The difference in performance between the Simulink Phase/Frequency Offset block and a simple mixer (signal*exp(1j*2π/N*k*n)) is likely due to their design and implementation.
The Phase/Frequency Offset block is optimized for use in communication systems, providing stable and precise offset adjustments for phase and frequency of the signal. It internally manages sample rates, scaling, and signal characteristics, ensuring consistent performance across simulations.
A simple mixer directly applies a frequency shift by multiplying the signal with a complex exponential. It is typically used in signal modulation/demodulation or bother baseband processing tasks. While straightforward, its performance can vary depending on parameter configuration and signal properties.
Here are some key differences:
- The Simulink block may trade off a small amount of speed for better precision and user convenience.
- The block uses advanced algorithms to minimize numerical errors, especially in long simulations, which can be challenging to achieve with a manually coded mixer.
- It handles sample rate mismatches and signal compatibility internally, reducing the chance of misconfiguration, whereas a simple mixer requires manual adjustments to ensure compatibility.
- The block abstracts complexities, making it easier to use without fine-tuning parameters manually, whereas a simple mixer requires careful configuration to perform optimally.
For more details on the Phase/Frequency Offset block, refer to the following documentation link:
I hope this helps.
