Datasheet |
|---|---|---|---|---|---|---|---|
| TE Connectivity Linx ANT-916-CW-HW | Center-fed Dipole | SMA | 916MHz | 900-930MHz | 1.2dBi | digikey.com Price: 9.41 USD on 29-Sep-2024 |
ANT-916-CW-HW |
| ALFA AOA-915-5ACM | Center-fed Dipole | N-male Connector Note: N to SMA adapter is required |
915 MHz | 902-928 MHz | 5dBi ( Over Stated Gain? ) | rokland.com Price: 16.97 USD on 29-Sep-2024 |
AOA-915-5ACM |
| ALFA AOA-868-5ACM | Center-fed Dipole | N-male Connector Note: N to SMA adapter is required |
868 MHz | 863-870 MHz | 5dBi ( Over Stated Gain? ) | rokland.com Price: 12.97 USD on 29-Sep-2024 |
AOA-868-5ACM |
¶ Impact of Lora node-dense areas/high-noise environments on RF performance
With the popularity of Lora and Meshtastic, a few urban areas have become Lora node-dense areas. These areas have high in-band/out-band noise, which may exceed the noise suppression capability of Station G2's LNA built-in bandpass filter. Therefore, a very rare phenomenon may occur where the RSSI data is higher (better) than the devices without LNA, but the SNR is lower (worser). This means that the signal received by Station G2 contains a high proportion of noise. Since the receiving sensitivity of Station G2 is about 4dB higher than other devices without LNA, the theoretical receiving coverage is about 1.58 times greater than other devices, which also means that Station G2 may receive noise from more noise sources.
If Station G2 is installed in the Lora node-dense area and the SNR is found to be significantly lower than a device without LNA, the following methods can be used to further suppress the received noise, from low to high effectiveness.
- Turn off boosted RX gain, more info: https://meshtastic.org/docs/configuration/radio/lora/#sx126x-rx-boosted-gain
- Connect the Station G2 directly to the antenna. Do not use coax cable or use a proper Line Isolator.
The reason is noise can be coupled through the outer metal braid of the coax cable to the device's GND. Watersstanton has two excellent youtube videos explaining this problem:
Line Isolator - Installing and Testing
Coax Line Isolator Basics - Reduce Noise and Hot Spots - Using a proper Cavity Filter (This is the simplest and most effective method)
According to user feedbacks, this method has never failed so far, even in the noisiest areas. Cavity filters are excellent bandpass filters that usually have very narrow passbands and perform much better than Station G2's LNA built-in bandpass filter. By suppressing the noise with cavity filter, the SNR can be greatly improved while still having about 4dB improvement in receiving sensitivity.
¶ Community-Verified Compatible Cavity Filters
Following Cavity Filters have been verified by the user community for compatibility with the Station G2. These Cavity Filters are sold by third-party sellers. We have not tested the quality of the Cavity Filters, so we cannot make any guarantee for the quality of the Cavity Filters. In addition, manufacturers may update the design in the future without changing the product model, which may also lead to incompatibility.
| Product Photo | Product Name | Connectors | Center Frequency | Product URL |
|---|---|---|---|---|
 |
915MHz Cavity Filter | SMA-female /SMA- female | 915MHz | aliexpress.us acasom.com Price: 65 USD on 29-Sep-2024 |
 |
868MHz Cavity Filter | SMA-female /SMA- female | 868MHz | aliexpress.us acasom.com Price: 65 USD on 29-Sep-2024 |
 |
Meshtastic LoRa 906.875MHz Cavity Filter | SMA-female /SMA- female | 906.875MHz | shop.airframes.io Price: 100 USD on 29-Sep-2024 |
¶ Reference
RegionInfo. Retrieved Feb 20, 2023, from https://github.com/meshtastic/firmware/blob/master/src/mesh/RadioInterface.cpp ↩︎
Meshtastic Project. Retrieved Feb 13, 2023, from https://meshtastic.org ↩︎
AN1200.22: LoRa Modulation Basics. Retrieved Feb 04, 2024, from https://lora-developers.semtech.com/documentation/product-documents/ ↩︎
AN1200.59 Selecting the Optimal Reference Clock. Retrieved Mar 10, 2024, from https://lora-developers.semtech.com/documentation/product-documents/ ↩︎
Radio Settings. Retrieved Mar 10, 2024, from https://meshtastic.org/docs/overview/radio-settings/ ↩︎
Mesh Broadcast Algorithm. Retrieved Feb 07, 2024, from https://meshtastic.org/docs/overview/mesh-algo/ ↩︎
Traceroute Module Usage. Retrieved Feb 07, 2024, from https://meshtastic.org/docs/configuration/module/traceroute/ ↩︎
Range Test Module Configuration. Retrieved Feb 07, 2024, from https://meshtastic.org/docs/configuration/module/range-test ↩︎
Grove I2C. Retrieved Feb 07, 2024, from https://wiki.seeedstudio.com/Grove_System/#grove-i2c ↩︎
Adafruit STEMMA QT. Retrieved Feb 07, 2024, from https://learn.adafruit.com/introducing-adafruit-stemma-qt/what-is-stemma-qt ↩︎
Qwiic Connect System. Retrieved Feb 07, 2024, from https://www.sparkfun.com/qwiic ↩︎
CardKB Mini Keyboard Programmable Unit V1.1 (MEGA8A). Retrieved Feb 07, 2024, from https://shop.m5stack.com/products/cardkb-mini-keyboard-programmable-unit-v1-1-mega8a ↩︎
Grove - GPS (Air530),GPS location, Long-distance communication. Retrieved Feb 07, 2024, from https://www.seeedstudio.com/Grove-GPS-Air530-p-4584.html ↩︎
Remote Hardware Module Usage. Retrieved Feb 07, 2024, from https://meshtastic.org/docs/configuration/module/remote-hardware/ ↩︎
Monopole vs Dipole Antenna. Retrieved Oct 01, 2024, from https://resources.pcb.cadence.com/blog/monopole-vs-dipole-antenna ↩︎
TI.16.5F11 915MHz 5dBi Outdoors Omni-Directional Rigid Whip Antenna. Retrieved Oct 12, 2024, from ti_16_5f11-3400259.pdf ↩︎