EE 445S Real-Time Digital Signal Processing Lab Fall 2013 Lab #5.2 PAM Symbol Clock Recovery Chao Jia

Outline Recap: The Symbol Clock Recovery Block in the Receiver. Symbol Clock Recovery: Step by Step.

Symbol Clock Recovery: Recap In PAM systems, the receiver has no perfect knowledge of the transmitter’s symbol clock frequency The symbol clock recovery module is used to recover the transmitter’s symbol frequency.

Symbol Clock Recovery: Prefiltering Recall from last time: If we define g(t) to be equal to: Then the output of the receive filter is:

Symbol Clock Recovery: Prefiltering & Squaring Under the assumption of no additive noise in the channel:

Symbol Clock Recovery: Squaring Fourier Series Expansion

Symbol Clock Recovery: Bandpass and PLL : a bandpass filter centered half of the symbol rate. Then except for k = -1,0,1 : a bandpass filter centered at the symbol rate. Then except for k=-1,1 is a sinusoid signal at the symbol clock frequency. is a sinusoid with a slowly varying amplitude and phase Design the two filters using fdatool and implement them using code in lab3 (biquads)