介绍一个线性调频扫频正弦发生器。
安装
进入REPL模式并通过以下方式从最新存储库中添加模块：
]add https://github.com/sonosole/ChirpSignal.git
或者从julia的官方仓库：
]add ChirpSignal
两个公共API
chirp(T, fs, fl, fh; method="linear", phase=0.0) -> Array{Float64,1}
chirp(T, fs, f::Function; phase::Real=0.0) -> Array{Float64,1}
示例
using WAV
using ChirpSignal
fs = 16000.0; # sampling frequency
fl = 500.0; # lower bound frequency
fh = 8000.0; # upper bound frequency
T = 5.0 ; # total time of chirp signal
线性
# f(t) = (fh-fl)/T * t + fl
wav = chirp(T, fs, fl, fh; method="linear");
wavwrite(wav, "./doc/chirpLinear.wav", Fs=fs, nbits=32)
二次型
# f(t) = k * t^2 + fl, k = (fh-fl)/T^2
wav = chirp(T, fs, fl, fh; method="quadratic");
wavwrite(wav, "./doc/chirpQuadratic.wav", Fs=fs, nbits=32)
自定义示例
用户自己定义频率随时间的变化函数，例如这里的 fun(t) = 2000*t
fun(t) = 2000*t
wav = chirp(2.0, 16000.0, fun)
wavwrite(wav, "./doc/0_4000hz_linear.wav", Fs=fs, nbits=32)
更多
请访问仓库 ChirpSignal