Broadband Doherty power amplifier based on load modulation network

Abstract

The invention discloses a broadband Doherty power amplifier based on a load modulation network. The broadband Doherty power amplifier comprises a broadband power divider, a carrier power amplification module, a peak power amplification module and the load modulation network. The carrier power amplification module comprises a carrier input matching / biasing network, a carrier power amplifier, a carrier output matching / biasing network and a carrier power amplifier impedance conversion line; the peak power amplification module comprises a peak power amplifier phase compensation line, a peak input matching / biasing network, a peak power amplifier and a peak output matching / biasing network; and the load modulation network comprises a dual-band impedance transformer composed of a pi-shaped impedance transformer and an L-shaped branch line. According to the Doherty power amplifier, the load modulation network is used for ensuring the drain efficiency and the rollback efficiency of the Doherty power amplifier and expanding the bandwidth at the same time, and meanwhile, the Doherty power amplifier is compact in structure and beneficial to miniaturization design.

Description

technical field [0001] The invention belongs to the field of microwave radio frequency communication, relates to a radio frequency power amplifier, in particular to a broadband Doherty power amplifier based on a load modulation network. Background technique [0002] With the development of wireless communication technology, the demand for data traffic is increasing, there are more and more communication standards, and more and more frequency bands are occupied. As an important part of the RF front-end, the efficiency and bandwidth of power amplifiers have become research hotspots. Especially with the advent of the 5G era, higher requirements are placed on the fallback efficiency of power amplifiers. However, the efficiency of traditional power amplifiers is very low at high power fallback. In order to maintain the efficiency of RF power amplifiers at fallback power, Doherty topology is widely used in RF power amplification. However, the traditional Doherty structure has obv...

AI Technical Summary

Problems solved by technology

[0002] With the development of wireless communication technology, the demand for data traffic is increasing, there are more and more communication standards, and more and more frequency bands are occupied. As an important part of the RF front-end, the efficiency and bandwidth of power amplifiers have become research hotspots. Especially with the advent of the 5G era, higher requirements are placed on the fallback efficiency of power amplifiers. However, the efficiency of traditional power amplifiers is very low at high power fallback. In order to maintain the efficiency of RF power amplifiers at fallback power, Doherty topology is widely used in RF power amplification

However, the traditional Doherty structure has obvious narrow-band working characteristics, which limits its application scenarios

like figure 1 As shown, in the traditional Doherty structure, the 1 / 4 wavelength line will produce dispersion phenomenon as the frequency deviates from the center frequency, so that the output impedance and the load are not completely matched

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