Resolving ambiguities The range accuracy will be low for long wavelength modulation: Rule of thumb: Phase can be measured to about 1% of wavelength For EDM: Use multiple wavelengths each shorter using longer wavelength to resolve integer cycles(example next slide) Using this method EDM can measure 10s of km with millimeter precision 02/2502 12.540Lec06 1902/25/02 12.540 Lec 06 19 Resolving ambiguities • The range accuracy will be low for long￾wavelength modulation: Rule of thumb: Phase can be measured to about 1% of wavelength • For EDM: Use multiple wavelengths each shorter using longer wavelength to resolve integer cycles (example next slide) • Using this method EDM can measure 10’s of km with millimeter precision