diff --git a/owlps-positioning/src/inputudpsocket.cc b/owlps-positioning/src/inputudpsocket.cc
index 174804d..69bfa2f 100644
--- a/owlps-positioning/src/inputudpsocket.cc
+++ b/owlps-positioning/src/inputudpsocket.cc
@@ -149,6 +149,15 @@ const Request& InputUDPSocket::get_next_request()
   if (request.type == OWL_REQUEST_CALIBRATION ||
       request.type == OWL_REQUEST_AUTOCALIBRATION)
     {
+      AccessPoint &transmitter =
+        const_cast<AccessPoint&>(Stock::find_create_ap(mac_mobile)) ;
+
+      // If an autocalibration request does not contain the coordinates
+      // of the AP, we use the current coordinates of the AP as
+      // ReferencePoint.
+      if (request.type == OWL_REQUEST_AUTOCALIBRATION && ! position)
+        position = transmitter.get_coordinates() ;
+
       const ReferencePoint &reference_point =
         Stock::find_create_reference_point(position) ;
       current_request_to_calibration_request(&reference_point,