JPS6234815U - - Google Patents

Description

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an ALC circuit according to an embodiment of the invention, FIG. 2 is a block diagram showing a conventional ALC circuit, and FIG. 3 is a timing chart of the ALC signal and main signal. 1 is a variable attenuator, 2 is a switch, 3a and 3b are 3
dB hybrid coupler, 4a, 4b are power amplifiers, 5 is a directional coupler, 6 is a control circuit, 7a, 7
b is a dummy resistor. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] In an auto level control circuit that controls the output level by detecting the output level and feeding back the level difference from the reference level to the input side, there is a variable attenuator that controls the level of the input signal, and a signal that is attenuated by the variable attenuator. a switching device that switches the signal at high speed and distributes it into an auto level control signal and a main signal; a distribution means that distributes the signal distributed by this switching device into two with a phase difference of 90 degrees; a pair of power amplifiers that amplify the respective signals, a combining means that combines the signals amplified by these power amplifiers by distributing them into two with a phase difference of 90 degrees, and the main signal of this combining means. a main system connected to one output port from which the auto-level control signal of the synthesis means is output, and a control means for controlling the variable attenuator according to the output level of the other output port from which the auto-level control signal of the synthesis means is output. An auto level control circuit.