At first it might seem that complex sinusoids complicate your study of signal processing. On the contrary, complex sinusoids simplify signal processing analysis and computation. This lesson will provide you with understanding of complex sinusoids that is essential to work and study in the field of signal processing.
The real and imaginary parts of a complex sinusoid are sinusoids of the same frequency. Importantly, the types of systems often used to manipulate signals act in a very special way with complex sinusoidal input signals. This property is stated here and explored more fully in later lessons. Complex sinusoids also simplify the algebra and computation involved in signal processing. Finally, this lesson addresses the meaning and role of “negative” frequency in signal representation.