Te Gradient-Lattice Per Tone Eualizer for wireless LAN

The cyclic prefix orthogonal frequency division modulation (CP-OFDM) is a widely accepted transmission method for wired or wireless communications. In order that the CP-OFDM works correctly, it should be assumed that the CP is longer than the channel impulse response (CIR); however, the CIR length is time-varying, which may cause the assumption to fail. To keep this assumption, the time-domain equalizers (TEQs) or per-tone equalizers (PTEQs) were proposed for the digital-subscriber-line (DSL) channels. This paper first investigates the use of the several PTEQ algorithms for the wireless LAN channel, and then applies another PTEQ algorithm, the gradient-lattice PTEQ (GL-PTEQ), to this channel. Its fast convergence and low computational complexity makes the GL-PTEQ suitable for the equalization of the wireless LAN channel