Introduction

This short tutorial will show you how to make a sine wave that is calibrate to the sample rate you set.

Details

A sinusoid, meaning a sine or cosine wave, is a very useful waveform. It's the primary waveform used to create all major wireless signals, including cellular, 802.11, Bluetooth, FM broadcast, television, you name it.

This makes it useful to know how to create a sine wave that is calibrated to the particular sample rate you set.

The function is as follows:

where: * freq = the frequency of the desired sinewave, in Hz. * sample rate = the sample rate of the system

Let's make one. We'll use the code below:

t=1:1000; freq=20; % This is the frequency, in Hz, of the sinewave. sampleRate=10000; % This is the sample rate of the system, in Hz. x=sin(2*pi*t*freq/sampleRate); time=t/sampleRate; % This creates the time line, in seconds, for the display. plot(time,x) xlim([0, (1/freq)]) % This adjusts the time line of the display so that only one cycle is made. print('sinewave.png') % This prints the sine wave to a file so that you can import it into a document, if you desire.

This results in the following sinewave:

Note that the time on the horizontal axis is calibrated in seconds. The sinewave we made was a 20 Hz sinewave. This means it completes one cycle in 1/20=0.05 seconds. This is shown in the display.