Improving Dynamic Range

Figure 6-2 shows the dynamic range for one resolution bandwidth. We
certainly can improve dynamic range by narrowing the resolution bandwidth,
but there is not a one-to-one correspondence between the lowered noise
floor and the improvement in dynamic range. For second-order distortion,
the improvement is one half the change in the noise floor; for third-order
distortion, two-thirds the change in the noise floor. See Figure 6-3.

Figure 6-3. Reducing resolution bandwidth improves dynamic range