Figure 9.

The auditory radar-detected time-varying vocal folds vibration frequency of the continuous speech signal, ’/q$\check{\mathrm{i}}$ng zh$\stackrel{`}{\mathrm{u}}$ y$\stackrel{`}{\mathrm{i}}$ $\overline{\mathrm{a}}$n qu$\acute{\mathrm{a}}$n/’. The "×" symbols represent the hand-labeled acoustic fundamental frequency values.