Pulse position modulation symbols sphere decoding method for maximum likehood receiver, involves updating quadratic radius of sphere and nearest point, when contributions sum is less than radius

摘要

The method involves carrying out equalization of received signal of Zero-Forcing Decision Feedback Equalizer (ZF-DFE) in a current layer to count pulse position modulation (PPM) symbols is estimated in previous layers. The symbols are selected to form week contribution. The week contribution and the contribution obtained by the previous layer are added to obtain sum of contributions. The equalization, selection and adding contribution are repeated till reaching a lowest layer. Quadratic radius of a sphere and a nearest point are updated, when the contributions sum is less than the radius. An independent claim is also included for a maximum-likelihood (ML) receiver for receiving pulse position modulation (PPM) symbols of a pulse type ultra wide band multiple-input and multiple-output (MIMO) system.