Apparatus and method for measuring signal quality of a wireless communications link,申请号US20020322130-传众专利搜索

Apparatus and method for measuring signal quality of a wireless communications link

申请公布号：US7016651(B1)

申请号：US20020322130

申请日期：2002.12.17

申请公布日期：2006.03.21

申请人：

MARVELL INTERNATIONAL LTD.

发明人：NARASIMHAN RAVI

分类号：H04L1/02

主分类号：H04L1/02

摘要：Techniques for measuring signal quality in a communications link supporting OFDM symbol transfer across plural sub-carriers are disclosed. These techniques employ a link interface receiving OFDM symbol(s) from the link, and a signal-to-noise ratio (SNR) estimation unit generating an estimate of a geometric SNR (SNRgeo) for the received symbols based on an average of the logarithmic difference between soft decision and hard decisions for the received symbol. SNRgeo here defines a scalar measure of the link signal quality, which results in a computationally efficient yet accurate link signal quality assessment, and thereby permit selective link characteristic alteration. Only sub-carrier subsets need be used to derive a relatively accurate SNRgeo estimate. Sharing calculation resources between SNR estimation and soft decision units further reduce implementation complexity. Hard decision generation may use a relatively quick slicer or more accurate viterbi decoder/OFDM re-coder combination, as design goals dictate.