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In these modern yearss where radio applications have become of import communicating devices have caused the current market to necessitate more and more wireless devices to be available for clients. Different wireless devices operate at different frequence band.For illustration the common footing for 3G webs will be CDMA ( 1.9 GHz ) and Bluetooth Technology that is runing at set ( 2.4 GHz ) . These applications are required in the latest cellular phones in the market [ 1 ] . Therefore, holding a double set device will heighten the mobility of the user as the device can be used in many states as it covers more frequency sets [ 2 ] .

LNA Introduction

Figure 1: LNA ina direct transition receiving system architecture.

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The pre-selection filter removes out of set signals and partly culls image set signals received by the aerial. These filtered signals will so be passed to the LNA which is a critical constituent in wireless devices as it amplifies the weak signal received. [ 3 ]

1.2.1 Double Band LNA

Planing a double set LNA will increase the serviceability of the radio devices so that it can work on 2 frequence sets, therefore doing it more various and relevant to the new tendency market of multiple usage devices.The double set device will increase the mobility of the users. Many states have different wireless criterion for its cellular system, which uses different frequence sets. As explained in the debut before, each application utilizes different frequence set hence the double set LNA is required to be able to run into multiple ( double ) frequence bands.Having a double set device will besides heighten the mobility of the user as the device can be used in many states as it covers more frequency sets.

1.3 Undertaking Aim

By making this undertaking, the low noise amplifier used in the microwave field can be studied and explored deeper. This undertaking is besides done to get the better of the individual set amplifier. The intent of planing this double set low noise amplifier is to open up a new scope of frequences runing from 1.9 GHz to 2.4GHz. This opens up a new path to the academic field and besides the industrial field as most of the engineering in this epoch uses frequence sets to convey information. The double set low noise amplifier enables the peculiar equipment to have more than one set at a clip compared to the individual set amplifier. The information transferred from a farther finish might acquire lost midway and noise might besides happen when a individual set bit is used together to have multiple sets. It can besides assist salvage infinite in boards by utilizing fewer french friess. The design of double set amplifier will get the better of all the jobs faced by currents users.

1.4 Technical Aims

Technical Aims

1.

To be able to cognize the operational theory of a individual set and double set receiving systems

2.

To be able to cognize the theory of low noise amplifier ( LNA ) amplifier

3.

To be able to make a double set receiving system to get the better of the disadvantage of individual set receiving systems

4.

To be able to fit the electric resistance and noise at two frequence scopes

5.

To be able to utilize Advanced Design System ( ADS ) to imitate the consequences

6.

To be able to run into the specifications for the parametric quantities in the tabular array below:

Parameters

Specifications

Addition

a‰? 16 dubnium

Noise Figure ( NF )

a‰¤ 2.4 dubnium

Unconditional stableness, ( K )

& gt ; 1

Input ( ) and end product ( )

a‰¤ – 10 dubnium

Low scope frequence

( 1.8 GHz – 2.0 GHz )

High scope frequence

( 2.3 GHz – 2.5 GHz )

Chapter 2: Literature Reappraisal

The double set LNA designing have been attempted by people with different frequence sets used for different applications. This chapter intends to give an overview of some basic rules used in the analysis and design of double set low noise amplifier. The most ambitious undertaking is the choice of the most suited devices for application such as the transistor in a LNA circuit. It is usually based on its features and S-parameters that correlate with its public presentation in the whole system at a ulterior phase. Researches on double set LNA antecedently challenged by other people are tabulated in Table 1 below:

Frequency Sets

( 174Hz -240 Hz ) and ( 1450 Hz -1490 Hz )

( 480MHz – 880MHz ) and ( 1.4GHz -1.67GHz )

( 868-915 ) MHz and 2.4 GHz )

( 2.4GHz and 5.2GHz )

( 2.45GHz ) and ( 5.25GHz )

