Godard algorithm in presence of Doppler

Hi All

I have implemented Godard method to estimate symbol phase and frequency
offset. lower and upper bands of Nyquist shaped spectrum are used to
extract phase and frequency information from the received signal. 

Performance in presence of Multipath and Doppler:

In presence of Doppler(5-10Hz) on one of the echoes, an amplitude
modulation is observed on symbol timing feedback, which creates problem to 
achieve required SNR. I have following questions regarding this
implementation,


1. Godard algorithm is independent of carrier phase but why Doppler phase
is effecting symbol phase/frequency estimation?

2. How to minimize/remove amplitude modulation(I have tried reducing loop
filter bandwidth of the PLL)