A non-transitory computer readable medium having processor readable petrophysical properties analyzing program code embodied on the computer readable medium, the processor readable program code for programming one or more processors to perform operations for analyzing properties of rock in a formation in real-time during drilling, the processor readable program code comprising a set of instructions that when executed by the one or more processors , cause the one or more processors to perform the operations being characterized by : sending sampling commands to a surface data acquisition unit in communication with a downhole data interface through a surface data interface and a communication medium extending between the surface data interface and the downhole data interface , the raw acoustic sensor data representing an acoustic signal generated real-time as a result of rotational contact of a drill bit with rock during drilling, the downhole data interface operably coupled to a plurality of acoustic sensors carried by a downhole sensor assembly , receiving digitized raw acoustic sensor data from the surface data acquisition unit ; transforming the raw acoustic sensor data into the frequency domain, filtering the transformed data, and performing the following processing operations: deriving a plurality of acoustic characteristics from the filtered data , the plurality of acoustic characteristics including mean frequency and normalized deviation of frequency, and deriving petrophysical properties from the filtered data utilizing a petrophysical properties evaluation algorithm employed to predict one or more petrophysical properties of rock undergoing drilling. sending sampling commands to a surface data acquisition unit in communication with a downhole data interface through a surface data interface and a communication medium extending between the surface data interface and the downhole data interface , the raw acoustic sensor data representing an acoustic signal generated real-time as a result of rotational contact of a drill bit with rock during drilling, the downhole data interface operably coupled to a plurality of acoustic sensors carried by a downhole sensor assembly , receiving digitized raw acoustic sensor data from the surface data acquisition unit ; transforming the raw acoustic sensor data into the frequency domain, filtering the transformed data, and performing the following processing operations: deriving a plurality of acoustic characteristics from the filtered data , the plurality of acoustic characteristics including mean frequency and normalized deviation of frequency, and deriving petrophysical properties from the filtered data utilizing a petrophysical properties evaluation algorithm employed to predict one or more petrophysical properties of rock undergoing drilling. deriving a plurality of acoustic characteristics from the filtered data , the plurality of acoustic characteristics including mean frequency and normalized deviation of frequency, and deriving petrophysical properties from the filtered data utilizing a petrophysical properties evaluation algorithm employed to predict one or more petrophysical properties of rock undergoing drilling. <EOS>