Coordinate converter for changing polar vector variable into Cartesian vector variables

DETAILED DESCRIPTION According to the invention, this problem is solved by means of a first and a second multiplier in conjunction with an adder and a subtractor, the first variable being fed to the first input of the first multiplier and the output variable of the adder to the second input of the first multiplier.
The adder, in turn, is addressed by the second variable and the output variable of the subtraction member.
The output variable of the first multiplier is taken off as the fourth variable and is also fed to one input of the second multiplier.
The other input of the second multiplier is addressed by the first variable.
The second variable is fed to the adding input of the subtraction member and the output variable of the second multiplier is fed to the subtracting input of the subtraction number.
The output variable of the subtraction member is taken off as the third variable.
The coordinate converter of the present invention constitues a basic unit for forming Cartesian coordinates from the polar coordinates of a vector.
The given polar coordinates are the magnitude and the tangent of one-half of the angle which can be measured between a coordinate axis and the vector, i.
e.
, a quantity similar to an angle.
With such a so-called PT/K converter (PT for "polar-tangent", K for "Cartesian"), which is of very simple design, certain problems can be satisfactorily solved.
The operating range for angle being between +90.
degree.
and -90.
degree.
, however, rotating vectors can not be processed with a coordinate converter in this form.
To expand the operating range, the output variable of the adder is fed to the second input of the first multiplier via a first proportional member, and the output variable of the second multiplier is fed to the subtraction member via a second proportional member.
The factors of the two proportional members determine the size of the effective angle range.
Frequently, a variable which is not proportional to the tangent of one-half the angle but is directly proportional to this angle is available as the first variable