diff --git a/conf/modules/gps_ubx_ucenter.xml b/conf/modules/gps_ubx_ucenter.xml
index 1f2880dfad..b5db81e04e 100644
--- a/conf/modules/gps_ubx_ucenter.xml
+++ b/conf/modules/gps_ubx_ucenter.xml
@@ -24,9 +24,8 @@ Warning: you still need to tell the driver
   <init fun="gps_ubx_ucenter_init()"/>
   <periodic fun="gps_ubx_ucenter_periodic()" start="gps_ubx_ucenter_init()" freq="4." autorun="TRUE"/>
   <makefile target="ap">
-    <raw>
-      ap.CFLAGS += -DGPS_UBX_UCENTER=\"modules/gps/gps_ubx_ucenter.c\"
-    </raw>
+    <file name="gps_ubx_ucenter.c"/>
+    <define name="GPS_UBX_UCENTER"/>
   </makefile>
 </module>
 
diff --git a/sw/airborne/modules/gps/gps_ubx_ucenter.c b/sw/airborne/modules/gps/gps_ubx_ucenter.c
index 83b02aa1ff..52c8bf1598 100644
--- a/sw/airborne/modules/gps/gps_ubx_ucenter.c
+++ b/sw/airborne/modules/gps/gps_ubx_ucenter.c
@@ -28,6 +28,7 @@
  */
 
 #include "gps_ubx_ucenter.h"
+#include "subsystems/gps/gps_ubx.h"
 
 //////////////////////////////////////////////////////////////////////////////////////
 //////////////////////////////////////////////////////////////////////////////////////
diff --git a/sw/airborne/modules/gps/gps_ubx_ucenter.h b/sw/airborne/modules/gps/gps_ubx_ucenter.h
index 843e6c90a2..b0e93bf428 100644
--- a/sw/airborne/modules/gps/gps_ubx_ucenter.h
+++ b/sw/airborne/modules/gps/gps_ubx_ucenter.h
@@ -28,6 +28,8 @@
 #ifndef GPS_UBX_UCENTER_H
 #define GPS_UBX_UCENTER_H
 
+#include "std.h"
+
 /** U-Center Variables */
 #define GPS_UBX_UCENTER_CONFIG_STEPS	  17
 
diff --git a/sw/airborne/subsystems/gps/gps_ubx.c b/sw/airborne/subsystems/gps/gps_ubx.c
index 260ed71983..160042852e 100644
--- a/sw/airborne/subsystems/gps/gps_ubx.c
+++ b/sw/airborne/subsystems/gps/gps_ubx.c
@@ -53,30 +53,7 @@
 #define UTM_HEM_SOUTH 1
 
 
-#define GpsUartSend1(c) GpsLink(Transmit(c))
-#define GpsUartSetBaudrate(_a) GpsLink(SetBaudrate(_a))
 #define GpsUartRunning GpsLink(TxRunning)
-#define GpsUartSendMessage GpsLink(SendMessage)
-
-#define UbxInitCheksum() { gps_ubx.send_ck_a = gps_ubx.send_ck_b = 0; }
-#define UpdateChecksum(c) { gps_ubx.send_ck_a += c; gps_ubx.send_ck_b += gps_ubx.send_ck_a; }
-#define UbxTrailer() { GpsUartSend1(gps_ubx.send_ck_a);  GpsUartSend1(gps_ubx.send_ck_b); GpsUartSendMessage(); }
-
-#define UbxSend1(c) { uint8_t i8=c; GpsUartSend1(i8); UpdateChecksum(i8); }
-#define UbxSend2(c) { uint16_t i16=c; UbxSend1(i16&0xff); UbxSend1(i16 >> 8); }
-#define UbxSend1ByAddr(x) { UbxSend1(*x); }
-#define UbxSend2ByAddr(x) { UbxSend1(*x); UbxSend1(*(x+1)); }
-#define UbxSend4ByAddr(x) { UbxSend1(*x); UbxSend1(*(x+1)); UbxSend1(*(x+2)); UbxSend1(*(x+3)); }
-
-#define UbxHeader(nav_id, msg_id, len) {        \
-    GpsUartSend1(UBX_SYNC1);                    \
-    GpsUartSend1(UBX_SYNC2);                    \
-    UbxInitCheksum();                           \
-    UbxSend1(nav_id);                           \
-    UbxSend1(msg_id);                           \
-    UbxSend2(len);                              \
-  }
-
 
 struct GpsUbx gps_ubx;
 
@@ -267,11 +244,6 @@ void gps_ubx_parse( uint8_t c ) {
   return;
 }
 
-#ifdef GPS_UBX_UCENTER
-#include GPS_UBX_UCENTER
-#endif
-
-
 void ubxsend_cfg_rst(uint16_t bbr , uint8_t reset_mode) {
 #ifdef GPS_LINK
   UbxSend_CFG_RST(bbr, reset_mode, 0x00);
diff --git a/sw/airborne/subsystems/gps/gps_ubx.h b/sw/airborne/subsystems/gps/gps_ubx.h
index dab9de81a5..e2d1c2ce58 100644
--- a/sw/airborne/subsystems/gps/gps_ubx.h
+++ b/sw/airborne/subsystems/gps/gps_ubx.h
@@ -134,5 +134,27 @@ extern void ubxsend_cfg_rst(uint16_t, uint8_t);
     ubxsend_cfg_rst(gps_ubx.reset, CFG_RST_Reset_Controlled);   \
   }
 
+#define GpsUartSendMessage GpsLink(SendMessage)
+
+#define GpsUartSend1(c) GpsLink(Transmit(c))
+#define UbxInitCheksum() { gps_ubx.send_ck_a = gps_ubx.send_ck_b = 0; }
+#define UpdateChecksum(c) { gps_ubx.send_ck_a += c; gps_ubx.send_ck_b += gps_ubx.send_ck_a; }
+#define UbxSend1(c) { uint8_t i8=c; GpsUartSend1(i8); UpdateChecksum(i8); }
+#define UbxSend2(c) { uint16_t i16=c; UbxSend1(i16&0xff); UbxSend1(i16 >> 8); }
+#define UbxSend1ByAddr(x) { UbxSend1(*x); }
+#define UbxSend2ByAddr(x) { UbxSend1(*x); UbxSend1(*(x+1)); }
+#define UbxSend4ByAddr(x) { UbxSend1(*x); UbxSend1(*(x+1)); UbxSend1(*(x+2)); UbxSend1(*(x+3)); }
+#define GpsUartSetBaudrate(_a) GpsLink(SetBaudrate(_a))
+
+#define UbxHeader(nav_id, msg_id, len) {        \
+    GpsUartSend1(UBX_SYNC1);                    \
+    GpsUartSend1(UBX_SYNC2);                    \
+    UbxInitCheksum();                           \
+    UbxSend1(nav_id);                           \
+    UbxSend1(msg_id);                           \
+    UbxSend2(len);                              \
+  }
+
+#define UbxTrailer() { GpsUartSend1(gps_ubx.send_ck_a);  GpsUartSend1(gps_ubx.send_ck_b); GpsUartSendMessage(); }
 
 #endif /* GPS_UBX_H */