如何使用android studio计算ibeacon的距离

<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />

BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

bluetoothAdapter.startLeScan(new BluetoothAdapter.LeScanCallback() {
    @Override
    public void onLeScan(final BluetoothDevice device, int rssi, byte[] scanRecord) {
        // 处理扫描结果
    }
});

// 解析UUID
ByteBuffer bb = ByteBuffer.wrap(scanRecord);
bb.order(ByteOrder.LITTLE_ENDIAN);
while (bb.remaining() > 2) {
    byte length = bb.get();
    if (length == 0) break;

    byte type = bb.get();
    switch (type) {
        case 0x02: // Partial list of 16-bit UUIDs
        case 0x03: // Complete list of 16-bit UUIDs
            while (length >= 2) {
                UUID uuid = UUID.fromString(String.format(
                        "%08x-0000-1000-8000-00805f9b34fb", bb.getShort()));
                // 处理UUID
                length -= 2;
            }
            break;
        case 0x06: // Partial list of 128-bit UUIDs
        case 0x07: // Complete list of 128-bit UUIDs
            while (length >= 16) {
                long lsb = bb.getLong();
                long msb = bb.getLong();
                UUID uuid = new UUID(msb, lsb);
                // 处理UUID
                length -= 16;
            }
            break;
        default:
            bb.position(bb.position() + length - 1);
            break;
    }
}

double distance = Math.pow(10, (txPower - rssi) / (10 * 2.0));