Pulse or digital communications – Receivers – Interference or noise reduction
Reexamination Certificate
2006-01-24
2006-01-24
Burd, Kevin (Department: 2631)
Pulse or digital communications
Receivers
Interference or noise reduction
Reexamination Certificate
active
06990158
ABSTRACT:
An equalizer operates on chip or sub-chip resolution input samples of a received spread-spectrum multipath signal to remove interference from one or more secondary propagation path signals within the multipath signal. The equalizer may be configured for cancellation of secondary signals arriving before and after a main propagation path signal. The length of sample delay buffers and the input sample rate determine the maximum secondary signal delay accommodated by the equalizer. The equalizer makes a hard-decision about the phase value of each input sample and buffers these hard-decision values for use in secondary signal cancellation. The hard-decision values are used to rotate the phase of corresponding path coefficients. These adjusted values are fed back for subtraction from input samples for post-cursor cancellation, and fed forward for subtraction from delayed input samples for pre-cursor cancellation.
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King Eric J.
Shan Peijun
Burd Kevin
RF Micro Devices, Inc.
Withrow & Terranova , PLLC
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