Radio analysis apparatus and method

A radio analysis apparatus includes: a processor that calculates a modulation index of a radio signal generated by performing frequency shift keying on a baseband signal, based on phase shift amounts of the radio signal; and a memory that holds information in which bit patterns of the baseband signal are associated with correction values for correcting the phase shift amounts that have dropped by band limitation on the baseband signal. The processor restores the bit patterns of the baseband signal based on the phase shift amounts of the radio signal, corrects the phase shift amounts of the radio signal by using the correction values corresponding to the restored bit patterns, and calculates the modulation index based on the corrected phase shift amounts.