Capturing data packets from beacon using Altbeacon - android

I've a specific beacon that transmits data packets. I can see that Altbeacon library recognises this beacon (from minorId) and I can see that packetCount is 1, but what I cannot see is packet itself (from Beacon object). How can I do that? How can I get Beacon advertisement bytes - I know I can use setDebug(true) to see them in console, but is it possible to retrieve it in code programatically? How? Thanks in advance.

Beacon sends three things which you can capture using functions like beacon.getId1() which is UUID, beacon.getId2() which is major and getId3() which is minor.

Related

To get Tx Power of BLE Beacon in Android

What I Know is,
Broadcasting Power (or Transmit Power) is the power with which the beacon broadcasts its signal. The maximum range of the broadcast signal depends on this.
As I was going through the Kontakt.io blog they says that, Tx power level can be adjusted by the user whose value varies between 0-7(in case of Kontakt beacons & can be different for other beacons). For more info please go through
this link.
The advertising packets sent by beacon contains the information about calibrated Tx Power(RSSI power value at 1 meter).
My question is that,
Is it possible to get broadcasting power , the signal power that beacon sends from the source (as mentioned above the value varies between 0-7) (not the calibrated Tx Power) from BLE APIs?
I had observed that result returned by the toString() method of ScanResult class contains mTxPowerLevel which is same for different beacons(mTxPowerLevel=-2147483648).
My other question is that, what is this mTxPowerLevel?
If my way of understanding is wrong, please guide to go in a right direction. Thank you!!
learner,
Using the Kontakt.io Android SDK you can receive this value from range 0-7 (or in case of Beacon Pros 1-7). Here you can find the Quickstart guide for the newest right now SDK 3.2.1.
Here you can find how to implement simple ranging for the beacons on Android.
Let it be that your beacons broadcast the iBeacon packet, so using iBeacon Listener when you discover the beacon simply use
ibeacon.getTxPower()

BLE Beacon with custom data broadcasting

In the application I am looking forward Bluetooth in Beacon is very good option as I want to collect PH from different sources to the application so I can't pair my android device with all the BLE devices at a time as it will be around 20-30.
But I can see that if there is Beacon then Android can scan all of them and also get the RSSI of all devices without being paired with them.
So is it possible that we add few other parameter for example PH, Temperature, Humidity and 3-4 other parameters so Beacon is going to broadcast all these parameter along with RSSI and in Android app I can collect all the information?
I am not sure if this is feasible solution or not and if it is then how to achieve this in beacon?
Bluetooth beacons generally rely upon advertisement packets to send data, which are limited in the number of bytes available. For manufacturer advertisements, you basically have 24 usable bytes to work with, although you need to reserve some of these as a flag to indicate it is your beacon format, and not somebody else's beacon format.
You can look at the AltBeacon spec as an example. This format uses two bytes to identify itself (the "beacon code"), 20 bytes of beacon identifiers, one byte of data and one byte for reference RSSI. You probably still want a unique identifier for each beacon so you know which beacon sent you the information. But you might be able to cut this down to four bytes for your purposes, which would allow you to have 2^32 different beacons sending this information.
The Android Beacon Library lets you both transmit and receive beacons using arbitrary formats you can define using the BeaconParser class. A beacon format that uses a four byte identifier, two bytes each for PH, Temperature and Humidity data fields, and two bytes each for five other data fields might look like this:
m:2-3=abcd,i:4-7,d:8-9,d:10-11,d:12-13,d:14-15,d:16-17,d:18-19,d:20-21,d:22-23,p:24-24

How much amount of arbitrary data can be included in Beacon PDU?

We're trying to emulate a beacon on a Android device and would like to include some 50 bytes of application data in payload? We found that with AltBeacon format this is not possible? How can it be done with help of AltBeacon lib for Android?
Moreover, what are primary and secondary beacon advertisements?
What is role of GattBeacon in this context and when and how should it be used?
There are two basic types of BLE beacon advertisements:
Manufacturer advertisements (iBeacon, AltBeacon, Gimbal)
GATT Service Advertisements (Eddystone, UriBeacon, GattBeacon)
They differ mainly by the bluetoorh PDU type, but in both cases the number of bytes that can be transmitted are similarly limited. It is 23 bytes for manufacturer advertisements (not counting the two byte manufacturer code).
With Bluetooth 4.x, you just won't get close to 50 bytes in a single packet. Bluetooth 5.0 is expected to increase this at some point in the future.
None of the beacon layouts let you go beyond this limit. GattBeacon is merely a generic example layout of a beacon based on GATT Service advertisements, and is not meant for practical use.

