Take-Home Trial Comparing Fast Fourier Transformation-Based and Filter Bank-Based Cochlear Implant Speech Coding Strategies

Table 2

Speech coding strategy characteristics.

Strategy	Filter bank	Envelope extraction	Stimulation mode	Range of alpha	# spectral channels	Spacing of filters
HiResolution	Butterworth	HWR + LPF	Monopolar	—	16	Logarithmic
HiResolution FFT	FFT-based filters	Hilbert envelope	Monopolar	0	16	Logarithmic
HiResolution Optima	FFT-based filters	Hilbert envelope	Dual-electrode	0.25–0.75	135	Logarithmic

FFT: fast Fourier transform; HWR: half wave rectifier; LPF: low-pass filter.