Serially concatenated multi-level radio-frequency power amplifier and front-end transmitter

Abstract

The invention relates to the technical field of communications, in particular relates to a serially concatenated multi-level radio-frequency power amplifier which comprises a linearity compensation circuit and a power amplifier, wherein the linearity compensation circuit and the power amplifier are serially concatenated; the linearity compensation circuit comprises a primary radio-frequency amplifier and a bias circuit enabling the amplifier transistor to generate gain compression; and the power amplifier is biased at a class AB state. According to the invention, the circuit generating linearized compensation enables the bias current of the radio-frequency amplifier transistor of the level to increase along with the increment of input power through the adaptive adjustment of the bias circuit; the gain of the radio-frequency amplifier transistor is increased in the case of relatively higher power input so as to generate gain expansion; and by serially concatenated the primary radio-frequency amplifier transistor with the next level of amplifier, the generated gain expansion can be used for compensating the gain compression of the next level of amplifier so as to improve the linearity of the power amplifier.

Description

technical field [0001] The invention relates to the field of communication technology, in particular to a series-cascaded multi-stage radio frequency power amplifier and a front-end transmitter. Background technique [0002] With the evolution of modern wireless communication towards high-speed and large-capacity, users' requirements for broadband communication continue to increase, and the next-generation technology is becoming more and more demanding on the performance of radio frequency and microwave power amplifiers. Regardless of 3G's long-term evolution project (LTE, LongTerm Evolution), or IMT-Advanced technology compatible with TD-LTE, RF power amplifiers have similar technical characteristics, requiring lower signal distortion and higher signal peak-to-average power ratio. . In order to transmit a signal with a higher peak-to-average power ratio without distortion, the power amplifier must not only meet the transmission requirements under the average power output, ...

AI Technical Summary

Problems solved by technology

[0003] But at the same time, a problem that has to be faced is that the RF power amplifier is essentially a nonlinear device, which will produce unwanted intermodulation distortion products, which will directly affect the quality of the RF signal

The distortion introduced by the RF amplifier will cause the amplified signal to be distorted in amplitude and phase. The greater the input power, the more obvious its nonlinear characteristics, and when the modulated signal with a certain bandwidth passes through the power amplifier, an intermodulation component will be generated. , causing spectrum expansion, causing interference to adjacent channel signals, directly affecting the bit error rate of the receiving system, and deteriorating the performance of the communication system

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