ibeacons sending rssi value of 0
ibeacon, ios
Solution
The `RSSI` is the "received signal strength of the beacon, measured in decibels." Sometimes a beacon listener will find a beacon, but can't actually determine its RSSI. This is why your accuracy is negative. The RSSI is also an average of "the values of the samples received since the range of the beacon was last reported to your app."
A negative value in this property signifies that the actual accuracy could not be determined.
In this case, you are probably about to exit the beacon region, or you are right on the fringe of its range.
Problem
I have 8 iBeacons and i gave them all the same proximityUUID and different major minor values however, when i try to use the phone to find the beacons, some of them send "rssi" value of 0 why is that ? ``` @implementation CLBeacon(description) -(NSString *)stringProximity{ switch (self.proximity) { case CLProximityUnknown: return @"Unknown"; case CLProximityImmediate: return @"less than 0.5 meters away"; case CLProximityNear: return @"0.5<distance<4 meters away"; case CLProximityFar: return @"more than 4 meters away"; } return @""; } -(NSString *)UUIDString{ NSMutableString *string = [[[self proximityUUID]UUIDString]mutableCopy]; [string replaceOccurrencesOfString:@"-" withString:@"-\n" options:0 range:NSMakeRange(0, [string length])]; return string; } -(NSString *)describe{ NSString *contents = [NSString stringWithFormat:@"proximityUUID:%@\nmajor:%@\nminor:%@\naccuracy:%f\nproximity:%@\nrssi:%ld",[self UUIDString],[self major],[self minor],[self accuracy],[self stringProximity],[self rssi]]; return contents; } @end @implementation WBBeaconManager -(id)init{ self = [super init]; if(self){ self.locationManager = [[CLLocationManager alloc] init]; self.locationManager.delegate = self; [self initRegion]; [self locationManager:self.locationManager didStartMonitoringForRegion:self.beaconRegion]; } return self; } - (void)locationManager:(CLLocationManager *)manager didStartMonitoringForRegion:(CLRegion *)region { [self.locationManager startRangingBeaconsInRegion:self.beaconRegion]; } - (void)initRegion { NSUUID *uuid = [[NSUUID alloc] initWithUUIDString:BEACONUUID]; self.beaconRegion = [[CLBeaconRegion alloc] initWithProximityUUID:uuid identifier:BEACONIDENTIFIER]; [self.locationManager startMonitoringForRegion:self.beaconRegion]; } - (void)locationManager:(CLLocationManager *)manager didEnterRegion:(CLRegion *)region { NSLog(@"Beacon Found"); [self makeText:[NSString stringWithFormat:@"entered region:%@",region.identifier ]]; [self.locationManager startRangingBeaconsInRegion:self.beaconRegion]; [self makeText:[NSString stringWithFormat:@"entered region: %@",region.identifier]]; } -(void)locationManager:(CLLocationManager *)manager didExitRegion:(CLRegion *)region { NSLog(@"Left Region"); [self makeText:[NSString stringWithFormat:@"left region:%@",region.identifier ]]; [self.locationManager stopRangingBeaconsInRegion:self.beaconRegion]; [self makeText:[NSString stringWithFormat:@"left region: %@",region.identifier]]; // self.beaconFoundLabel.text = @"No"; } -(void)locationManager:(CLLocationManager *)manager didRangeBeacons:(NSArray *)beacons inRegion:(CLBeaconRegion *)region { CLBeacon *beacon = [beacons firstObject]; for(CLBeacon *b in beacons){ LogInfo(@"%@",[b describe]); } // if(beacon.proximity == CLProximityNear || beacon.proximity == CLProximityImmediate){ [self makeText:[beacon describe]]; // } } -(void)dealloc{ [self.locationManager stopMonitoringForRegion:self.beaconRegion]; [self.locationManager stopRangingBeaconsInRegion:self.beaconRegion]; } @end ``` and here is the log output: ``` proximityUUID:73A7B094-35DD-4B36-A0AA-F11C62E9B4B0 major:0 minor:3 accuracy:-1.000000 proximity:Unknown rssi:0 ```