Given unlimited bit depth and sample rate, an IQ capture can perfectly recreate an RF signal from any period in time. In the real world, however, more bit depth and more samples come at a cost of more bits, and these bits can quickly consume gigabytes of storage and tens of gigabits per second of streaming bandwidth. Every capture contains noise. At some point, more bits only serve to better quantify the noise and no longer provide any additional insight into the signal.
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