Global convergence of a Single-Axis Constant Modulus algorithm

We propose a modification to the Constant Modulus Criterion for real valued sources processed with a complex valued receiver. Our modification is called Single-Axis Constant Modulus Criterion (SA-CM) because it operates solely on the real component of the complex equalizer output. We show that under idealized conditions, a finite length, baud-spaced, complex valued equalizer minimizing the SA-CM criterion admits only desirable global minima settings that are ISI-free. A single-axis receiver architecture is compared to other receiver architectures for real valued sources and staggered modulation schemes. Simulation examples using vestigal sideband (VSB) signaling verify our methods.