Siemens Aktiengesellschaft

Siemens-albis, Ag

Helmut Heinz

Michael Faerber

Holger Kunze

Meik Kottkamp

Franz Schreib

Bruno Fognini

J&ouml;rg Monschau

A method for functional testing of a transmission and reception path includes transmitting a first signal at a first transmission power level to a radio station and determining a first reception strength, with a base station. A first difference value is subsequently calculated. The radio station transmits a second signal at a second transmission power level to the base station, determines a second reception strength, and calculates a second difference value. Any difference between the difference values is then compared with a threshold value, and a function of a transmission and reception path is derived from the comparison. A base station of a radio communications system is also provided.

Method and base station for functional testing of a transmission and reception path

A method and circuit for preamplifying reception signals for a radio station. A first preamplifier is connected between an antenna unit and to the radio station. A second preamplifier is provided in the radio station, the second preamplifier being bridged by a bridge line. A switch can selectively switch the radio signals through either the second preamplier or the bridge line, under control of a controller.

Radio station preamplifier circuit with interior and exterior preamplifiers

A frequency synthesizing device comprises two reference frequency generators RG1 and RG2, an offset stage OS and a phase-locked loop PLL. In the phase-locked loop, which operates as a tracking filter, the output frequency fs.sub.A is generated by the addition of the frequencies f.sub.RG1 and f.sub.OS. The output frequency fs.sub.A has a very high spectral purity, since all interfering spurious signals are blocked by the tracking filter. By a proper selection of the reference frequencies f.sub.RG1, f.sub.RG2 and f.sub.OR, it is ensured that all interfering spurious signals lie outside the bandwidth B.sub.TF of the tracking filter and are accordingly blocked. As a result, it is not necessary to filter the signals S.sub.RG1, S.sub.RG2 and S.sub.OS.

Frequency synthesizing device

Growing community of inventors

Windach, Germany

Helmut Heinz