EURASIP Journal on Applied Signal Processing
Volume 2004 (2004), Issue 8, Pages 1059-1077
doi:10.1155/S1110865704311133
Abstract
We address the problem of estimating the speed of a
road vehicle from its acoustic signature, recorded by a pair of
omnidirectional microphones located next to the road. This choice
of sensors is motivated by their nonintrusive nature as well as
low installation and maintenance costs. A novel estimation
technique is proposed, which is based on the maximum likelihood
principle. It directly estimates car speed without any
assumptions on the acoustic signal emitted by the vehicle. This
has the advantages of bypassing troublesome intermediate delay
estimation steps as well as eliminating the need for an accurate
yet general enough acoustic traffic model. An analysis of the
estimate for narrowband and broadband sources is provided and
verified with computer simulations. The estimation algorithm uses
a bank of modified crosscorrelators and therefore it is well
suited to DSP implementation, performing well with preliminary
field data.