diff --git a/src/data/Signalpath.py b/src/data/Signalpath.py
index aeab33b..320ab58 100644
--- a/src/data/Signalpath.py
+++ b/src/data/Signalpath.py
@@ -1,9 +1,37 @@
 import numpy as N
+
 class Signalpath:
     def phase(self, degrees):
-        tmp = self.y[0] + 1j*self.y[1]
-        tmp *= N.exp(1j*degrees*N.pi/180)
-        self.y[0] = tmp.real
-        self.y[1] = tmp.imag
-        del tmp
+        """
+        rotate signal by **degrees** for phase cycling, etc.
+
+        :param degrees: rotate signal by this value
+        :return:
+        """
+        if self.get_number_of_channels() != 2:
+            raise Exception("rotation defined only for 2 channels")
+        # simple case 0, 90, 180, 270 degree
+        reduced_angle = divmod(degrees, 90)
+        if abs(reduced_angle[1]) < 1e-6:
+            reduced_angle = reduced_angle[0] % 4
+            if reduced_angle == 0:
+                return
+
+            elif reduced_angle == 1:
+                self.y[1] *= -1
+                self.y = [self.y[1], self.y[0]]
+
+            elif reduced_angle == 2:
+                self.y[0] *= -1
+                self.y[1] *= -1
+
+            elif reduced_angle == 3:
+                self.y[0] *= -1
+                self.y = [self.y[1], self.y[0]]
+        else:
+            sin_angle = N.sin(degrees / 180.0 * N.pi)
+            cos_angle = N.cos(degrees / 180.0 * N.pi)
+            self.y = [cos_angle * self.y[0] - sin_angle * self.y[1],
+                      sin_angle * self.y[0] + cos_angle * self.y[1]]
+
         return self