A system and method for compensating for changes in relative antenna attitude in a single-receiver position detection system, such as a differential carrier phase GPS system, utilizes sensor input to detect changes in the relative attitude of at least two antennas or an antenna positioner, such as an motorized actuator or operator, that orients or re-orients the antennas to a predetermined orientation. The changes in the detected relative carrier phase due to the right hand circular polarized nature of the carrier signals are thus corrected. In this way, the high positional accuracy associated with kinematic GPS systems, for example, can be achieved even when the system's antennas are not constrained by a common rigid body, for example.