Communications Blockset

Baseband Modulated Signals Defined

A baseband representation of a modulated signal is often more convenient for simulation than the passband representation is. Suppose the modulated signal has the waveform

where Y₁ and Y₂ are amplitude terms, f_c is the carrier frequency and is the carrier signal's initial phase. A baseband simulation recognizes that this equals

and models only the part inside the curly brackets. Here j is the square root of -1. The complex vector y is a sampling of the complex signal (Y₁(t) + jY₂(t)) exp(j).

Analog Modulation Features of the Blockset

Representing Signals for Analog Modulation