发明名称 |
Blind Mechanism for the Joint Estimation of Frequency Offset and Phase Offset for QAM Modulated Signals |
摘要 |
A mechanism for jointly correcting carrier phase and carrier frequency errors in a demodulated signal. A computer system may receive samples of a baseband input signal (resulting from QAM demodulation). The computer system may compute values of a cost function J over a grid in a 2D angle-frequency space. A cost function value J(θ,ω) is computed for each point (θ,ω) in the grid by (a) applying a phase adjustment of angleθand a frequency adjustment of frequencyωto the input signal; (b) performing one or more iterations of the K-means algorithm on the samples of the adjusted signal; (c) generated a sum on each K-means cluster; and (d) adding the sums. The point (θe,ωe) in the 2D angle-frequency space that minimizes the cost function J serves an estimate for the carrier phase error and carrier frequency error. The estimated errors may be used to correct the input signal.
|
申请公布号 |
US2011182387(A1) |
申请公布日期 |
2011.07.28 |
申请号 |
US20100694388 |
申请日期 |
2010.01.27 |
申请人 |
AHMED I ZAKIR;BHARADWAJ KRISHNA;YAJNANARAYANA VIJAYA |
发明人 |
AHMED I ZAKIR;BHARADWAJ KRISHNA;YAJNANARAYANA VIJAYA |
分类号 |
H04L27/14;H04L27/38 |
主分类号 |
H04L27/14 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|