semion_z
Newbie level 4

I have designed the QPSK transmitter and receiver system in Simulink based on the costas loop implementation.
The data rate is 1 MHz.
Carrier frequency is 5 MHz.
Without any frequency shift the system works well but when I introduce even a small shift, the costas loop is not able to track the signal.
Please help me to find the problem in the design (it is attached).
Thanks in advance.
The data rate is 1 MHz.
Carrier frequency is 5 MHz.
Without any frequency shift the system works well but when I introduce even a small shift, the costas loop is not able to track the signal.
Please help me to find the problem in the design (it is attached).
Thanks in advance.