Lenovo TB305XU Limits iBeacon Scan Versus Teclast T50 Mini

Having Android on a tablet does not mean you control Bluetooth Low Energy scan. The app can ask for a continuous iBeacon scan. The tablet firmware still decides how much the radio actually listens. Lenovo TB305XU limits that listen time in firmware. The screen still says Scanning. The packet rate is worse.

‍

twinzo uses Android devices as moving scanners for beacon RTLS. If the tablet drops advertisements, the position stream is worse. We put a Teclast T50 Mini next to a Lenovo TB305XU in the same room, on the same app, and measured it.

‍

Both tablets ran BleScanFast, continuous iBeacon scan, low latency, hardware filter, legacy advertisements only, battery unrestricted. The beacons in the room advertise about every 350 ms. If a scanner kept every blink, one tag would show almost three packets per second. That is the advertising interval yardstick.

‍

Both devices saw about a hundred unique beacons. Last RSSI was almost the same. The radio environment is not the difference.

‍

A callback is one advertisement that reached the app. Do not compare lifetime totals. The Teclast had been scanning longer. Compare packets per second. The T50 Mini delivered a bit more than twice as many iBeacon advertisements to the app as the TB305XU. Short windows (last three seconds, average, peak) show the same gap. The Lenovo is not catching up in bursts.

‍

Packets also arrive later. Average delivery lag is about 20 ms on the Teclast and about 42 ms on the Lenovo, with higher peaks. The app on the Lenovo gets fewer samples, and they are older.

‍

Capture ratio is how many of those 350 ms blinks the tablet handed to the app. The Teclast kept most of them on nearby tags (around two thirds to almost nine in ten). The Lenovo kept about a third to a half on the same tags.

‍

RSSI is how loud each blink sounded. If the Lenovo antenna were worse, the signal would be weaker and unique beacons would drop. They did not. On the same nearby tags the TB305XU often reported a stronger RSSI than the Teclast and still delivered fewer packets. The radio hears the iBeacon. Firmware does not pass advertisements through at the rate the beacon is sending.

‍

Seeing a hundred unique IDs only means each tag was heard at least once. Tracking needs a stream. Unique count on the Lenovo looks fine. Scan rate does not.

‍

Both tablets requested Android SCAN_MODE_LOW_LATENCY. Both used a hardware-offloaded filter. Both had battery unrestricted. Those are the usual software knobs. They were not enough on TB305XU. You cannot fix this with an app update or by granting Bluetooth permissions again. The clip sits in Lenovo firmware on the scan path.

‍

Passive BLE location, including the Android scanner in getting started with RTLS and the forklift BLE tablet setup, assumes the device actually delivers the advertisements. TB305XU does not, compared with T50 Mini, on the same iBeacon field.

‍

T50 Mini: more than twice the packet rate, most of a 350 ms beacon kept, lower delivery lag. TB305XU: about half the rate, about a third to half of the same beacons kept, higher lag, equal or stronger RSSI. Both say Scanning. The firmware is not the same.

‍

If you need a tablet for live BLE position in twinzo, do not assume a Lenovo Android slate will scan iBeacons at full rate. On TB305XU it does not. Get in touch if you want this bench repeated on a device you are buying.

‍