Telefonaktiebolaget Lm Ericsson (publ)

Gerlach Spee

Li Wang

Youping Su

Mats Klingberg

Gunnar Persson

Björk Vimar

There is disclosed mechanisms for calibrating a homodyne receiver in a signal distribution network for time division duplex; a corresponding method is performed by a baseband calibration module. The method comprises acquiring a transmission signal being input to a homodyne transmitter of the signal distribution network; acquiring, from a heterodyne transmitter observation receiver of the signal distribution network, a first received version of the transmission signal; acquiring, from a homodyne receiver of the signal distribution network, a second received version of the transmission signal; and, calibrating the homodyne receiver using a comparison of the first received version of the transmission signal and the second received version of the transmission signal, using the first received version of the transmission signal as a reference signal, and using the transmission signal as a calibration signal.

Homodyne receiver calibration

The present invention relates to an analog predistorter () having a tunable amplitude () and/or phase () expansion. The predistorter () includes a coupler () having an input port (), an output port (), a first () and a second () coupled port separated by 90 degrees. A first compensation circuit (A) is connected to the first coupled port () and comprises a first combination (A) of linear (A) and nonlinear (A) circuit elements and a first impedance adjusting unit (A) for adjusting the impedance seen by the nonlinear circuit element (A). A second compensation circuit (B) is connected to the second coupled port () and comprises a second combination (B) of linear (B) and nonlinear (B) circuit elements a second impedance adjusting unit (B) for adjusting the impedance seen by said nonlinear circuit element (B). By adjusting the impedances seen by the nonlinear circuit elements (IA,B) the amplitude () and/or phase () expansion of the predisorter () are tuned.

Growing community of inventors

Ösmo, Sweden

Gerlach Spee