Umbra Link — Covert DSSS Datalink for Drones
Umbra Link is elexResearch’s covert below-noise-floor LPD/DSSS datalink for drone C2—in active development; early access for Indian OEMs. Not a shipped product.
# Umbra Link
A drone datalink that’s invisible before it’s ever jammed.
Most anti-jam radios survive interference by hopping to a clear channel — the signal is still there to be found, it just moves. Umbra Link is being built on a different principle: the signal stays buried below the noise floor, so there’s nothing for a jammer or a passive intercept receiver to find in the first place.
Status: in active development. This page describes what we’re building and why — not a shipped product. We’re opening early access to a small number of Indian drone manufacturers ahead of the first validated units.
What it is
Umbra Link is a covert (low-probability-of-detection) RF datalink for drone telemetry and video, developed in our RF lab in Indore. The validation program is running now — real hardware, real spectrum-analyzer measurements — not a simulation or a slide deck.
Why it’s different
Frequency-agile anti-jam radios already exist and work well for their purpose — when interference is detected, they hop to a cleaner channel. That solves jamming. It doesn’t solve detection: the radio is still findable, it’s just relocating.
Umbra Link targets the other threat model — staying undetected in the first place, which matters against targeted jamming and passive SIGINT/geolocation, not just barrage interference.
Target specifications
(Targets for the current development program — not yet independently verified; will be updated with measured bench results as each phase completes.)
| Spec | Target |
|---|---|
| Detection resistance | Signal held below the measured noise floor — target SNR margin TBD, pending bench validation |
| Jamming margin | Target dB above ambient — TBD, pending bench validation |
| Payload | Telemetry now; video in a later development phase |
| Spectrum | India’s license-exempt bands (2.4/5.8 GHz) — no WPC licensing burden for the integrator |
Who this is for
Indian drone manufacturers building for defense, security, or BVLOS applications where link detectability — not just link reliability — is part of the threat model.
Request the technical brief
We’re talking to a small number of manufacturers before the first validated units are ready. If detection/jamming resistance matters for your platform, request the brief and we’ll follow up directly — no purchase, no commitment, just a real conversation about whether this is relevant to what you’re flying.
Request the technical brief →
(name / company / platform / email)