How to Android BLE Passive scan

[Stanley Kou]

Hello android Gurus,

I want to scan BLE (Bluetooth Low Energy) advertisers passively within my Android App.

But I couldn't found how to do this. I would appreciate if someone could give me some help.

• According Bluetooth 4.0 Core spec, There exists passive scan mode.
  Vol 6 : Core System Package [Low Energy Controller volume],
  Part D:4.1 PASSIVE SCANNING
  https://www.bluetooth.org/DocMan/handlers/DownloadDoc.ashx?doc_id=282159
  "A device can use passive scanning to find advertising devices in the area."

• And also, android has parameter that determines scan type. (Active/Passive)
  http://androidxref.com/4.3_r2.1/xref/external/bluetooth/bluedroid/stack/btm/btm_ble_gap.c#555
  "scan_type: active scan or passive scan"

• Meanwhile, iOS can scan ble advertisers passively. (sadly, background mode only)
  http://lists.apple.com/archives/bluetooth-dev/2012/May/msg00041.html
  "When the app is in the background, iOS performs passive scanning."

But I cannot found whether it is possible to use passive scan mode or not.

Question : Is it possible to use "PASSIVE SCAN" on Android? If it is possible, How to use this feature?

Thanks,

Stanly Kou.