Table 1: Double Band LNA challenged by other people

2.1 Double Band Low Noise Amplifier Design

The topology adopted in this undertaking to accomplish the double set frequence is to plan a wideband LNA that is able to have frequences runing from 1.9GHz and 2.4 GHz. Planing a double set LNA presents a considerable challenge because of its coincident demand for high addition, low noise figure, good input and end product matching and unconditioned stableness at the lowest possible current draw from the amplifier operating at both frequences. Although addition, noise figure, stableness and input and end product lucifers are all every bit of import, they are mutualist and do non ever work in each other ‘s favour. The selected transistor should exhibit high addition, low noise figure, and offer high third-order intercept point ( IP3 ) public presentation at the lowest possible current ingestion, while continuing comparatively easy fiting at frequence of operation. [ 4 ]

2.2 Dispersing Parameters ( S-parameters ) of a two port web

Figure 1: Incident and reflected moving ridges for a two-port

As seen on the figure shown supra, any going moving ridge nowadays in the circuit is made up of two constituents. For case, the entire traveling-wave constituent fluxing from the end product of the two-port device to the burden is really made up of that part of which is reflected from the end product of the two-port device together withthe part of that is transmitted through the two-port device. Similarly, the entire travelling wave fluxing from the input of the two-port device back toward the beginning is made up of that part of that is reflected from the input port plusthat fraction of that is transmitted through the two-port device. S-parameters relate to the going moving ridges that are scattered or reflected when a web is inserted into a transmittal line of certain characteristic electric resistance, ( Zo ) .

When these observations are set in equation signifier, the undermentioned expression will be obtained:

Eqn. 1

Eqn. 2

where, =the input contemplation coefficient,

=the contrary transmittal coefficient,

=the forward transmittal coefficient,

=the end product contemplation coefficient. [ 5 ]

From eqn. 1, when is set to zero, so the can be obtained by the expression below,

which is a reflected moving ridge divided by an incident moving ridge and, hence, it is equal to the input contemplation coefficient. So now, the can be plotted on a Smith Chart and the input electric resistance of the two-port device can be found instantly. The same status can be applied on the eqn. 2 by puting the peers to zero,

The value for the transmittal coefficient can be obtained by the expressions below:

The and for all the above equation can be set to zero by coercing and to be equal to the characteristic electric resistance of the measurement system. Therefore, any moving ridge that is incident upon or is wholly captive and none is reflected back toward the two-port device. [ 5 ]

The input return loss ( is input contemplation coefficient ( ) expressed in dBs ( dubnium ) .

The addition ( ) is forward transmittal coefficient ( ) expressed in ( dubnium ) .

The end product return loss ( is end product contemplation coefficient ( ) expressed in ( dubnium ) . [ 5 ]

2.2.1 Stability

A major factor in the amplifier design is the possible stableness of the transistor. A transistor is considered stable if there is no end product signal when there is no input signal. In LNA, stableness cheque must be done on the device before the design can be started. The stableness of the Low Noise Amplifier or its inclination to hover at a scope of frequence can be calculated utilizing the Rollett stableness factor ( K ) equation.Before ciphering the stableness of a transistor with S-parameters, the intermediate measure must foremost be calculated:

=

The Rollett Stability Factor ( K ) is so calculated as:

If K & gt ; 1, so the device will be unconditionally stable for any combination of beginning and burden electric resistance. If K & lt ; 1, the device is potentially unstable and will most likely oscillate with certain combinations of beginning and burden electric resistance. [ 5 ]

The K-factor represents a speedy cheque for stableness at given biasing status. A expanse of the K-factor over frequence for a given biasing point should be performed to guarantee unconditioned stableness outside of the set of operation. The end is to plan an LNA circuit that is unconditionally stable for the complete scope of frequences where the device has a significant addition. [ 4 ]

2.3.2 Noise Figure

The debasement measuring of the signal-to-noise ratio ( SNR ) caused by constituents in a wireless frequence ( RF ) signal ironss is known as the noise figure ( NF ) . The factor is calculated from the ratio of the input SNR over the end product of SNR. [ 6 ]

Where = signal-to-noise ratios of input power

= signal-to-noise ratios of end product power

The noise figure ( NF ) is the noise factor, given in dBs ( dubnium ) :

