June 1, 2026
Customer Requirement
A customer working on a professional UAV communication project required a long-distance fiber optic transmission solution with the following specifications:
The customer had already finalized the deployment concept and needed a reliable dual-fiber communication architecture suitable for industrial or long-range drone systems.
Why Use Two Independent Fiber Links in a Drone?
One of the most common questions from drone integrators is:
Q: Why not transmit everything over a single Ethernet link?
In real UAV deployments, control signals and video/data traffic have completely different priorities.
1. Flight Control Signals
Control protocols such as:
require:
Even small transmission interruptions may affect flight stability.
2. Video and Payload Data
4K video streams, AI payloads, mapping sensors and onboard computers generate much larger traffic loads.
If both control and video share the same communication channel, bandwidth congestion or packet buffering may introduce latency spikes.
For this reason, many professional drone systems physically separate:
using dual independent optical fibers.
Actual Solution Used in This Project
The deployed architecture uses:
1. TTL Fiber Optic Module for CRSF / Flight Control
Model: OM610-1V1T TTL Fiber Module
Main task:
Key features:
The module converts TTL serial signals into optical signals and transmits them through single-mode fiber.
This link is dedicated to:
without interference from video traffic.
2. Gigabit Ethernet Fiber Converter for Video Transmission
Main task:
Key features:
The Ethernet fiber converter handles high-bandwidth applications such as:
Q: Is Gigabit Ethernet Enough for 4K Drone Video?
Yes, most UAV 4K video systems use H.264 / H.265 compression encoding.
Typical bitrates are:
even for high-quality streams.
A gigabit optical Ethernet link provides nearly 900Mbps usable throughput, leaving significant bandwidth margin for:
Why the Customer Chose ST Fiber Connectors?
Q: Why use ST instead of SC or LC?
For many industrial and field-deployment projects, ST connectors are preferred because:
This makes ST connectors practical for:
Typical UAV Applications for Dual Fiber Links
This type of architecture is commonly used in:
Fiber optic communication provides major advantages over traditional RF links:
Final Deployment Structure
The final customer solution uses:
This architecture significantly improves communication reliability and is especially suitable for professional UAV platforms operating in complex electromagnetic environments.
Frequently Asked Questions (FAQ)
Q: Can the TTL optical module support CRSF?
Yes. The module supports TTL UART communication and is suitable for CRSF transmission used in FPV and professional UAV systems.
Q: Can the Ethernet converter transmit 4K video?
Yes. Gigabit Ethernet bandwidth is fully sufficient for compressed 4K H.264/H.265 video streams.
Q: What transmission distance is supported?
Optional distances include:
depending on optical configuration.
Q: Can the system work directly from drone batteries?
Yes. Both modules support wide DC voltage input and can be powered directly from UAV battery systems.
Q: Why separate control and video links?
Because flight control requires ultra-low latency and high stability, while video traffic consumes much larger bandwidth. Physical isolation improves reliability and prevents interference between signal types.
