CN203434935U

CN203434935U - Low noise amplifier with microstrip line matching structure

Info

Publication number: CN203434935U
Application number: CN201320392481.6U
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: 2014-02-12
Anticipated expiration: 2023-07-03

Abstract

The utility model discloses a low noise amplifier with a microstrip line matching structure. The low noise amplifier with the microstrip line matching structure comprises an input end matching structure, a first transistor, a stage matching structure, a second transistor and an output end matching structure. The input end matching structure is connected with the first transistor, the stage matching structure, the second transistor and the output end matching structure in sequence. The input end matching structure, the stage matching structure and the output end matching structure are the T-shaped microstrip line matching structures with a parallel branch being a stub line. According to the microstrip line matching structure, the precise size of a microstrip line enables the capacitance inductance value equivalently formed to be more accurate, signal crosstalk caused by lumped parameter components is eliminated, the defect that the performance is not stable is avoided, standing wave performance is improved, the bandwidth can be broadened, the structure is simple, and performance is stable.

Description

A kind of microstrip line coupling low noise amplifier

Technical field

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

Utility model content

For the problems referred to above, the utility model 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 forms equivalence is also more accurate, has eliminated the signal cross-talk that lumped parameter components and parts bring, the shortcoming that performance is stable not, standing wave performance is improved, can expand bandwidth simultaneously, simple in structure, stable performance.

In order to address the above problem, the technical solution adopted in the utility model is:

A coupling low noise amplifier, comprises input coupling, the first transistor, interstage matched, transistor seconds and output coupling; Wherein, input coupling is connected with the first transistor, interstage matched, transistor seconds, output coupling successively.

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

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

As further preferred version of the present utility model, the T-shaped microstrip line that described parallel branch is stub, its dimensional accuracy is 0.1mm.

The utility model compared with prior art, has following technique effect: adopt 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.

Accompanying drawing explanation

Fig. 1 is 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, the technical solution of the utility model is described in further detail:

As shown in Figure 1, the utility model 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 the high electron mobility field effect transistor that the model of the AVAGO company of employing is ATF-54143, its operating frequency is that 450MHz is to 6GHz, gain is 20.4dB, noise factor is 0.5dB, by its chip data, by software, can calculate the resistance value of fan-out mouth, then according to the resistance value that calculates gained, the size of microstrip line is calculated, matched circuit two ends.

The matching structure of microstrip line has two kinds of modes conventionally: the T-shaped microstrip line matching structure that the T-shaped microstrip line matching structure that parallel branch is short circuit and parallel branch are 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 also more approaches ideal state, and circuit just can be more stable.

By reference to the accompanying drawings execution mode of the present utility model is explained in detail above, but the utility model is not limited to above-mentioned execution mode, in the ken possessing those of ordinary skills, can also under the prerequisite that does not depart from the utility model aim, make a variety of changes.

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, input coupling is connected with the first transistor, interstage matched, transistor seconds, output coupling successively.

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