2.3.3 Power Gain

The term addition used in RF transistors is usually referred to the power addition of the device instead than merely the electromotive force or current addition because of the myriad of electric resistance degrees which abound in RF circuitry. When an electric resistance degree alterations in a circuit, the electromotive force and current additions no longer intend anything. [ 5 ]

Figure 2: A two-port web driven by a signal beginning and terminated by a burden

The transducer power addition, is a map of the two-port web dispersing parametric quantities and of both signal beginning port contemplation coefficient and the burden port contemplation coefficient. [ 7 ]

The power addition, G is a map of merely the and two-port web dispersing parametric quantities. Power addition does non depend on the. [ 7 ]

where

The available power addition is a map of merely the and two-port web dispersing parametric quantities. Available power addition does non depend on. [ 7 ]

where and

2.3.4 Third Order Input Intercept Point ( IIP3 )

When an amplifier is assumed to be additive, the intersect point between the power in the 3rd order merchandise and cardinal tone is known as the 3rd order input stop point ( IIP3 ) . [ 8 ] The end product of the 3rd intercept point is known as OIP3.

Figure 3: IIP3 concept Figure 4: IIP3 measuring

The diagram shown in Figure 3 is the construct of IIP3 while Figure 4 is the IIP3 measuring diagram. The IIP3 construct is the consequence of a two-tone trial done to mensurate the IIP3. Two cardinal tones with same frequences are supplied to the circuit and due to non-linearities, the 3rd order intermodulation merchandises will be present at the end product, beside the cardinal frequences [ 9 ] . The equation used step IIP3 derived from the diagram in Figure 4 is shown below:

where= desired end product, difference between cardinal and 3rd merchandise end product.

IIPs and OIP3 is non critical in this double set LNA design as it is located at the receiving system subdivision, the power it receives at the input is ever low therefore it will ever remain at the additive part.

2.3.5 Bandwidth

The bandwidth can be defined as the difference between the upper and lower operating frequences which is typically measured in Hertz ( Hz ) . Bandwidth is theA frequence rangeA that a signal contains. An LNA normally works between a lower limit and maximal frequences, for illustration the lower frequence set for this undertaking is 1.9 GHz while the upper frequence set is 2.4 GHz therefore the bandwidth is 500 MHz.

2.5 Smith Chart

Smith Chart is one of the most utile graphical tools available to the RF circuit interior decorator. The chart was originally conceived back in the 1930s by a Bell Laboratories applied scientist named Phillip Smith, who wanted an easier method of work outing the boring insistent equations that frequently appear in RF theory. His solution, suitably named the Smith Chart, is still widely in usage. The chart can be used to stand for many parametric quantities including electric resistances, contemplation coefficients, dispersing parametric quantities, noise figure circles, changeless addition contours and parts for unconditioned stableness. [ 11 ] Figure 5 below is a diagram of the Smith chart used for electric resistance matching.

Figure 5: Smith Chart

2.4 Electric resistance Matching

The chief aim of making electric resistance matching is to maximise the power transportation and minimise contemplations from the burden. [ 5 ] For a two-port web, is normally done by adding an input fiting web towards the beginning and an end product fiting web towards the end product. These webs consist of an inductance ( L ) and a capacitance ( C ) known as the lumped elements. An illustration of input and end product fiting for a two-port web is shown in Figure 6.

Figure 6: Example of Input and Figure 7: Placing Lumped Components Out Matching Network [ 12 ] Basedaccording to Smith Chart Lines [ 12 ]

The series or shunt arrangement for lumped constituents in a matching web is based on the way where the current point is matched towards the centre ( 50a„¦ ) in the smith chart. The placing of constituents is shown in Figure 7. Matching process in this undertaking will be done through an optimisation characteristic which is available in the simulation package itself. Due to the regulation of pollex set in the industrial criterion, the specification set for and in this undertaking is

