Attitude determination with the aid of a triple-antenna GNSS receiver without integer ambiguity resolutions integrated with a low-cost inertial measurement unit

Resolutions of integer ambiguities in GNSS carrier phase measurements may be removed if only fractional parts of single phase differences are used for an attitude determination. But the fractional parts based attitude determination algorithm must be seeded precisely. Low-cost IMU's measurements are used to satisfy this precise seeding requirement. The special design of the GNSS and IMU coupling filter is proposed. This coupling filter allows to build the tri-antenna GNSS+IMU integrated navigation system using two dual antenna GNSS receivers of any type.