In-phase quadrature modulation, or IQ modulation, is the dominant modulation scheme in communication applications. It is popular because of its efficient use of bandwidth, which continues to be a challenge in our data-hungry world. Testing with simulated IQ signals is critical because designers face a continual bandwidth crunch in a spectrum filled with interference.
For example, designers need to test their designs’ limits to ensure real-world performance. To do this, they must first generate an ideal signal using a function generator to test the design’s ideal performance. Therefore, they must generate a high-quality, known-good signal.
Function generators play a crucial role in simulating nonideal IQ signals. By adjusting the gain balance between the two channels and the amplitude offset for each channel, you can create nonideal signals. You can even perform skew adjustment to shift either the I or Q baseband signal in time with picoseconds of resolution. Some function generators allow you to perform advanced modulation to add noise, random jitter, or deterministic jitter to the signal, showcasing their versatility in testing.