2.5 Transistors Selection

AA transistorA is aA semiconductorA deviceA used toA amplifyA and switchA electronicA signals. It is made of a solid piece ofA semiconductorA stuff, with at least three terminuss for connexion to an external circuit. Transistors made of different stuffs have different names such as those anterior developed that are made of silicon stuffs are categorized as ( Si ) and germanium stuffs are categorized as ( Ge ) while the modern microwave transistors such as those made of Ga arsenide are categorized as ( GaAs ) and indium stuffs ; ( InP ) . [ 13 ]

Microwave field-effect transistors ( FET ) escpecially GaAsFET have better advantages as it besides include metal semiconducting material FETs ( MESFET ) therefore they ‘re besides called high negatron mobility transistors ( HEMT ) . Therefore, the GaAs FET transistor is chosen to be used in this undertaking in planing a LNA with broad bandwidth that is able to cover the double set ( 1.9 GHz and 2.4 GHz ) desired.

The Avago ATF-55143 GaAs FET transistor has been chosen as it is an Enhancement Mode Pseudomorphic HEMT ( E-PHEMT ) which can supply high addition, high one-dimensionality, low noise and low power end product that is suited for radio applications.

Chapter 3: Design Methodology

This chapter depicts on the design development procedure based on the construct explained in chapter 2. The package used in planing and imitating the consequence of this undertaking is the Advanced Design System ( ADS ) .

3.1 AdvancedDesign System Software Overview

Advance Design System ( ADS ) is electronic design mechanization package system which is created by Agilent EEsofEDA, a Development squad of Agilent Technologies. It supports RF design applied scientists in developing all types of RF designs from simple to the most complex of RF microwave faculties. ADS let interior decorators to the full characterize and optimize designs. [ 14 ] Post processing capablenesss available allow informations pull stringsing utilizing custom looks, informations sing on different secret plans and specifications altering, all without re-simulating. The package library contains illustrations of templet, pre-configured schematics, informations shows, and trial benches in assisting design confirmation against measurings defined in the radio criterions specifications. Thus the ADS package is the preferable design tool selected for this undertaking.

3.2Dual Band LNA Design Procedure

Transistor Selection Based on Specifications

Design Biasing Circuit

Measure S-parameters utilizing AC circuits

Check Stability Conditions of Transistor

Design Matching Network

Simulate Results Using ADS package

Optimization

3.1 Transistor Biasing

The first process starts with biasing the selected transistor to guarantee that when it is DC biased at a proper operating point, it is able to accomplish the current demands that will subsequently be supplied to the whole circuit.

Figure 8: FET_Curve_Tracer Connection with ATF-55143

The FET_Curve Tracer from ADS templet is used to execute the transistor biasing process. By imitating this circuit, the I-V curve features of the colored transistor will be shown. The intent of this I-V curve is to find the operating point for the selected and.

3.2 DC Biasing Network Design and Simulation

A biasing web is needed for this LNA circuit in order to bring forth a changeless value of electromotive force and current to the transistor. The inactive biasing method is chosen to bias the ATF-55143 E-PHEMT transistor due to its simpler design because extra transistor or non needed as the current class. An active will necessitate excess transistor, which will be more expensive to the design.

This biasing is accomplished by utilizing a electromotive force splitter dwelling of two resistances, R1 and R2. The electromotive force for the splitter is derived from the drain electromotive force which provide a signifier of electromotive force feedback through the usage of R3 to assist maintain drain current invariable. The values of resistances R1, R2 and R3 are calculated utilizing the expression shown below [ 15 ] :

where

is the power supply electromotive force

is the device drain to beginning electromotive force

is the coveted drain current

is the current flowing through the resistance electromotive force splitter web

The is chosen to be at least 10X the normal expected gate escape current ( regulation of pollex ) . In this instance, it was cautiously chosen to be 0.5 ma. Calculations are done by replacing the values of obtained from the consequence of FET_Curve_Tracer shown in Chapter 4, Figure 16 into the expressions shown supra.

With the resistances values obtained from the computation above, the transistor prejudice web is constructed as shown in Figure 9 below.

