Advanced Design System

Advanced function SystemDESIGN AND ANALYSIS OF A SINGLE-STUB NOTCH permeate USING AGILENTS ADVANCE DESIGN SYSTEM (ADSTM)ABSTRACT The purpose of this case study is to acquire an idea on the visualize of single- butt notch gain vigors victimisation Agilent ripe design system (ADSTM). By properly calculating the required breadth, distance and founding passage of the single butt end notch slobber using ADS champion can design a notch filter which can block frequencies not required. In the small airstrip layout when wavelength of the stub is , the open circuit of the stub is converted to short circuit and foreshadows along the notch filter atomic weigh 18 blocked. By adjusting the breadth and using various functions like line calc the parameters of the filter be compute and the filter is designed and analysed. Agilent advanced system is an in force(p) software for the analysis of the microwave links.INTRODUCTION Advanced Design System (ADSTM) Advanced Design System i s the industry leader in high- relative frequency domain design. It supports electronic systems and RF design engineers developing all types of RF designs, from simple to the most complex, from RF or microwave modules to be integrated MMICs for conversations and aerospace/defense applications.ADS is With a complete set of simulation technologies ranging from frequency, time, numeric and physical domain simulation to electromagnetic playing area simulation, ADS lets designers fully characterize and optimize designs. The single, integrated design, GUI graphical user interface environment provides system, circuit, and electromagnetic simulators, along with schematic capture, layout, and verification capability eliminating the starts and gelt associated with changing design tools in mid-cycle.ADS can be used for virtual prototyping, debugging, or as an aid in manufacturing test. To enhance engineering productivity and sign up time-to-market, ADS software offers a high level of desig n automation and applications intelligence. This proven software environment is easily extensible we can customize ADS by adding features focussed on your particular application needs. An AD runs on PCs and workstations, with complete file compatibility between platforms and across networks. 8Advanced Design Systemis a authorityful electronic design automation software used by leading companies in the wireless communication networking and aerospace defence industries. For WiMAX, LTE, multi-gigabit per second data links, radar, satellite applications, ADS provides full, s topazdards-based design and verification with tuner Libraries and circuit-system-EM co-simulation in an integrated platform.Key Benefits of ADS Complete, integrated set of fast, accurate and easy-to-use system, circuit EM simulators enable first-pass design success in a complete backcloth flow. Application-specific Design Guides encapsulate years of expertise in an easy-to-use interface.Components used in (AD STM) systemTerm (Port Impedance for S-parameters)Parameters screamDescriptionUnits indifferenceNumPort numberInteger1ZReference immunity, use 1+j*0 for complexOhm50NoiseEnable/disable port thermal haphazardness yes, no (for AC or harmonic balance analysis only not for S-parameter analysis)noneyesV(DC)Open circuit DC voltage no(prenominal)NoneTempTemperatureoCNoneTable1 Parameters of TermNoteTerm can be used in all simulations. For S-parameter simulations it is used to define the impedance and hole of the ports. When not in use, it is treated as an impedance with the value R + JX. The reactance is ignored for dc simulations.MLOC (Micro strip Open-Circuited Stub)MLOC symbolMLOC IllustrationParametersNameDescriptionUnitsDefaultSubstSubstrate instance nameNoneMSub1W debate width mil25.0LLine lengthmil100.0Wall1Distance from near abut of strip H to first sidewall Wall1 1/2 Maximum( W, H)mil1.0e+30Wall2Distance from near edge of strip H to second sidewall Wall2 1/2 Maximum( W, H) mil1.0e+30TempPhysical temperature (see Notes)CNoneModChoice of dispersion modelNoneKirschningTable 2 Parameters of MLOCRange of utilisation1Er 128 0.01 100Where, Er = dielectric immutable (from associated Subst) H = substratum thickness (from associated Subst)Recommended Range for different dispersion modelsKirschning and Jansen 1Er 20 0.1HW 100HKobayashi 1 Er 128 0.1H W 10H 0 H0.13Yamashita 2 Er 16 0.05H W 16HWhere, = wavelength freq 100 gigacycle per secondNotes and Equations 1. The frequency-domain analytical model uses the Kirschning and Jansen formula to calculate the static impedance, Zo, and effective dielectric never-ending, Eeff. The attenuation factor, , is calculated using the incremental inductance rule by Wheeler. The frequency dependence of the skin effect is included in the conductor exhalation calculation. Dielectric loss is also included in the loss calculation.2. Dispersion make are included using either the improved version of the Kirschning and Jansen model, the Kobayashi model, or the Yamashita model, depending on the survival of the fittest specified in Mod. The program defaults to using the Kirschning and Jansen formula.3. For time-domain analysis, an impulse receipt obtained from the frequency analytical model is used.4. The Temp parameter is only used in noise calculations.5. For noise to be generated, the transmission line must be lossy (loss generates thermal noise).6. To turn off noise contribution, set Temp to 273.15C.7. When the Hu parameter of the substrate is less than 100H, the enclosure effect volition not be properly calculated if Wall1 and Wall2 are left blank.8. Wall1 and Wall2 must satisfy the following constraints Min(Wall1) 1/2Maximum(W, H) Min(Wall2) 1/2Maximum(W, H)MLIN (Micro strip Line)MLIN symbolMLIN IllustrationParametersNameDescriptionUnitsDefaultSubstSubstrate instance nameNoneMSub1WLine widthmil25.0LLine lengthmil100.0Wall1Distance from