  Electron spin resonance (ESR) pulsed dipolar spectroscopy (PDS) is used in
protein 3D structure determination. However, the accuracy of the signal
analysis depends heavily on the background correction process. In this work, we
derive the functional forms of double quantum coherence (DQC) ESR signal in
typical frozen samples of micro-molar concentration, quantifying both the
intramolecular and the background contributions.
