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The fundamental limit for optical detection is . In many real-world scenarios, the noise from the environment (the 300K background radiating onto your detector) is higher than the noise from your amplifier or the signal itself. radiometry and the detection of optical radiation boyd pdf
Before you click on a suspicious "free PDF" link, check your institution’s online library portal. The legal, high-quality scan is likely just a login away. Respect the copyright, and appreciate the genius of Robert W. Boyd. References: The fundamental limit for optical detection is