Resolve cross-modulation in multi-carrier A-RoF links

Resolve the cross-modulation products between different frequency bands in analog radio-over-fiber links operating under multi-carrier and multi-band multiplexing conditions.

Background

Analog radio-over-fiber links are subject to nonlinear distortion arising from laser relative-intensity noise, Mach–Zehnder-modulator nonlinearity, and fiber-dispersion-induced power fading. These impairments become more difficult to control when multiple carriers and frequency bands share the same optical link.

The paper notes that existing electrical, optical, and digital predistortion techniques improve spurious-free dynamic range, but cross-modulation products between different frequency bands remain unresolved. This issue is important because such products can fall within signal bands and degrade error-vector magnitude and overall fronthaul performance in wideband 6G deployments.