Acceptable fallback options for cell and WLAN positioning. Values area and any apply to cell based positioning only in case none of the models of the cells serving the target device are currently available. Value singleWifi applies to WLAN based positioning in case only one of the provided WLAN APs can be used for position calculation.
By default, cell based positioning returns only cell level location estimates. In LTE and LTE Cat-M, use the fallback=area setting if you permit location estimate to be based on a combination of cells of a single tower, or more precisely, on an eNodeB area. Also use this setting if you allow location estimate to be based on an area of a group of cells defined by the network (LAC, RNC, TAC, NID, or RZ). If you use the fallback=any setting, the service can use all aforementioned cell fallback methods and additionally fallback to the MNC, SID, or MCC level. If both area and any are specified, then area is ignored.
For privacy reasons, the precise positioning based on a single WLAN AP is not possible. You can use the fallback=singleWifi setting to allow less accurate positioning based on a single WLAN AP. In that case, the center location of the position estimate will be deviated and the reported accuracy radius will be larger. If you choose to make use of this parameter, it is recommended to use it in all requests, not only those which contain just single WLAN AP measurement. This will help to avoid error responses with status 400 in cases when all APs except one have either multicast MAC address (which are excluded from positioning) or are otherwise unusable for position calculation.
