Standing wave detection circuit

Abstract

The invention discloses a standing wave detection circuit, which comprises a bidirectional coupling circuit, first and second power attenuators, first and second power dividers, a detector and an amplitude error detection circuit, and is characterized in that the bidirectional coupling circuit is used for coupling power of forward signals and reverse signals, the forward signals are outputted to the first power attenuator after coupling, and the reverse signals are outputted to the second power attenuator; the first power attenuator carries out amplitude adjustment on the received forward signals and the signals are then outputted to the first power divider; the second power attenuator carries out amplitude adjustment on the received reverse signals and the signals are then outputted to the second power divider; the first power divider divides the received signal power into two parts, and the two parts are outputted to the detector and the amplitude error detection circuit respectively; and the second power divider carries out power division on the received signals, and the signals are then outputted to the amplitude error detection circuit. The standing wave detection circuit can be widely applied to various power amplification circuits and wireless communication systems.

Description

Technical field [0001] The invention relates to a detection circuit, in particular to a standing wave detection circuit. Background technique [0002] The RF power amplifier is an important part of various wireless transmitters, and its cost usually accounts for more than 50% of the entire wireless communication system. Therefore, the power amplifier circuit is often designed with protection and detection circuits, of which the standing wave detection circuit is particularly important. The power amplifier located at the front end of the antenna is most sensitive to the deterioration of the standing wave, and the difference in the degree of the deterioration of the standing wave ratio has different effects on the power amplifier: when the deterioration of the standing wave ratio is small, the impact on the power amplifier will not be too great, and the standing wave ratio deteriorates Too large will affect the communication distance and reduce the quality of information transmissi...

AI Technical Summary

Problems solved by technology

At present, most of the standing wave detection circuits are relatively rough detection circuits with low precision, and it is impossible to measure the detail of the deterioration of the standing wave ratio, but only to judge whether the standing wave ratio has deteriorated; the insertion loss is large, and the insertion loss brought by the detection circuit is relatively large. Affect the output power of the main circuit of the power amplifier; the sensitivity is low, and it cannot be detected when the standing wave ratio is less than 1.5.

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