“Which drone detection technology should I buy?” is the wrong first question. The right one is “what does my site need to see, and what can it afford to miss?” This article walks through that decision site-type by site-type, with budgets, evidence labels and the combinations that actually make sense. It goes deeper than our earlier primer on the three technologies — this one is for people close to a purchase.
The three layers, one line each
Remote ID (RID) receivers hear the standardised broadcast that most drones sold since 2024 must carry: identity, position, take-off point. RF spectrum sensors hear any transmitter — including FPV builds and modified aircraft that broadcast nothing. Radar sees airframes whether they transmit or not, at the highest cost. Prices we quote across the site, all vendor-reported: RID $129–2,500 per node, RF $3,500–15,000, radar from roughly $50,000 upward for a usable installation.
How we structured this comparison
Method: we match detection layers against site types using three inputs — the threat models that dominate each site category, the published capability and cost data on our receiver comparison, and the survey discipline in our checklist. We do not score radar (outside our advisory scope) beyond noting where it belongs. Treat every budget as vendor-reported; treat the mapping as our judgement, not physics.
Site type by site type
- Prisons and secure facilities — the confirmed threat is contraband drops, often flown on home-built quads. RID alone undercovers; the RF layer is not optional. Start RID (cheap baseline), add RF on approach corridors.
- Airports and airspace — the fleet is mostly compliant consumer and commercial aircraft. RID receivers carry most of the load; RF and radar are regulator-grade additions. Your aviation authority will have opinions — involve them early.
- Events and stadiums — short deployments, dense RF, heavy media drones that do broadcast. RID-first works; RF earns its cost only for A-list threat profiles. Renting beats buying for one-off events.
- Critical infrastructure — mixed fleet, long perimeter, 24/7 operation. The RID + RF combination is the honest default; budget for two nodes minimum and a validation walk-test.
- Law enforcement — you need identification for response, which makes RID’s decoded identity (serial, operator position) uniquely valuable; RF adds the silent-aircraft picture. Evidence handling rules push toward logged, timestamped data — both layers provide it.
Where buyers go wrong
The recurring failure is buying the impressive layer instead of the correct one: radar dreams on a RID budget, or an RF sensor deployed where every detection is a false alarm because the site’s own Wi-Fi drowns 2.4 GHz. The second failure is skipping phase zero — two weeks of baseline logging answers more questions than any datasheet.
| Site | Start with | Add if | Skip for now |
|---|---|---|---|
| Prison | RID baseline + RF | Radar at state level | Radar-only |
| Airport | RID receiver grid | RF for known silent traffic | DIY anything |
| Event | RID (rented) | RF for A-list events | Purchases |
| Infrastructure | RID + RF two-node | Correlation service | Single-layer promises |
| Law enforcement | RID for identification | RF vehicle unit | Fixed install before pilots |
Where to go next: run your site through the survey checklist, compare hardware on the receiver table, or hand the question to us with the free screening.
Content last reviewed: 2026-09-11. Budgets are vendor-reported, checked September 2026. This is advisory content, not a quotation.