CN103391051A

CN103391051A - Microstrip line matching low noise amplifier

Info

Publication number: CN103391051A
Application number: CN2013102764617A
Authority: CN
Inventors: 马婷
Original assignee: WUJIANG TONGXIN ELECTRONIC TECHNOLOGY Co Ltd
Current assignee: WUJIANG TONGXIN ELECTRONIC TECHNOLOGY Co Ltd
Priority date: 2013-07-03
Filing date: 2013-07-03
Publication date: 2013-11-13

Abstract

The invention discloses a microstrip line matching low noise amplifier, which comprises an input end matching part, a first transistor, a stage matching part, a second transistor and an output end matching part, wherein the input end matching part is connected with the first transistor, the stage matching part, the second transistor and the output matching part in sequence. The input end matching part, the stage matching part and the output end matching part all adopt T-shaped microstrip line matching structures of which parallel branches are stub lines. By adopting the microstrip line matching structures, the precise sizes of microstrip lines enable equivalent capacitance and inductance values to be more accurate, the defects of signal crosstalk and unstable performance caused by lumped parameter components are eliminated, standing wave performance is improved, and meanwhile, bandwidth is expended, the structure is simple, and the performance is stable.

Description

A kind of microstrip line coupling low noise amplifier

Technical field

The present invention relates to a kind of low noise amplifier, particularly a kind of microstrip line coupling low noise amplifier.

Background technology

crystal amplifier is one of amplifier the most classical on history, use transistor to carry out the amplifier usage comparison of cascade extensive, simultaneously transistor is carried out the lumped parameter coupling, namely so-called capacitor and inductor mates, but use capacitor and inductor but can be with the inevitable problem of serving, easily produce on the one hand some signal cross-talks on circuit board due to capacitor and inductor, cause the standing-wave ratio of port poor, rosin joint also easily occurs on the other hand, the impacts such as device failure, circuit easily has problems, when circuit board greatly to a certain extent the time, search also very difficult, in addition, the value of present patch capacitor inductance is approximation, and accurate not, can only look for substitute, so these problems all become the crystal amplifier problem demanding prompt solution.

Summary of the invention

For the problems referred to above, the invention discloses a kind of microstrip line coupling low noise amplifier, adopt the structure of microstrip line coupling, the capacitor and inductor value that the accurate size of microstrip line makes equivalence form is also more accurate, has eliminated the signal cross-talk that the lumped parameter components and parts bring, the shortcoming that performance is stable not, the standing wave performance is improved, simultaneously can expand bandwidth, simple in structure, stable performance.

In order to address the above problem, the technical solution used in the present invention is:

A kind of microstrip line coupling low noise amplifier, comprise input coupling, the first transistor, interstage matched, transistor seconds and output coupling; Wherein, the input coupling is connected with the first transistor, interstage matched, transistor seconds, output coupling successively.

As the present invention further optimization scheme, it is the T-shaped microstrip line matching structure of stub that described input coupling, interstage matched, output coupling all adopt parallel branch.

As the present invention further optimization scheme, it is the high electron mobility field effect transistor of ATF-54143 that described the first transistor and transistor seconds all adopt model.

As the present invention further optimization scheme, described parallel branch is the T-shaped microstrip line of stub, and its dimensional accuracy is 0.1mm.

The present invention compared with prior art, has following technique effect: adopt the microstrip line coupling, improved standing-wave ratio, expanded bandwidth; Interstage matched is more stable, and circuit signal is crosstalked little; Simple in structure, practical reliable, stable performance.

Description of drawings

Fig. 1 is the circuit system module map.

Fig. 2 is the T-shaped microstrip line matching structure schematic diagram of stub.

Embodiment

Below in conjunction with accompanying drawing, technical scheme of the present invention is described in further detail:

As shown in Figure 1, the invention discloses a kind of microstrip line coupling low noise amplifier, comprise input coupling, the first transistor, interstage matched, transistor seconds and output coupling, wherein Input matching, the first transistor, interstage matched, transistor seconds and output coupling are connected successively.Signal is successively through Input matching, the first transistor, interstage matched, transistor seconds and output coupling, and amplification is exported through two-stage.

The first transistor and transistor seconds are all that the model of the AVAGO company of employing is the high electron mobility field effect transistor of ATF-54143, its operating frequency is that 450MHz is to 6GHz, gain is 20.4dB, noise factor is 0.5dB, can calculate the resistance value of fan-out mouth by its chip data by software, then according to the resistance value that calculates gained, the size of microstrip line is calculated, matched the circuit two ends and get final product.

The matching structure of microstrip line has dual mode usually: parallel branch is the T-shaped microstrip line matching structure of short circuit and the T-shaped microstrip line matching structure that parallel branch is stub.In the present embodiment, what input coupling, interstage matched, output coupling adopted is that parallel branch is the T-shaped microstrip line matching structure of stub, as shown in Figure 2.Because the size of microstrip line can be as accurate as 0.1mm, the value of the capacitor and inductor that the accurate size equivalence of microstrip line forms is also very accurate, and by the coupling of microstrip line, the coupling of circuit is more accurate, and circuit is also more near ideal state, and circuit just can be more stable.

The above is explained in detail embodiments of the present invention by reference to the accompanying drawings, but the present invention is not limited to above-mentioned execution mode, in the ken that those of ordinary skills possess, can also make a variety of changes under the prerequisite that does not break away from aim of the present invention.

Claims

1. a microstrip line coupling low noise amplifier, is characterized in that: comprise input coupling, the first transistor, interstage matched, transistor seconds and output coupling; Wherein, the input coupling is connected with the first transistor, interstage matched, transistor seconds, output coupling successively.

2. a kind of microstrip line as claimed in claim 1 mates low noise amplifier, it is characterized in that: it is the T-shaped microstrip line matching structure of stub that described input coupling, interstage matched, output coupling all adopt parallel branch.

3. a kind of microstrip line as claimed in claim 1 mates low noise amplifier, and it is characterized in that: it is the high electron mobility field effect transistor of ATF-54143 that described the first transistor and transistor seconds all adopt model.

4. a kind of microstrip line as claimed in claim 1 or 2 mates low noise amplifier, and it is characterized in that: described parallel branch is the T-shaped microstrip line of stub, and its dimensional accuracy is 0.1mm.