An airbag inflator includes non-azide gas generating propellants, surrounding an ignition device, disposed inside a housing. In response to an instruction to start the scanning, the controller forbids the scanner to start the scanning when determining with the ejection detector that a sheet is on the catch tray, and allows the scanner to start the scanning in a selected one of the first mode and the second mode when determining with the ejection detector that no sheet is on the catch tray. An aqueous, non-fluorine-containing binder is used, along with a titanium negative substrate. The principles of this invention are applicable to arrangements with more than two antennas, and an illustrative embodiment is disclosed using the same space block code with two transmit and two receive antennas.