The invention includes a method and system for intra-operative navigation of a joint replacement operation, without recourse to pre-operative imagery of pre-operative computerized simulations. The collimator receives reflected light beams from the optical pickup head and generating images from the reflected light beams. The transceiver is adapted to enable wireless communication between each transponder or transponderreceptor unit and the computer manager system within a distance that is within a range detectable by said transponderreceptor units and the computer manager system. 5 to 10% of at least one wax,0 to 3. The method and system include acquiring measured information for at least one pulse at a pressure step, determining and storing quality values for the at least one pulse at the pressure step, analyzing pulse matching criteria for the pressure step, and determining pulse rate based on the measured information, quality values, and pulse matching criteria. At each depth of interest, it is then possible to obtain a dispersion curve of greatest semblance.