machael
Member level 2
costas pll
Hi guys!
I'm doing a project: using a DSP to demodulate a digital packet which is modulated by BPSK. Because the phase noise is a little big, so I decide to use coherent demodulation by a digital Costas PLL.
I've found a pretty good tutorial about costas pll named<Carrier Recovery Using a Second Order Costas Loop> by google. And this article provide the method to decide the two parameters in the loop filter of a costas pll.
\[\alpha=2\zeta(\frac{2B_lT_s}{\zeta+\frac{1}{4\zeta}})\]
\[\beta=2(\frac{2B_lT_s}{\zeta+\frac{1}{4\zeta}})^2\]
in which, \[\zeta=0.707\]
However, How to decide the \[B_l\], the bandwidth of the loop filter? is it should be correlated to the bandwidth of the BPSK signal?
Thanks a lot!
Hi guys!
I'm doing a project: using a DSP to demodulate a digital packet which is modulated by BPSK. Because the phase noise is a little big, so I decide to use coherent demodulation by a digital Costas PLL.
I've found a pretty good tutorial about costas pll named<Carrier Recovery Using a Second Order Costas Loop> by google. And this article provide the method to decide the two parameters in the loop filter of a costas pll.
\[\alpha=2\zeta(\frac{2B_lT_s}{\zeta+\frac{1}{4\zeta}})\]
\[\beta=2(\frac{2B_lT_s}{\zeta+\frac{1}{4\zeta}})^2\]
in which, \[\zeta=0.707\]
However, How to decide the \[B_l\], the bandwidth of the loop filter? is it should be correlated to the bandwidth of the BPSK signal?
Thanks a lot!
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