In this paper the problem of optical distance measurements is considered. The proposed measurement system is based on the FMCW (frequency modulated continuous wave) method. A measurement acquisition system is realized from which the real data are collected. This system represents a two target scenario. After deriving a simple signal model for multi-target scenarios two different distance estimation procedures are introduced, a Fourier-based and a subspace algorithm. The signal model is verified using both simulated and measured data. Distance measurements are performed for real and synthetic data to investigate the performance of the measurements. It is known that the significant difference between the two algorithms is the resolution capability. Therefore, we investigate the case of closely spaced targets. In addition we study the performance for well separated targets concerning bias and variance.