Ultra-wideband low-noise amplifier based on improved impedance matching network

Abstract

The invention discloses an ultra-wideband low-noise amplifier based on an improved impedance matching network. The ultra-wideband low-noise amplifier comprises a first amplification circuit used for carrying out primary amplification on an ultra-wideband signal and a second amplification circuit, an interstage impedance matching network used for realizing impedance matching of the first amplification circuit and the second amplification circuit, a second amplification circuit used for further carrying out secondary amplification on an ultra-wideband signal, and an output buffer used for carrying out output impedance matching on the second amplification circuit, which are connected in sequence. Each amplifying circuit comprises a negative feedback matching network consisting of an inductor,a resistor and a capacitor and is used for carrying out ultra-wideband input impedance matching on the amplifying circuit. According to the ultra-wideband low-noise amplifier based on the improved impedance matching network, by improving the input impedance matching network, the interstage impedance matching network and the output impedance network, mutual restriction between the matching networkand other performance such as a noise coefficient is relieved to a certain extent, and the ultra-wideband low-noise amplifier has good performance; and the circuit is simple in structure and small inoverall area.

Description

technical field [0001] The invention belongs to the field of radio frequency integrated circuits, in particular to an ultra-wideband low-noise amplifier based on an improved impedance matching network. Background technique [0002] In most receiving systems, low noise amplifiers usually appear as the first stage of active circuits. Since the received signal is usually weak and cannot be processed directly, a low-noise amplifier is required to amplify it with a certain gain. At the same time, according to the noise theory, the larger gain of the front-end circuit can effectively suppress the impact of the rear-stage circuit. Contribution to overall noise. In addition, as a first-stage circuit must have sufficiently small noise, because its noise figure will completely add to the overall noise figure. [0003] With the continuous development of radio frequency technology, low noise amplifiers often need to have some new functions on the basis of satisfying the basic function...

AI Technical Summary

Problems solved by technology

[0004] With the in-depth research on ultra-wideband low-noise amplifiers, scholars have proposed several more classic topological structures, but these structures are limited in application due to their own shortcomings.

The source-level degenerate inductive amplifier has a small bandwidth. The broadband filter network amplifier introduces excessive noise and also occupies a large chip area. The resistor feedback amplifier needs to sacrifice certain noise performance in order to obtain a larger bandwidth. Distribution The design of the amplifier is complex and the circuit area is too large due to the cascading of multiple tubes.

The emergence of these shortcomings is often related to the mutual constraints between the matching network and other properties such as noise figure

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