Choose drone detection sensors by site conditions, and keep detection separate from counter-drone action

CISA’s November 2025 detection guidance separates drone detection from counter-drone mitigation, compares acoustic, camera, radar and RF sensors, and asks buyers to get legal review, check false-positive rates and fit detection into existing security plans.

Source facts

CISA’s UAS Detection Technology Guidance, dated November 2025, distinguishes detection technology, which detects, tracks or identifies drones, from counter-UAS systems designed to destroy, take over or down a drone. Because some detection technologies monitor communications between a drone and its ground control station, CISA says to consult legal counsel before purchasing or deploying them.

The guidance describes four primary sensor types. Acoustic sensors have a shorter detection range and can be degraded by ambient noise. Camera-based EO/IR sensors rely on clear line-of-sight and need infrared in low light. Radar generally has longer range but likely requires FCC spectrum authorization. RF sensors do not need line-of-sight but generally cannot detect drones that emit no RF.

CISA suggests asking manufacturers for the system’s false positive rate, noting that frequent false detections can cause alert fatigue, and lists Remote ID receivers as an option for reading drone broadcasts. Its process runs from capability requirements to site-appropriate selection to integration into existing security plans.

Applicability

Use this before any drone detection purchase. The guidance is voluntary and does not address mitigation authority; private organizations should assume that disabling or taking over a drone is outside their role unless counsel confirms otherwise.

DSE recommendation

DSE recommends writing site-specific detection requirements and obtaining legal review before requesting vendor quotes for drone detection. State the protected area, the threats of concern, terrain and noise conditions, and who will watch alerts, then compare sensor types against those conditions rather than a brochure range. Require vendors to state false positive rates, coverage maps and spectrum or FAA coordination needs, and plan how detections reach the monitoring desk and the drone-sighting procedure.

Verification

During acceptance, test with an authorized flight at known positions and times, record detections and misses by sensor, and log false alerts for the first month. Confirm counsel’s written approval of the configuration before the system goes live.

Official reference

CISA — Unmanned Aircraft System Detection Technology Guidance for Critical Infrastructure (November 2025). Reviewed October 18, 2026.