# J.Fi

URL: https://jmarple.ai/products/j-fi/
Category: Wireless Link

Wireless link for drones and robots

J.Fi is a compact module for drones, robots, and IoT devices. It runs on the 2.4GHz WiFi band and supports N:N networks, in which every device can send data to every other device.

[Simultaneous control using J.Fi - 3 devices](https://www.youtube.com/watch?v=tPeJA2gn7Zw)

## Why J.Fi?

### Range and speed

J.Fi reaches up to 1 km, depending on the environment. The data rate can be set from 250Kbps to 11Mbps, and each payload can be up to 1024 bytes.

![J.Fi](https://jmarple.ai/content/products/j-fi/product.png)

### Network topologies

J.Fi supports 1:1, 1:N, and N:N networks. Time slot-based response delay management prevents collisions in large networks such as drone swarms and robot fleets.

![1:N](https://jmarple.ai/content/products/j-fi/topology-1n.png)
![N:N](https://jmarple.ai/content/products/j-fi/topology-nn.png)
![N:N selective](https://jmarple.ai/content/products/j-fi/topology-nn-selective.png)

### Setup

Two buttons handle pairing and mode switching, and LEDs show the device status. Network settings are configured in a web browser.

## Applications

- Coordinating large groups of UAVs
- Sharing data across robot networks
- Linking IoT sensors and devices

## Specifications

| | |
| --- | --- |
| **Wireless** | |
| Frequency band | 2.4GHz WiFi |
| Speed | 250Kbps to 11Mbps (adjustable) |
| Range | Up to 1 km (depends on environment) |
| Payload | Up to 1024 bytes |
| **Network** | |
| Topologies | 1:1, 1:N, N:N |
| Collision management | Time slot-based response delay |
| **Interface** | |
| Buttons | 2 (pairing, mode switching) |
| LED indicators | Real-time status |
| Configuration | Web browser |
| **Hardware** | |
| Certification | KC Wireless and Wireless EMC (ESP32-WROOM-32UE) |
| Memory | 4MB flash |
| Ports | UART × 2 (JST 6-pin)<br />USB × 1 (Micro 5-pin) |
| Dimensions | 45 × 35 × 10 mm, four 3Φ mounting holes |
| Input voltage | 5V |
| Weight | 8 g |

## Resources

- User manual: [Korean](https://docs.google.com/document/d/1NiXXdwQRQoYMde8sunlQhlv6LxcMnd3FH8WZp9ujinw/edit?usp=sharing), [English](https://docs.google.com/document/d/1NaVwOLuMCuNpd0uxgilXZ_qfHAnsFgBmaPxX9WGY2h4/edit?usp=sharing)
- Pairing example: [YouTube](https://youtu.be/CnjhTfvARmw)
- J.Fi–ROS2 bridge: [GitHub](https://github.com/SUV-Lab/J-Fi)

## Get in touch

J.Fi is sold at [DeviceMart](https://www.devicemart.co.kr/goods/view?no=15648782). For anything else, contact [contact@jmarple.ai](mailto:contact@jmarple.ai).