Cosine Effect

Cosine Effect


The relative speed of an object as result of being measured by radar/LIDAR from an angle that is off-set by an angle from the object’s angle of approach.

The formula is as follows: Measured Speed = (Actual Speed) * (Cosine of the off-set angle)

As a result, if the off-set angle increases, the Measured Speed will decrease with respect to the Actual Speed.


cosine_effect_trafic_radar Here is an example: Actual Speed = 55mph.

  • Angle of Patrol Car = 0° Measured Speed = 55mph.
  • Angle of Patrol Car = 10° Measured Speed = 54mph.
  • Angle of Patrol Car = 20° Measured Speed = 52mph.
  • Angle of Patrol Car = 30° Measured Speed = 48mph.
  • Angle of Patrol Car = 40° Measured Speed = 42mph.