Equalizer performance enhancements for broadband wireless applications

USRE42021E1 · kind E1 · reissue

Inventors

• Stephen C. Pollmann · Santee, US
• Eli Arviv · Lod, IL
• Jacques Behar · Jerusalem, IL
• Timothy Gallagher · Encinitas, US
• David Gazelle · Givat Shmuel, IL
• Frederick W. Price · Carlsbad, US

Key dates

• Filing date: Jul 20, 2005
• Grant date: Jan 4, 2011
• Expiry date: Jul 20, 2025

Classification

• Technology area (CPC —): General

Abstract

A system and method for enhancing the performance of an equalizer in a modem. Multiple techniques are disclosed which improve the modem performance. A first technique uses stored parameters for each burst from each remote site to demodulate a received data stream. A second technique compensates for the gain droop caused by storing parameters across each burst. A third technique minimizes errors caused by adapting the equalizer coefficients for each data burst by analyzing the SN ratio and error rate of the received burst. A fourth technique improves the convergence of the equalizer by using a two-part preamble, whereby both parts are transmitted using different modulation techniques. A fifth technique is provided which performs a soft reset of the modem without performing a complete reset of the modem. A sixth technique determines a modem adaptation factor based on the expected modulation type of an incoming burst transmission. A seventh technique calculates a phase correction value for the stored tap values and applies the value to the incoming signal.