Low noise amplifier using multipath noise counteraction

Abstract

The present invention discloses a low noise amplifier circuit adopting multiplex noise counteract, wherein the low noise amplifier includes a DC connected Balanced to Unbalanced transformer (Balun), a pair of cross coupling connected input transistor with source electrode respectively direct connected to two balancing ends of the Balanced to Unbalanced transformer and the grid respectively AC coupled connected to two balancing ends that different with Balanced to Unbalanced transformer; a pair of transistor load with the grid respectively AC coupled connected to two balancing ends of the Balanced to Unbalanced transformer, and two pairs of electric resistance-capacitance (R-C) high-pass filter network forms cross coupling configuration by connecting the input transistor, two pairs of electric resistance-capacitance high-pass filter network AC couples the input signal to grid of the transistor load tube. The main purpose of the present invention is to realize low noise coefficient and high linearity through multiplex noise counteract technology only consuming low power consumption at the same time.

Description

technical field [0001] The invention relates to a low noise amplifier, in particular to a low noise amplifier circuit with low power consumption and high linearity, and belongs to the technical field of radio frequency integrated circuits. Background technique [0002] With the development of wireless communication technology and integrated circuit technology, the research of low noise amplifier has been widely concerned. The low-noise amplifier is an important part of the front-end of the radio frequency integrated circuit receiver. It is mainly used to amplify the weak signal received by the antenna for subsequent module processing. LNAs not only need to have very low noise figure, but also need to have high linearity and consume as little current as possible. Traditional low-noise amplifiers usually use a common-source amplification structure with source inductance feedback. This structure can obtain a lower noise figure, but requires the use of on-chip inductors, which ...

AI Technical Summary

Problems solved by technology

[0007] 1. The noise contribution of the source DC bias part 101 and the load part 103 is usually very large and cannot be ignored, which leads to the fact that the actual noise figure of the circuit is usually much greater than the theoretical minimum value;

[0008] 2. When the circuit is used in a narrowband radio frequency receiver system, the source DC bias part 101 and the load part 103 usually need to use on-chip spiral inductors to obtain better performance, which will increase the design difficulty and chip area, and the cost will be higher. High; and when the circuit is applied to a wideband radio frequency receiver system, parts 101 and 103 can only use resistors or transistor active devices, which contribute a lot to the noise of the whole circuit, and the performance is often difficult to meet the actual application requirements

Images