In this paper, we propose the attitude determination algorithm to design MATLAB based GPS compass system by using low cost GPS receivers. Two integer ambiguities search method are considered: LAMBDA, BC LAMBDA. And to verify suitability of the low cost receiver for the algorithm, Zero base line test was conducted. We found a TTM problem in low cost receiver, and compensated carrier phase measurement with the method which was developed by Korea Aerospace Univ. Also, the implemented system has been evaluated by comparing results of the computed attitudes using mid-end GPS and high-end GPS. Real time operation of the system was verified through several experiments.

Keywords: GPS, CDGPS, LAMBDA, BC LAMBDA, MATLAB, GPS COMPASS