Figure 9: DC biasing web design utilizing lumped constituents.

The DC biasing public presentation is done utilizing DC simulator while the consequences can be checked by the DC Annotation characteristic that is available in the Simulate bead down in ADS package itself. Additional tuning was done by cut downing the resistance and to accomplish the needed prejudice status of.

3.3 Parameter Analysis

Extra circuitry utilizing capacitances and inductances are combined to the DC biasing web to organize a typical ATF-55143 LNA with inactive biasing circuit as shown in Figure 10 below. Harmonizing to the datasheet in Appendix A, the high base on balls electric resistance fiting web dwelling of L1/C1 and L4/C4 contribute to resound figure, addition, fiting while capacitance C2 and C5 provide low electric resistance in-band RF beltway for the matching webs. Capacitors C3 and C6 provide low frequence RF beltway for R3 and R4 that provide low frequence expiration. The value of C3 and C6 besides provide expiration for low frequence commixture merchandises that will impact the IIP3 consequences. All these constituents are set to Discrete Optimization manner from the constituent belongingss.

Figure 10: Typical ATF-55143 LNA with inactive biasing circuit.

Two ports alternatively of footings were connected to the circuit and the footings were deactivated in order to imitate the noise figure. The whole circuit was compressed into a conventional symbol by utilizing the Create/Edit Schematic Symbol map. This compaction will turn the whole circuit into a constituent and stored in the package library.

In order to imitate the S-parameters of this circuit, the constituent must be connected to the S-param templet which can be obtained from the ADS package templet library. The templets and constituents are as shown in Figure 11 below.

Figure 11: Parameter Analysis Circuit.

Goal for each specification were set in the templet after the circuit in Figure 11 above is constructed. The optimisation and end templets were taken from Optim/Stat/Yield/DOE pallet while S-parameter and stableness factor templets were taken from the Simulation-S_Param pallet. The specification scenes are shown in Figure 12 below.

Figure 12: Specifications Settings for Dual Band LNA circuit.

3.4 Impedance Matching Design

The end product fiting web dwelling of a LC armored combat vehicle ( an inductance and a capacitance ) was added into the circuit as the simulation consequences for end product return loss ( ) shown in Chapter 4, Figure 18is far from making the specification set.

Figure 13: End product Impedance fiting circuit added into the circuit.

A combination of shunt inductance and series capacitance was chosen to fit the frequence to the centre point hence this matching web was added to the circuit as shown in Figure 13 above. The values for these two constituents were set to be optimized to acquire the value of. The simulation consequences for the end product fiting web added to the circuit are shown in Chapter 4, Figure 19.

3.5 OIP3 Simulation

The HB2Tone templet from ADS package templet library is used to imitate the OIP3 value. The scenes for harmonic balance templet were set as shown in Figure 15 below. Two frequence simulations will be done from this circuit. The first simulation will be set with frequence 1.9 GHz while the 2nd with 2.4 GHz as these frequences are the chief specifications for this undertaking. The frequence scenes will be keyed in the variable equation templet which is high-lighted in ruddy in the diagram below.

Figure 14: IIP3 Simulation Circuit.

3.6 Current Drain Measurement

The current drain is really of import as it is the chief current that guaranting the transistor produces a addition to the signal. Gate current is to turn on the LNA, but the Drain current is the 1 that amplifies the input signal. Without the current drain, it wo n’t be called an amplifier. Therefore, a investigation is placed in the circuit as shown in Figure 16 to mensurate the current drain of the whole circuit. The node which connects both electromotive force supply and the investigation must be named. In the circuit shown, the node is named “ a ” . At the same clip, the three nodes from transistor are named VG, VD and VS severally for simulation in order to obtain the of the concluding circuit.

Figure 15: Current Drain Simulation Circuit.

As explained in the DC biasing web antecedently, the consequences can be done by imitating the circuit utilizing DC simulator and consequences checked utilizing DC Annotation. The consequences will be shown in Chapter 4.

