Comparison of Two Different Upsampling Methods Used for Interpolation in Symbol Timing Recovery in Digital Receivers
Cheng Tao, Liu Liu · International Conference on Advanced Communication Technology · 2007
The digital method for symbol timing recovery has been used for several years and many scholars have proposed a great deal of methods for it. This paper describes the fundamentals of interpolation for timing recovery, and compares the differences between the two upsampling: zero-insertion expander and zero-order-hold expander used before the symbol timing interpolation. It is shown that, through simulation, zero-order-hold expander performs better than zero-insertion expander in the frequency domain, and has better attenuation for signal images caused by upsampling using the same low band filter.