Android Bluetooth Low Energy - iBeacon

Recently I got a iBeacon device with the intention of creating Android Apps than can recognize it and use it. I'm new using bluetooth in Android Apps and there many things than I still don't know. Looking in the Internet and in this forum I found recommendations to use the Radius Networks' Android IBeacon Library but, alas, now it's no longer available:
https://github.com/RadiusNetworks/android-ibeacon-service
So I started by using the code shown in Android Developers' guide about Bluetooth Low Energy:
https://developer.android.com/guide/topics/connectivity/bluetooth-le.html
Using this code I can detect the device, even connect to it, but I don't know how to get the Proximity Uuid and the Major and Minor values: the app shows a lot of Uuids from services and characteristics of the device, but none is the Proximity Uuid of the device.
Anyone could tell me how to get that data using the Android Bluetooth LE API, or help me to get the Radius Networks' Android iBeacon library for Eclipse and a guide to use it or sample showing how to use it?
Thank you.
EDIT/UPDATE:
It gets better.. AltBeacon !
Check the AltBeacon specifications
AltBeacon brings greater transparency to what a beacon transmits and
how that data can be used by Android, Windows and other devices.
Why the Android iBeacon Library by RadiusNetworks is no longer available:
Vendors have started complying with guidelines set by Apple and have,
as a result, been forced to ‘scrub’ their products of any references
or connection between Android devices and their detection of iBeacon
protocols.
Read more:
Apple cracks down on iBeacon for Android
I think the best bet seems to be from somebody who has been using it, already has it, can share it with you, as from previous commits, you may not get every component - library, sample, service
Also: A note from the CEO for Android iBeacon Lib, RadiusNetworks
Now, coming to Proximity UUID and major, minors:
I have not found a direct way to get it, in terms of a parameter, though you can have a look at read major, minor, uuid of beacons in android and SensorTag using iBeacon Technology. In the latter, there is an indication of major, minor, uuid after iBeacon Service, however TI instruments might be the restriction.
In android, as an identifier.. you can recover the device addressby device.getAddress() of the beacon/for each BluetoothDevice device;.
The following two are totally different things, although both are called UUID.
UUIDs of GATT services which are hosted on a BLE peripheral device.
Proximity UUID of iBeacon.
What you should know about "UUIDs of GATT services":
BLE peripheral devices may implement a GATT server.
A GATT server hosts GATT services.
What the API "android.bluetooth.BluetoothGatt.getServices()" returns is a list of GATT services (List<BluetoothGattService>).
BluetoothGattService.getUuid() returns the ID of the service.
What you should know about "Proximity UUID of iBeacon":
BLE peripheral devices broadcast advertising packets.
The payload part of an advertising packet contains a list of AD structures.
An AD structure consists of (1) Length (1 byte), (2) AD Type (1 byte) and (3) AD Data. The AD structure format is described in "11 ADVERTISING AND SCAN RESPONSE DATA FORMAT" of "Bluetooth Core Specification 4.2".
iBeacon is a kind of AD structures.
AD Type of iBeacon is 0xFF (which means Manufacturer Specific Data).
The first 4 bytes of AD Data of iBeacon are 0x4C, 0x00, 0x02 and 0x15. The first 2 bytes (0x4C, 0x00) mean "Apple, Inc." and the next 2 bytes (0x02, 0x15) mean "iBeacon format".
Proximity UUID (16 bytes), major number (2 bytes in big endian), minor number (2 bytes in big endian), and power (1 byte) follow the first 4 bytes.
So, what you have to do to get iBeacon information (Proximity UUID, major, minor, power) are as follows.
Parse a payload of an advertising packets as a list of AD structures.
For each AD structure, check if AD Type is 0xFF and the first 4 bytes of AD Data are 0x4C, 0x00, 0x02 and 0x15.
When the conditions of 2. are satisfied, parse the remaining bytes as Proximity UUID, major number, minor number, and power.
If you use nv-bluetooth, you can extract iBeacon from an advertising packet like the following:
public void onLeScan(BluetoothDevice device, int rssi, byte[] scanRecord)
{
// Parse the payload of the advertising packet.
List<ADStructure> structures =
ADPayloadParser.getInstance().parse(scanRecord);
// For each AD structure contained in the advertising packet.
for (ADStructure structure : structures)
{
if (structure instanceof IBeacon)
{
// iBeacon was found.
IBeacon iBeacon = (IBeacon)structure;
// Proximity UUID, major number, minor number and power.
UUID uuid = iBeacon.getUUID();
int major = iBeacon.getMajor();
int minor = iBeacon.getMinor();
int power = iBeacon.getPower();
........
See "iBeacon as a kind of AD structures" for details.
RadiusNetworks has "re-released" the libraries and examples in conjunction with a new cross platform beacon proximity spec.
New AltBeacon Standard Allows Cross-Platform Proximity Apps
Check out altbeacon.org.

Android iBeacon Library fromScanData returning null always

I have been trying to write an application to detect iBeacons. (I set up my iPhone 5 as iBeacon)
I slightly changed the fromScanData method to return only proximity UUID String. I have no idea how the pattern detection works. It always Logs "This is not an iBeacon advertisement".
I am not using the whole IBeacon class. I am using the method alone. I am calling it from my
onLeScan and passing the byte array scanRecord, rssi value and the BluetoothDevice object.
Once I have my proximity UUID for each ble device, I can filter the ones I want.
Please help. Thanks in advance.
The Log
04-17 14:44:29.828: D/BLEScan(28549): This is not an iBeacon advertisment (no 0215 seen in bytes 4-7).The bytes I see are :02011a0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
The debug line says it all. Those bytes do not indicate a valid iBeacon advertisement. Are you sure your iPhone transmitter is really working properly? Can you detect the iBeacon using a different tool like the Android iBeacon Locate app?
I don't know how you set up the transmitter but you might also try Locate for iBeacon iOS app or EZ Beacon iOS app, which are known to transmit properly formed iBeacon advertisements that work with this code. The same Android code is inside the iBeacon Locate app.
Finally, make sure your iPhone transmitter is in the foreground. iOS devices cannot transmit as iBeacons in the background.

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