A method of remotely measuring rotation of a target illuminated with incident coherent light, comprising: measuring, at a detector having a field of view divided into at least four spatially distinct light sensing segments (300A, 300B, 300C, 300D), coherent light reflected from a target incident upon the detector field of view; outputting, by the detector, a plurality of signals (A, B, C, D) to one or more processors, each signal (A, B, C, D) representing a Doppler spread of the reflected light received at a respective detector segment (300A, 300B. 300C, 300D); and determining, by the one or more processors: a first Doppler spread for reflected light received at a first half of the detector, the first Doppler spread including a first Doppler shift; a second Doppler spread for reflected light received at second half of the detector corresponding to the first half, the second Doppler spread including a second Doppler shift, wherein the first and second halves of the detector are separated along a first detector axis of division; and a first Doppler shift difference between the first and second Doppler shifts; further determining, by the one or more processors: a third Doppler spread for reflected light received at a third half of the detector, the third Doppler spread including a third Doppler shift; and a fourth Doppler spread for reflected light received at a fourth half of the detector corresponding to the third half, the fourth Doppler spread including a fourth Doppler shift; and a second Doppler shift difference between the third and fourth Doppler shifts; wherein the third and fourth halves of the detector are separated along a second detector axis of division orthogonal to the first detector axis of division; and identifying, by the one or more processors, a rotation axis of the target, the rotation axis aligned with a vector given by the sum of: a first vector aligned with the first detector axis of division and having a magnitude given by the first Doppler shift difference; and a second vector aligned with the second detector axis of division and having a magnitude given by the second Doppler shift difference. measuring, at a detector having a field of view divided into at least four spatially distinct light sensing segments (300A, 300B, 300C, 300D), coherent light reflected from a target incident upon the detector field of view; outputting, by the detector, a plurality of signals (A, B, C, D) to one or more processors, each signal (A, B, C, D) representing a Doppler spread of the reflected light received at a respective detector segment (300A, 300B. 300C, 300D); and determining, by the one or more processors: a first Doppler spread for reflected light received at a first half of the detector, the first Doppler spread including a first Doppler shift; a second Doppler spread for reflected light received at second half of the detector corresponding to the first half, the second Doppler spread including a second Doppler shift, wherein the first and second halves of the detector are separated along a first detector axis of division; and a first Doppler shift difference between the first and second Doppler shifts; a first Doppler spread for reflected light received at a first half of the detector, the first Doppler spread including a first Doppler shift; a second Doppler spread for reflected light received at second half of the detector corresponding to the first half, the second Doppler spread including a second Doppler shift, wherein the first and second halves of the detector are separated along a first detector axis of division; and a first Doppler shift difference between the first and second Doppler shifts; further determining, by the one or more processors: a third Doppler spread for reflected light received at a third half of the detector, the third Doppler spread including a third Doppler shift; and a fourth Doppler spread for reflected light received at a fourth half of the detector corresponding to the third half, the fourth Doppler spread including a fourth Doppler shift; and a second Doppler shift difference between the third and fourth Doppler shifts; wherein the third and fourth halves of the detector are separated along a second detector axis of division orthogonal to the first detector axis of division; and a third Doppler spread for reflected light received at a third half of the detector, the third Doppler spread including a third Doppler shift; and a fourth Doppler spread for reflected light received at a fourth half of the detector corresponding to the third half, the fourth Doppler spread including a fourth Doppler shift; and a second Doppler shift difference between the third and fourth Doppler shifts; wherein the third and fourth halves of the detector are separated along a second detector axis of division orthogonal to the first detector axis of division; and identifying, by the one or more processors, a rotation axis of the target, the rotation axis aligned with a vector given by the sum of: a first vector aligned with the first detector axis of division and having a magnitude given by the first Doppler shift difference; and a second vector aligned with the second detector axis of division and having a magnitude given by the second Doppler shift difference. a first vector aligned with the first detector axis of division and having a magnitude given by the first Doppler shift difference; and a second vector aligned with the second detector axis of division and having a magnitude given by the second Doppler shift difference.