Near-Field Channel Matrix

Technical Explanation

Traditional wireless channel modeling relies on far-field planar wave approximations where channel matrices have low rank determined solely by physical scatterers. In the radiative near-field (Fresnel) zone of 6G XL-MIMO arrays, electromagnetic waves are spherical. The Near-Field Channel Matrix utilizes spherical harmonic expansions and dyadic Green's functions, mathematically revealing extra spatial degrees of freedom that allow massive spatial multiplexing even in pure line-of-sight channels.

Key Functions

• Mathematical formulation of spherical electromagnetic wave propagation in large arrays
• Revealing extra spatial degrees of freedom in pure line-of-sight wireless environments
• Calculating accurate near-field beamforming weight vectors for 3D focal spots
• Replacing flat planar wave steering vectors with spherical dyadic Green's functions
• Theoretical mathematical framework powering 6G near-field beamforming and XL-MIMO