A vehicle orientation detection system, the system comprising: a Global Navigation Satellite System (GNSS) receiver system that comprises at least two GNSS receivers (102-1, 102-2) each adapted to perform carrier phase measurements; an on-board computing device adapted to implement an integer ambiguity resolution function, wherein the integer ambiguity resolution function obtains differenced carrier phase measurements generated from carrier phase measurements measured by the GNSS receiver system; a plurality of aiding sources coupled to the integer ambiguity resolution function, wherein the plurality of aiding sources are adapted to send to the integer ambiguity resolution function attitude measurements from an attitude aiding sensor and baseline length data associated with a distance between antennas (103-1, 103-2) of the at least two GNSS receivers (102-1, 102-2); wherein the integer ambiguity resolution function includes: an initialization logic that is adapted to calculate float ambiguities and covariances based on the differenced carrier phases, the attitude measurements, and the baseline length data; an integer estimation logic that is adapted to perform a plurality of different integer estimation algorithms that each separately calculate candidate solutions to output a set of integer candidate arrays for at least a first baseline between the at least two GNSS receivers (102-1, 102-2) from the float ambiguities and covariances using the plurality of different integer estimation algorithms; a validation logic that is adapted to establish one of the integer candidate arrays to output as resolved integer values associated with at least the first baseline between the at least two GNSS receivers (102-1, 102-2) from the set of integer candidate arrays based at least in part on the attitude measurements and baseline length data from the plurality of aiding sources; and an estimator coupled to the integer ambiguity resolution, wherein the estimator is adapted to generate, based on the resolved integer values and measurements from the GNSS receiver system, an attitude measurement and a heading measurement. a Global Navigation Satellite System (GNSS) receiver system that comprises at least two GNSS receivers (102-1, 102-2) each adapted to perform carrier phase measurements; an on-board computing device adapted to implement an integer ambiguity resolution function, wherein the integer ambiguity resolution function obtains differenced carrier phase measurements generated from carrier phase measurements measured by the GNSS receiver system; a plurality of aiding sources coupled to the integer ambiguity resolution function, wherein the plurality of aiding sources are adapted to send to the integer ambiguity resolution function attitude measurements from an attitude aiding sensor and baseline length data associated with a distance between antennas (103-1, 103-2) of the at least two GNSS receivers (102-1, 102-2); wherein the integer ambiguity resolution function includes: an initialization logic that is adapted to calculate float ambiguities and covariances based on the differenced carrier phases, the attitude measurements, and the baseline length data; an integer estimation logic that is adapted to perform a plurality of different integer estimation algorithms that each separately calculate candidate solutions to output a set of integer candidate arrays for at least a first baseline between the at least two GNSS receivers (102-1, 102-2) from the float ambiguities and covariances using the plurality of different integer estimation algorithms; a validation logic that is adapted to establish one of the integer candidate arrays to output as resolved integer values associated with at least the first baseline between the at least two GNSS receivers (102-1, 102-2) from the set of integer candidate arrays based at least in part on the attitude measurements and baseline length data from the plurality of aiding sources; and an estimator coupled to the integer ambiguity resolution, wherein the estimator is adapted to generate, based on the resolved integer values and measurements from the GNSS receiver system, an attitude measurement and a heading measurement. an initialization logic that is adapted to calculate float ambiguities and covariances based on the differenced carrier phases, the attitude measurements, and the baseline length data; an integer estimation logic that is adapted to perform a plurality of different integer estimation algorithms that each separately calculate candidate solutions to output a set of integer candidate arrays for at least a first baseline between the at least two GNSS receivers (102-1, 102-2) from the float ambiguities and covariances using the plurality of different integer estimation algorithms; a validation logic that is adapted to establish one of the integer candidate arrays to output as resolved integer values associated with at least the first baseline between the at least two GNSS receivers (102-1, 102-2) from the set of integer candidate arrays based at least in part on the attitude measurements and baseline length data from the plurality of aiding sources; and an estimator coupled to the integer ambiguity resolution, wherein the estimator is adapted to generate, based on the resolved integer values and measurements from the GNSS receiver system, an attitude measurement and a heading measurement.