Quasi-coherent Delay-locked Loops for Fading Channels
نویسنده
چکیده
In a coherent RAKE receiver the complex channel coee-cient estimate can be used to attain the phase coherency in DLL and the eeect of data modulation can be removed via decision feedback. The resulting algorithms are called quasi-coherent delay-locked loops (QCDLL). The performance of four variations for QCDLLs based on lead-lag phase-locked loops has been analyzed by computer simulations. All the loops performed satisfactorily in a fading channel, but the quasi-coherent sample-correlate-choose-largest (QCSCCL) loop had 5-6 dB better performance than the other schemes.
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