3.1.1. Time Difference of Arrival

The time difference *τ* is expressed as:

$$TDOA\_q = \left\lfloor \frac{||\mathbf{x}\_i - \mathbf{s}\_{q,1}|| - ||\mathbf{x}\_i - \mathbf{s}\_{q,2}||}{v} \right\rfloor,\tag{14}$$

where both x*<sup>i</sup>* and *sq*,*<sup>j</sup>* are in Cartesian coordinates, · is the Euclidean-norm and *v* is the velocity of sound.