Chapter 4: Results & A ; Discussions

4.1Transistor Biasing

Figure 16: FET_Curve_Tracer Simulation Result ( ATF-55143 )

The consequences obtained from the FET_Curve_Tracer showed that when the ATF-55143 transistor is biased at and, the selected.

4.2 DC Network Biasing

The DC Annotation simulated consequences were plotted into a tabular array in the simulation consequences shown in Figure 17 below while a comparing between the fake consequences and biasing demand were tabulated in Table 2.

Figure 17: DC Network Biasing Results

Comparison

Transistor Biased

2 V

20 ma

0.55 V

Network Biased

2.008 V

20.60 ma

0.515 V

Table 2: Comparison of Network Biasing Results

As shown in the comparing tabular array above, the consequences from biasing web has met the transistor biasing demand therefore this circuit is suited to be used as a biasing web for the Dual Band LNA circuit.

4.3 Parameter Analysis Results

Figure 18: Parameter Analysis Results

Fake consequences for the parametric quantity analysis are shown in Figure 18 above. Consequences obtained from simulation are tabulated into Table 3 below to do a comparing between the consequences and specifications set for this undertaking.

Specifications

Purpose

1.9 GHz

2.4 GHz

Gain ( S21 )

a‰? 16 dubnium

17.524 dubnium

15.836 dubnium

Input Return Loss ( S11 )

a‰¤ -10 dubnium

-8.085 dubnium

-11.780 dubnium

Output Return Loss ( S22 )

a‰¤ -10 dubnium

-6.060 dubnium

-7.344 dubnium

Noise Figure, NF

a‰¤ 2.4 dubnium

0.268 dubnium

0.290 dubnium

Stability, K

& gt ; 1

0.903 dubnium

1.021 dubnium

Table 3: Fake consequences comparison towards specification.

Based on the comparing shown in Table 4, most of the parametric quantities have or near to accomplishing the specifications set. The lone parametric quantity which is far from making the specification is the end product return loss ( ) . Thereforean end product electric resistance duplicate web would be needed for the circuitin order to better the hapless consequence.

4.2: End product Impedance Matching Results

Figure 19: Electric resistance Matching Results

Fake consequences for the end product electric resistance fiting web added to the circuit are shown in Figure 18 above. Consequences obtained from simulation are tabulated into Table 5 below to do a comparing between the consequences and specifications set for this undertaking.

Parameters

Specifications

1.9 GHz

2.4 GHz

Gain ( S21 )

a‰? 16 dubnium

17.337 dubnium

16.147 dubnium

Input Return Loss ( S11 )

a‰¤ -10 dubnium

-11.343 dubnium

-13.194 dubnium

Outputt Return Loss ( S22 )

a‰¤ -10 dubnium

-16.204 dubnium

-18.327 dubnium

Noise Figure, NF

a‰¤ 2.4 dubnium

0.268 dubnium

0.290 dubnium

Stability, K

& gt ; 1

1.229 dubnium

1.165 dubnium

Table 4: Fake consequences comparison towards specification.

Based on the comparing shown in Table 5, all parametric quantities have achieved the specifications set. The interpolation loss ( ) ; for both frequence is more than 16 dubnium and input and end product return loss ( ) and ( ) are lower than -10 dubnium while NF for both frequences are less than 2.4 dubnium. This circuit is unconditionally stable as the stableness factor ; K for both frequences is more than 1.

Figure 20: Smith Chart Results

The smith chart on the left side shown in Figure 19 above is the fake consequence before adding the end product fiting web while the smith chart on the right shows the consequence after the matching web has been added to the circuit. Theoretically, the ( ) points should be matched to the centre point which is 50a„¦ but since the end product return loss ( ) specification set is a‰¤ -10 dubnium, and the optimisation procedure set for the two constituents ( LC armored combat vehicle ) have already met the needed specification, there is no demand to foster fit the towards the centre point.

4.3 OIP3 Simulation Results

Figure 21: OIP3 consequence with cardinal tone of 1.9 GHz.

