Method of data modulation adapted to selected modulation rotational angle

Abstract

In a method, modulator, transmitter and receiver, the modulator of data signals to be transmitted simultaneously to at least two receiving mobile stations in the same transmission time slot is adapted to select rotational angle of a QPSK transmission modulation, such as a hybrid a-QPSK modulation used to modulate the data signals to the at least two mobile stations in response to the capabilities of the mobile stations that share the same transmission slot.

1 - 21 . (canceled) 
     
     
         22 . A method, performed in a mobile station operative in a wireless communication system, comprising:
 receiving a modulated data signal, the modulated data signal comprising modulated data for at least two mobile stations transmitted at the same frequency and in the same time slot; and   blindly detecting a rotational angle of the modulated data signal.   
     
     
         23 . The method of  claim 22 , further comprising de-rotating the received signal based on the blind detection of the rotation angle. 
     
     
         24 . A method, performed in a mobile station operative in a wireless communication system, comprising:
 receiving a modulated data signal, the modulated data signal comprising modulated data for at least two mobile stations transmitted at the same frequency and in the same time slot; and   receiving as signaled information a rotational angle of the modulated data signal.   
     
     
         25 . The method of  claim 24 , further comprising de-rotating the received signal based on the signaled rotation angle. 
     
     
         26 . A mobile station operative in a wireless communication system, comprising:
 a receiver adapted to receive a modulated data signal where the modulated data signal comprises modulated data for at least two mobile stations transmitted at the same frequency and in the same time slot; and   a blind detector adapted to blindly detect a rotational angle of the modulated data signal.   
     
     
         27 . The mobile station of  claim 26 , further comprising a de-rotator adapted to perform a de-rotation of the received signal based on the blindly detected rotational angle. 
     
     
         28 . A mobile station operative in a wireless communication system, comprising:
 a receiver adapted to receive a modulated data signal where the modulated data signal comprises modulated data for at least two mobile stations transmitted at the same frequency and in the same time slot; and   wherein the receiver is further adapted to receive a rotational angle of the modulated data signal as signaled information.   
     
     
         29 . The mobile station of  claim 28 , further comprising a de-rotator adapted to perform a de-rotation of the received signal based on the signaled rotational angle.