There is provided a signal generating apparatus including: a multiphase oscillating portion for generating a number of base signals having the same frequency and a predetermined phase difference of which the signal level transitions between a first level and a second level, and where periods during which the signal level of any given base signal is at the first level and the signal level of the next base signal having the predetermined phase delay relative to the given base signal is at the first level overlap; and a transition time point changing portion for generating a pulse signal by changing the time point when each base signal transitions from the first level to the second level to a time point before the next base signal transitions from the second level to the first level.