FPV Ground Station

Real-time FPV ground station with live telemetry dashboard

A budget-friendly, real-time FPV ground station built in Go with an embedded React web UI. Receives LTM (Lightweight Telemetry) data over a serial connection and displays live flight data in the browser. Ships as a single binary — no external dependencies at runtime. Pair it with a couple of LoRa modules and a USB-TTL adapter for a complete long-range telemetry setup without expensive dedicated hardware.

Features

• Flight instruments — attitude indicator (artificial horizon), heading compass, speed, and altitude
• Interactive map — live position tracking and flight path on OpenStreetMap (Leaflet)
• Telemetry panels — battery voltage, GPS status, navigation, home position, and sensor data
• Connection stats — frame rate (FPS), total frame count, CRC errors, uptime
• Real-time updates — WebSocket broadcast at 20 Hz (50 ms interval)
• Single binary — web UI is embedded at compile time, just run and open the browser

Example Hardware Setup

                         Drone                                  Ground Station

┌────────────────────┐    UART   ┌──────────┐        ┌──────────┐   UART    ┌────────┐  
│ Flight Controller  ├──────────→│ E22 LoRa │)))  (((│ E22 LoRa ├──────────→│   PC   │
│ (INAV / Betaflight)│    LTM    └──────────┘   AIR  └──────────┘  USB/TTL  └────────┘
└────────────────────┘                                                  fpv-ground-station

The flight controller outputs LTM on a spare UART. A pair of LoRa modules (e.g. EBYTE E22-900T) provides a long-range radio link. On the ground side, the LoRa module connects to the PC via a USB-to-TTL adapter. Ground Control reads from that serial port and serves the dashboard.

Preferred E22 parameters: 19200 baud rate with 19.2 kbps air data rate. This gives an optimal balance between range and latency for LTM telemetry.

This is just one example — any serial connection carrying LTM data will work (direct USB, Bluetooth serial, SiK radio, etc.).

Quick Start

Download the latest binary from Releases, then:

macOS / Linux:

./fpv-ground-station -port /dev/ttyUSB0 -baud 19200

Windows (PowerShell):

.\fpv-ground-station-windows-amd64.exe -port COM3 -baud 19200

Open http://localhost:8080 in your browser.

Usage

fpv-ground-station [flags]

Flag	Short	Default	Description
--port	-p	/dev/cu.usbserial-840	Serial port path
--baud	-b	19200	Baud rate
--web		:8080	Web UI listen address
--json		false	Output JSON lines to stdout
--dev		false	Dev mode (proxy to Vite dev server)

The PORT and BAUD environment variables can be used to override the default serial port and baud rate.

Platform-Specific Serial Ports

Platform	Example
macOS	/dev/cu.usbserial-*
Linux	/dev/ttyUSB0, /dev/ttyACM0
Windows	COM3

Building from Source

Prerequisites

• Go 1.25+
• Bun (or Node.js) for building the web UI

git clone https://github.com/ibrahimsn98/ground-control.git
cd ground-control
make build

The binary is output to bin/fpv-ground-station.

Supported Platforms

• macOS — primary development platform
• Linux — tested
• Windows — supported via Go cross-compilation

Any platform with Go 1.25+ and serial port support should work.

Supported Protocols & Flight Controllers

LTM (Lightweight Telemetry)

LTM is the only protocol currently supported. It is a lightweight, transmit-only telemetry protocol designed for low-bandwidth links.

Flight Controller	LTM Support	Notes
INAV	Full	All 6 frame types (G, A, S, O, N, X). N and X frames are INAV extensions.
Betaflight	Partial	Supports core LTM frames. N/X frames are INAV-specific and may not be available.
ArduPilot	No	ArduPilot uses MAVLink natively. LTM is not available.

LTM Protocol

LTM uses a simple frame structure:

$  T  <function>  <payload...>  <checksum>
│  │      │            │             │
│  │      │            │             └─ XOR of payload bytes
│  │      │            └─ Variable length, little-endian
│  │      └─ Single byte: G, A, S, O, N, or X
│  └─ Header byte 2 (0x54)
└─ Header byte 1 (0x24)

Frame Types

Frame	Name	Payload	Frequency	Key Data
G	GPS	14 bytes	~5 Hz	Latitude, longitude, ground speed, altitude, satellites, fix type
A	Attitude	6 bytes	~10 Hz	Pitch, roll, heading
S	Status	7 bytes	~5 Hz	Battery voltage, mAh drawn, RSSI, airspeed, armed/failsafe, flight mode
O	Origin	14 bytes	~1 Hz	Home latitude, longitude, altitude, fix
N	Navigation	6 bytes	~4 Hz	GPS mode, nav mode, nav action, waypoint number, nav error
X	Extended	6 bytes	~1 Hz	HDOP, hardware status, packet counter, disarm reason

Note: N (Navigation) and X (Extended) frames are INAV extensions and may not be present on other flight controller firmware.

Baud Rate & LTM Update Rate

INAV supports three LTM update rates, allowing you to trade telemetry frequency for lower bandwidth (and potentially longer radio range):

Setting	Data Rate	Min Baud	Use Case
NORMAL	~303 B/s	4800 bps	Default — all frames at full rate
MEDIUM	~164 B/s	2400 bps	Reduced bandwidth
SLOW	~105 B/s	1200 bps	Maximum range (LoRa, low-speed links)

Lower baud rates allow lower air-speed on radio links, which can increase range. LTM is transmit-only (no bidirectional communication required), so it works well on soft serial ports and simplex radio links.

Flight Controller Configuration (INAV)

1. Enable LTM on a spare UART in INAV Configurator:
   • Go to the Ports tab
   • Find an available UART (e.g. UART3)
   • Enable LTM under the "Telemetry Output" column
   • Set the baud rate (19200 is a good default)

2Adjust update rate (optional):

set ltm_update_rate = NORMAL
save

Use MEDIUM or SLOW for low-bandwidth links like LoRa.

Project Structure

ground-control/
├── cmd/fpv-ground-station/  # Application entry point, embed logic
├── internal/
│   ├── ltm/                # LTM protocol parser and frame decoder
│   ├── serial/             # Serial port wrapper
│   ├── server/             # HTTP + WebSocket server
│   └── telemetry/          # Telemetry state store and stats
├── web-ui/                 # React + Vite + Tailwind dashboard
│   └── src/
│       ├── components/     # Dashboard, flight instruments, map, panels
│       ├── hooks/          # WebSocket telemetry hooks
│       ├── providers/      # Telemetry context provider
│       └── types/          # TypeScript type definitions
└── Makefile

Running Tests

make test

References

• INAV LTM Wiki — protocol specification and configuration details

License

Apache License 2.0