RESPITE: The CASA Toolkit Page: Documentation: Block Library Index:GlottalWave


GlottalWave is a periodic signal generator block that can generate a rectilinear approximation to a series of glottal pulses. There are 9 controlling parameters: SAMPLE_RATE, DURATION, FREQ, AMP, initial PHASE, ATTACK, SUSTAIN, DECAY and CLOSED.

SAMPLE_RATE is in units of samples per second, DURATION is measured in seconds, and FREQ in cycles per second. The glottal wave has maximum value of +AMP and a resting value of 0. The initial PHASE is specified in radians where the one complete cycle of the wave has 2 Pi radians (see diagram below).

The parameters ATTACK, SUSTAIN, DECAY and CLOSED specify the relative duration of each stage of the glottal cycle. If they are arranged to sum to 100.0 then each will represent the percentage of the cycle spent in that stage.

Inputs Meaning Sample 1-D frame $\ge$2-D frame
No inputs

Outputs Meaning
out1 generated signal

Parameters Type Default Meaning
SAMPLE_RATE Float - Number of samples per second
DURATION Float - Duration in seconds of signal to generate
FREQ Float - The sawtooth wave frequency
AMP Float 1.0 The sawtooth wave amplitude
PHASE Float 0.0 The initial phase in radians
ATTACK Float - Attack stage duration as percentage of cycle
SUSTAIN Float - Sustain stage duration as percentage of cycle
DECAY Float - Decay stage duration as percentage of cycle
CLOSED Float - Closed stage duration as percentage of cycle

\psfig {figure=graphics/glottalwave.eps,width=0.9\columnwidth}\end{center}\vspace{-4mm}

Documentation for CTKv1.1.4 - Last modified: Thu Jun 28 11:47:21 BST 2001