| 摘要 |
The device comprises a power divider (1') for distributing input power to several amplification routes, an amplifier set (2') containing an amplifier (22) for each route, a power combiner (5) for combining the amplified signals at the output of each route to form an output signal, and a control circuit (6) determining the number of amplified signals for combining according to the required output power. The amplifier (22) for each route comprises an integrated circuit with a transistor for activating the amplifier by connecting an impedance, in particular an inductance (24) for drain biasing, and the power combiner (1') comprises a tunable quarter-wavelength impedance transformer circuit (52) connected between the joining point of quarter-wavelength route transformers (51) and the output (S). The amplifiers (22) are Solid-State Power Amplifiers (SSPAs), eg. in the form of Monolithic Microwave Integrated Circuits (MMICs), and are controlled by the drain currents. The tunable quarter-wavelength transformer circuit (52) contains as many parallel branches as there are amplification routes, and each branch comprises two quarter-wavelength lines connected in series with the midpoint connected to the ground by the intermediary of an electronic interrupter; the interrupters are controlled so that only one is open at a time. The biasing point of amplifiers (22) is adjusted by the control circuit (6) as a function of the number of active amplifiers, and an increase in load impedance due to decreased numbers of active amplifiers is compensated by a decrease in the biasing currents. The power divider (1') comprises a tunable attenuator (11) controlled as a function of input power measured by a power sensor (61), and the number of amplifiers to be activated is determined according to the required output power. The output power measured by a power sensor (64) is compared to the required output power, and the functioning of amplifiers is verified according to the difference between the two quantities. The device with redundancy comprises two amplifier devices connected in parallel with outputs connected to switching elements for inactivating one of the two amplifier devices when a fault is detected.
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