Abstract: The transmitter is built according to the LINC principle and has two parallel signal branches, each of which includes an amplifier (V1, V2) and a phase modulator (PM1, PM2). A dividing network (WE) is provided which divides the received signal (DI) between both signal branches and a combining device (KB) which adds the output signals (S11, S22) of both signal branches to form a sum signal (SS). In order to control the phase error in both signal branches the dividing network (WE) is designed so that the assignment of the received signal components (S1, S2) in both signal branches is periodically exchanged at a predetermined cycle frequency (fc). The amplitude modulation of the sum signal (SS) generated by the cyclic exchange of the input signal components (S1,S2) is detected and the phase depending on it in at least one of the signal branches is changed so that amplitude modulation is minimized.

Abstract: A method of generating a composite signal in the form of a QPSK signal on which an additional carrier signal is superposed, wherein a carrier signal is conducted through two series connected, switchable phase shifters. One of the phase shifters is controlled by one of two data signals. Both data signals are logically linked with one another by a logic circuit, and the resulting linkage signal used to control the other phase shifter. The phase states into which each phase shifter can be switched are selected and the linkage signal formed from the data signals such that, with the available values of the data signals, the carrier signal passing through the phase shifters is brought into the phase positions that should exist with the additional carrier signal superposed.

Abstract: An arrangement for coupling waveguide modes between two waveguides via a semiconductor element. The two waveguides each have a short-circuiting end wall and a common side wall constituting a common partition wall between the waveguides so that the two waveguides extend parallel to, and overlap one another at least over a partial length where they are separated from one another by the common side wall. The common partition wall is provided with a coupling aperture and the semiconductor element is inserted into the coupling aperture between the two waveguides and is in ground contact with the common partition wall. The semiconductor element has two connectng arms, one connecting arm extending as a coupling probe into one of the waveguides and the other connecting arm extending as a coupling probe into the other waveguide.

Abstract: A waveguide-microstrip transition arrangement including, a waveguide section and a microstrip portion, for coupling waveguide modes between the waveguide section and the microstrip portion. The waveguide section has waveguide walls defining waveguide wall surfaces including a short-circuited end wall surface and side wall surfaces. A channel passes through one of the side walls and presents an opening at the associated wall surface. The microstrip portion includes a substrate having opposite sides with a ground plane disposed on one side of the substrate and a microstrip conductor disposed on the other side of the substrate. The substrate passes through the waveguide section, entering the waveguide section at a location where the wall currents of the waveguide section flowing transversely to the substrate are at a miniumum. A portion of the microstrip conductor is disposed on the substrate to pass through the channel into the waveguide section free of contact with the waveguide walls.

Abstract: In a demodulator for demodulating a phase difference modulated microwave frequency signal, which demodulator includes a time delay element, a phase shifting unit connected in series with the time delay element, the series arrangement of the time delay element and phase shifting unit being connected to conduct the phase difference modulated signal, and two phase detectors each having one input connected to directly receive the phase difference modulated signal and its other input connected to receive that signal after it has passed through the time delay element and phase shifting unit, each phase detector includes two high sensitivity diodes having their outputs isolated from one another and two separate operating resistors each connected to only a respective one of the diodes, and the time delay element is constituted by a low loss waveguide filter.