and wherein the processing arrangement is arranged to apply an harmonic analysis to signals corresponding to at least one of the pressure and the acceleration, the harmonic analysis being arranged to identify {HEAD ~ harmonic components} in respect of angular frequency corresponding to a temporal rate of change of the angular orientation of {TAIL ~ the at least one wheel} 
and wherein the processing arrangement is arranged to apply an harmonic analysis to signals corresponding to at least one of the pressure and the acceleration , the harmonic analysis being arranged to identify { HEAD ~ harmonic components } in respect of angular frequency corresponding to a temporal rate of change of the angular orientation of { TAIL ~ the at least one wheel }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL