1. Broadcast
The beacon sends an advertising event on primary channels 37, 38, and 39. Receivers may miss one copy and still catch another.
BLE Beacon Broadcast Workbench
Compare iBeacon and Eddystone frames while BLE advertisements move across channels 37, 38, and 39.
animation
bluetooth
ble
beacons
short-range
Interactive BLE beacon animation showing legacy advertising channels, iBeacon UUID/Major/Minor fields, Eddystone UID/URL/TLM/EID frame choices, RSSI proximity zones, advertising interval tradeoffs, and deployment pitfalls.
BLE Beacon Broadcast Workbench
Watch a beacon advertise a small frame without forming a connection. Compare iBeacon and Eddystone choices, then test how distance, interval, and the room affect what a phone or gateway can infer.
Frame
iBeacon
Current Channel
37
Proximity
Near
Scenario Fit
92/100
2. Decode
The app or gateway reads the frame type and fields. iBeacon identifies regions; Eddystone can carry identifiers, URLs, telemetry, or ephemeral IDs.
3. Estimate
RSSI and the calibrated 1 m value support a proximity zone. They do not produce a precise indoor coordinate.
4. Design
Use the scenario fit and warning to choose the frame, interval, and maintenance plan that match the learning objective.
Advertising Event Trace
A legacy BLE beacon repeats a compact payload on the three primary advertising channels.
Legacy advertising
RSSI zone only
1. Packet
iBeacon
Region ID
2. Channel
Ch 37
Primary advertising lane
3. Receiver
Near
-68 dBm estimate
RSSI Estimate
-68 dBm
Discovery
Fast
Battery Cost
Balanced
Payload Role
Region ID
BLE Beacon Quick Reference
Beacon, Not Connection
A beacon normally broadcasts one-way advertising data. It does not need pairing, a GATT session, or an acknowledgement from the receiver.
37, 38, 39
Legacy BLE advertising sends copies on the three primary advertising channels. This improves discovery in noisy 2.4 GHz spaces.
UUID, Major, Minor
The common pattern is a shared deployment UUID, a Major group, a Minor item, and a measured-power calibration value.
UID, URL, TLM, EID
UID identifies, URL points to a web resource, TLM reports health, and EID rotates for privacy-sensitive identification.
Legacy Size Limit
Classic legacy advertising has a small AdvData budget. Good beacon designs encode a compact key and look up richer content elsewhere.
Zone, Not Exact Range
Walls, bodies, orientation, and multipath change received signal strength. Treat the result as immediate, near, far, or unknown.
Speed Vs Battery
Short intervals improve discovery latency but spend more energy. Long intervals last longer but can feel slow to moving users.
Static IDs Are Observable
Anyone scanning can observe static identifiers. Avoid putting user data in a beacon frame and rotate identifiers when privacy requires it.
Learning Support
How To Read The Animation
The active lane shows which advertising channel is carrying the current event. The moving packet is the beacon payload. The receiver card shows what the app or gateway can infer.
What To Try First
Switch from iBeacon to Eddystone TLM in the museum scenario. The score drops because telemetry is useful for maintenance, but it does not identify an exhibit by itself.
Common Learner Mistake
Do not treat RSSI as a tape measure. It is normal for a farther beacon with a clearer path to appear stronger than a nearer blocked beacon.
Technical Accuracy Notes
Legacy Advertising Model
This page focuses on legacy BLE advertising because iBeacon and the classic Eddystone frames fit that teaching model. Bluetooth 5 extended advertising can carry more data and uses secondary channels differently.
Calibration Value
The 1 m value is a measured RSSI calibration used by receiver software. It is related to the installed beacon and environment, not a promise of exact distance.
Eddystone Status
Google's Eddystone repository is archived, but the frame definitions remain useful for teaching beacon frame design and historical deployments.