| abstract |
A wireless digital communication device having a pulse shaping network for pulse shaping digital signals before modulation. The pulse shaping network comprises a shift register to which data to be modulated are fed. Outputs of the shift register are connected to control inputs of switched weighted current sources. The switched weighted current sources are summed over an output resistor. An adjustment voltage for adjusting the magnitude of the shaped data is fed to one input of a differential amplifier, a reference resistor being coupled to another input of the amplifier, and to a reference current source which is mirrored into the switched weighted current sources. Thus, an accurate and easily adjustable pulse shaping network is obtained. |