diff --git a/libraries/AP_Beacon/AP_Beacon_Backend.cpp b/libraries/AP_Beacon/AP_Beacon_Backend.cpp
index d91e5dea8b..07cc8979f7 100644
--- a/libraries/AP_Beacon/AP_Beacon_Backend.cpp
+++ b/libraries/AP_Beacon/AP_Beacon_Backend.cpp
@@ -26,8 +26,8 @@ AP_Beacon_Backend::AP_Beacon_Backend(AP_Beacon &frontend) :
 {
 }
 
-// set vehicle position:
-// pos should be in the beacon's local frame in meters
+// set vehicle position
+// pos should be in meters in NED frame from the beacon's local origin
 // accuracy_estimate is also in meters
 void AP_Beacon_Backend::set_vehicle_position(const Vector3f& pos, float accuracy_estimate)
 {
@@ -36,7 +36,7 @@ void AP_Beacon_Backend::set_vehicle_position(const Vector3f& pos, float accuracy
     _frontend.veh_pos_ned = correct_for_orient_yaw(pos);
 }
 
-// set individual beacon distance in meters
+// set individual beacon distance from vehicle in meters in NED frame
 void AP_Beacon_Backend::set_beacon_distance(uint8_t beacon_instance, float distance)
 {
     // sanity check instance
@@ -54,8 +54,8 @@ void AP_Beacon_Backend::set_beacon_distance(uint8_t beacon_instance, float dista
     _frontend.beacon_state[beacon_instance].healthy = true;
 }
 
-// configure beacon's position in meters from origin
-// pos should be in the beacon's local frame (meters)
+// set beacon's position
+// pos should be in meters in NED from the beacon's local origin
 void AP_Beacon_Backend::set_beacon_position(uint8_t beacon_instance, const Vector3f& pos)
 {
     // sanity check instance
diff --git a/libraries/AP_Beacon/AP_Beacon_Backend.h b/libraries/AP_Beacon/AP_Beacon_Backend.h
index 905c9d14a3..20f6f24a4a 100644
--- a/libraries/AP_Beacon/AP_Beacon_Backend.h
+++ b/libraries/AP_Beacon/AP_Beacon_Backend.h
@@ -31,14 +31,16 @@ public:
     // update
     virtual void update() = 0;
 
-    // set vehicle position, pos should be in the beacon's local frame
+    // set vehicle position
+    // pos should be in meters in NED frame from the beacon's local origin
+    // accuracy_estimate is also in meters
     void set_vehicle_position(const Vector3f& pos, float accuracy_estimate);
 
-    // set individual beacon distance in meters
+    // set individual beacon distance from vehicle in meters in NED frame
     void set_beacon_distance(uint8_t beacon_instance, float distance);
 
-    // configure beacon's position in meters from origin
-    // pos should be in the beacon's local frame
+    // set beacon's position
+    // pos should be in meters in NED from the beacon's local origin
     void set_beacon_position(uint8_t beacon_instance, const Vector3f& pos);
 
     float get_beacon_origin_lat(void) const { return _frontend.origin_lat; }
diff --git a/libraries/AP_Beacon/AP_Beacon_SITL.cpp b/libraries/AP_Beacon/AP_Beacon_SITL.cpp
index 2aa0af5b67..83dfbf2cfe 100644
--- a/libraries/AP_Beacon/AP_Beacon_SITL.cpp
+++ b/libraries/AP_Beacon/AP_Beacon_SITL.cpp
@@ -108,7 +108,6 @@ void AP_Beacon_SITL::update(void)
     set_beacon_distance(beacon_id, beac_veh_offset.length());
     set_vehicle_position(veh_pos3d, 0.5f);
     last_update_ms = now;
-
 }
 
 #endif // CONFIG_HAL_BOARD