Abstract: A MIMO signal generator is adapted to generate a MIMO signal is provided. The MIMO signal generator comprises a signal generator, a signal divider and a frequency shifter. The signal generator is adapted to generate a plurality of frequency shifted partial MIMO signals within a first signal generator output signal. The frequency shifted partial MIMO signals being arranged on the frequency axis in a non-overlapping manner. The signal divider is adapted to divide the first signal generator output signal into a plurality of signal paths. The frequency shifter preferably comprises a frequency shifting device in at least one of the plurality of signal paths. The frequency shifting devices are adapted to shift the frequencies of the plurality of frequency shifted partial MIMO signals to a joint carrier frequency, resulting in a plurality of partial MIMO signals, forming the MIMO signal.

Abstract: The invention relates to a method for improving the output signal accuracy of a transmitter with a forward branch for converting an input signal into a signal for transmission. The forward branch comprises an adaptation unit (103) for applying a predistortion to the input signal and a power amplifier (106). The transmitter has a first feedback branch (110), the first feedback branch (110) generating a feedback signal from the signal for transmission, said feedback signal being fed back to the adaptation unit (103), and the predistortion applied to the input signal is determined according to the feedback signal. The method comprises the steps of: measuring the output power of said signal for transmission in a second feedback branch (201) and adjusting the predistortion according to said measurement of the output power. A transmitter and a computer program product adapted to the method are also described.

Abstract: In telecommunication devices like power amplifiers for cellular systems the amplitude of a transmission signal has to be limited to avoid signal deterioration. The improve the effciency of such amplitude limiter the present invention proposes to fed the input sample sequence to an estimation filter (56, 57) to determine the actual signal overshoot over a predefined threshold value. By this a clipping control signal to adjust the amplitude of the transmission signal accordingly can be generated with higher accuracy.