FPGA starter
DSPs and FPGAs are utterly different devices, but they can both do digital signal processing.
A DSP is a microprocessor optimized for efficient multiply-accumulate loops. You write a program that executes your signal processing (or other) algorithm.
An FPGA is like a box full of unconnected digital logic chips. You connect the logic to implement your signal processing (or other) stages. Modern FPGAs include registers, multipliers, fast arithmetic, and ROM/RAM blocks that help you build signal processing stages.
I've used DSP chips for many years. About five years ago, I stopped using them because modern FPGAs are so much faster and less expensive.
A good way to learn FPGA signal processing is to buy a low-cost FPGA development kit, and read app notes like these:
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