Digital Signal Processing: Lock-In Amplifier

I need the professional skill set of an experienced freelancer in signal processing. Specifically, your proficiencies should include C and C++ programming languages as well as digital signal processing. The main thrust of this project hinges on the application of digital signal processing for a lock-in phase amplifier, IIR, and FIR filters.
Applying your expertise well will result in achieving the project's goal. A basic yet solid grasp of signal processing is important. This project indeed offers a unique opportunity to apply digital signal processing in a rewarding practical scenario. Ready to take the challenge?