Patent ID: 6956371

Claim:
A method for nuclear magnetic resonance (NMR) measurement of petrophysical properties of an earth formation, comprising: providing at least one first plurality of NMR pulses having at least one excitation and at least one refocusing pulse followed by a de-phasing delay and further followed by at least one test excitation pulse and at least a test refocusing pulse; and receiving at least one first signal in response to the at least one first plurality of NMR pulses; and combining the received at least one first signal with a second signal to reduce ringing error; wherein a second plurality of NMR pulses is generated at a second frequency, F 2 , which is different from a frequency, F 1 , of the at least one first plurality of NMR pulses, to generate the second signal, and wherein the difference between the first and second frequencies is given by  F 1 - F 2  = ( n + 1 2 ) ⁢ 1 2 ⁢ τ , wherein n is an integer, and τ is an inter echo spacing.