Is iBeacon detection within another iBeacon range possible? BLE - bluetooth-lowenergy

Question

iBeacon Question. Is this possible ..
Can I have 4 iBeacon’s that are used on the corners of a stage that is say 10ft by 25ft. This is used so I can detect this stage area in the App. (Are 4 iBeacon’s needed to do this or can it be done with 3?)
I Then need the App to detect 2 things ...
The app needs to detect if it’s inside or outside of the area, and how close it is to the area it is outside of, and on what side of the area it is.
If a 5th iBeacon is brought inside the area, can the app detect that there is a separate iBeacon that is within the stage area setup by the previous 4 iBeacon’s.
E.g. You App tells you there is a stage in front and where in relation to the stage you are by using the 4 iBeacon’s. The app then tells you that there is now another 5th iBeacon has entered the stage and where it is on the stage. The App can then detect that the 5th iBeacon has now left the stage.
Is this possible???

Answer 1

Yes you can, as long as each beacon has a unique identifier. Most likely I would configure the beacons to:
Have the same UUID
Have the same Major
Have a unique Minor
If you use CoreLocation's locationManager:didRangeBeacons:inRegion: the delegate will give you a callback with all the beacons it can see at a current time. You can use this to track your own list of beacons and see if a new beacon has appeared.
Example code might look like this:
- (void)locationManager:(CLLocationManager *)manager
didRangeBeacons:(NSArray *)beacons
inRegion:(CLBeaconRegion *)region
{
for (CLBeacon *beacon in beacons)
{
// TODO: Handle each beacon logic here
}
// TODO: Clean up any stale beacons here (e.g. remove old beacons)
}
```

Answer 2

csexton's answer is correct in terms of ranging multiple beacons, but you may have difficulty using multiple beacons to accurately determine a position in a 10'x25' stage.
iBeacon distance calculations are based on received signal strength and is affected considerably by things that absorb the radio signal - such as people. The iPhone doesn't have a directional bluetooth antenna so it can't triangulate the received signals, so this means if the beacon on, say, the left edge of the stage is being received the app won't know whether the device is on the stage, to the right of the iBeacon, or off the stage in the audience.
I guesss all you can do is try.