From the OIP3 consequences at cardinal 1.9 GHz shown in Figure 20 above, the value were substituted into the expression shown in Chapter 2 for IIP3 measuring. The computations are shown below:

Figure 22: OIP3 consequence with cardinal tone of 2.4 GHz.

From the OIP3 consequences at cardinal 2.4 GHz shown in Figure 21above, the value were substituted into the expression shown in Chapter 2 for IIP3 measuring. The computations are shown below:

. 4.4 Current Drain Consequences

The current drain, consequences are plotted in table shown in Figure 23 below while a comparing tabular array for the transistor biased values, web biased value and concluding circuit simulation value are tabulated in Table 5.

Figure 23: Current drain and operating point consequences.

Comparison

Transistor Biased

2 V

20 ma

0.55 V

Network Biased

2.008 V

20.60 ma

0.515 V

Final circuit simulation

1.999 V

20.80 ma

0.513 V

Table 5: Comparison of Network Biasing Results

As seen in the comparing table shown supra, the value of, and somewhat varies a from one another. These alterations did non impact the overall circuit as all the addition and other specifications are still met.

4.5 Performance Comparison

Parameter

Performance at 1.9 GHz

Performance at 2.4 GHz

Ideal

Discrete

Ideal

Discrete

Table 6: Performance Comparison between Ideal and Discrete Component Value

Chapter 5: Decision

The low noise amplifiers ( LNAs ) are of import constituents as they are the first amplifying phase that the signal will run into one time received from the aerial in a receiving system concatenation. During the procedure of making this undertaking, it is learnt that microwave field-effect transistors are utile in planing a double set LNA aimed for radio applications as they produce low noise, high addition and most significantly low power ingestion. It is of import for the LNA to be able to cut down noise every bit much as possible and at the same clip amplifies the coveted signal to the undermentioned phase in a receiving system concatenation as unwanted noise are major hinderance in the receiving system system.

As for the package, ADS is a powerful simulation tool due its many templet illustrations and pre-configured schematics available in the package library, the computation and planing procedure has been made easier. A batch of new tools in this package which were really utile throughout the design procedure have besides been learnt.

The concluding circuit simulated public presentation has been tabulated in Table 7 below:

Parameters

Specifications

1.9 GHz

2.4 GHz

Accomplishment

Gain ( S21 )

a‰? 16 dubnium

17.337 dubnium

16.147 dubnium

Achieved

Input Return Loss ( S11 )

a‰¤ -10 dubnium

-11.343 dubnium

-13.194 dubnium

Achieved

Outputt Return Loss ( S22 )

a‰¤ -10 dubnium

-16.204 dubnium

-18.327 dubnium

Achieved

Noise Figure, NF

a‰¤ 2.4 dubnium

0.268 dubnium

0.290 dubnium

Achieved

Stability, K

& gt ; 1

1.229 dubnium

1.165 dubnium

Achieved

Table 7: Concluding Consequences

As a decision, the double set LNA design for 1.9 GHz and 2.4 GHz can be considered as a successful design since all the parametric quantities given in the specifications are satisfied.

There were jobs faced while making the design for the LNA. The simulations consequences for the LNA design with ideal constituents and distinct constituents were different. The simulation consequence for the end product return loss ( ) were non satisfied that is caused of the trade-off between addition, noise figure and stableness. There are times at the starting phase, frequently when one specification is met ; the others will be out of specifications. For illustration, when the constituents are optimized for Noise Figure, the other parametric quantities such as addition, stableness and input/output return loss will be affected. A batch of clip was spent on optimisation of the constituents in the double set LNA design.

Chapter 6: Recommendation

There are a few recommendations for future work such as:

Inclusion of the harmonic balance or IP3 ( 3rd order interception ) in the design.

The input return loss fiting web can be added to the circuit and both input and end product return loss ( can be farther matched to 50 Ohm.

Adding another phase in order to cover a wider scope of frequence sets.

The concluding layout of the design besides can be fabricated to a PCB board by adding microstirp transmittal lines and tested at existent clip utilizing spectrum analyser and so the consequence of the terminal merchandise and at the simulation degree can be compared.

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