near edge of strip H to first sidewall Wall1 1/2 Maximum( W, H)mil1.0e+30Wall2Distance from near edge of strip H to second sidewall Wall2 1/2 Maximum( W, H)mil1.0e+30TempPhysical temperature (see Notes)CNoneModChoice of dispersion modelNoneKirschningTable 3 Parameters of MLINRange of Usage 1 ER 128 0.01 100Where, ER = dielectric constant (from associated Subst) H = substrate thickness (from associated Subst)Recommended Range for different dispersion modelsKirschning and Jansen 1 Er 20 0.1 H W 100 HKobayashi 1 Er 128 0.1 H W 10 H 0 H 0.13 Yamashita 2 Er 16 0.05 H W 16 HWhere = wavelength freq 100 gigahertzNotes and Equations1. The frequency-domain analytical model uses the Hammerstad and Jensen formula to calculate the static impedance, Zo, and effective dielectric constant, eff. The attenuation factor, , is calculated using the incremental inductance rule by Wheeler. The frequency dependence of the skin effect is included in the conductor loss calculation. Dielectric loss is also included in the loss calculatio n.2. Dispersion effects are included using either the improved version of the Kirschning and Jansen model, the Kobayashi model, or the Yamashita model, depending on the choice specified in Mod. The program defaults to using the Kirschning and Jansen formula.3. For time-domain analysis, an impulse response obtained from the frequency analytical model is used.4. The Temp parameter is only used in noise calculations.5. For noise to be generated, the transmission line must be lossy (loss generates thermal noise).6. To turn off noise contribution, set Temp to 273.15C.7. When the Hu parameter of the substrate is less than 100 H, the enclosure effect will not be properly calculated if Wall1 and Wall2 are left blank.8. Wall1 and Wall2 must satisfy the following constraints Min(Wall1) 1/2 Maximum(W, H) Min(Wall2) 1/2 Maximum(W, H)MTEE (Microstrip T-Junction)MTEE symbolMTEE IllustrationParametersNameDescriptionUnitsSubstMicrostrip substrate nameNoneW1Conductor width at pin 1MilW2Conducto r width at pin 2MilW3Conductor width at pin 3MilTempPhysical temperatureCTable 4 Parameters of MTEERange of Usage0.05 H W1 10 H 0.05 H W2 10 H 0.05 H W3 10 H Er 20 Wlargest/Wsmallest 5 where Wlargest, Wsmallest are the largest, smallest width among W2, W2, W3 f(GHz) H (mm) 0.4 Z0 Z0 is the indication impedance of the line with WlargestNotes and Equations1. The frequency-domain model is an empirically based, analytical model. The model modifies E. Hammerstad model formula to calculate the Tee junction discontinuity at the location defined in the reference for wide range validity. A reference plan shift is added to each of the ports to make the reference planes consistent with the layout.2. The center lines of the strips connected to pins 1 and 2 are assumed to be aligned.3. For time-domain analysis, an impulse response obtained from the frequency-domain analytical model is used.4. The Temp parameter is only used in noise calculations.5. For noise to be generated, the transmission line must be lossy (loss generates thermal noise). Single-stub notch filterIn Radio Communication Systems, undesired harmonics are generated. A micro strip notch filters undesired harmonics in a narrow band device like a mobile phone.A Notch filter is a device that passes all frequencies except those in a stop band middled on a centre frequency. The quality factor plays a major office staff in eliminating the frequencies undesired. Quality factor (Q) of a band pass or notch filter is defined as the centre frequency of a filter divided by the bandwidth.Where, bandwidth is the difference between frequency of the upper 3dB roll off point and frequency of the lower 3dB roll off point.TRANSMISSION note of hand THEORY place to another for directing the transmission of energy, such as electromagnetic waves or acoustic waves, as well as electric power transmission. Components of transmission lines include wires, coaxial cables, dielectric slabs, optical references, electri c power lines, and waveguides.Consider the micro strip layout of a notch filter,In the designing of the micro-strip circuits (i.e. filters), the canonical parameters are impedance Z0 and guide wavelength g which are considered as TEM transmission line.The impedance in the open circuit stub Zin is as given below,Zin = ZSWhere ZL=, so we ignore ZS Zin = ZS = ZS = ZS = j ZS cot lHowever,l = , l = =Therefore, cot l=0So, Zin = -j ZS cot l=0hence L = = / = 1so VSWR = = 2/0 =This indicates that the signal whose wavelength is will have very low impedance and hence it is a short circuitThus presentation loss response at frequency f0 is high except for other frequencies, this is because cot l is no protracted zero. interposition loss and return loss are two important data to evaluate the quality of many passive fiber optic fractions, such as fiber optic conciliate cord and fiber optic connector and many more.Insertion lossDefinition The Insertion Loss of a line is the ratio of the power authorized at the end of the line to the power transmitted into the line.Insertion loss refers to the fibre optic light loss caused when a fibre optic component insert into another one to form the fibre optic link. Insertion loss can result from absorption, misalignment or air gap between the fibre optic components. We want the insertion loss to be as less as possible. Our fibre optic components insertion loss is less than 0.2dB typical, less than 0.1dB types functional on request.An expression for insertion loss is IL= 10log10 1 +(YS/2)2 collapse lossReturn Loss is a measure of the reflected energy from a transmitted signal. It is ordinarily expressed in positive dBs. The larger the value, the less energy that is reflected.Return loss can be calculated using the following equationIMPRLT10.gif (1294 bytes)Return loss is a measure of VSWR (Voltage Standing Wave Ratio), expressed in decibels (db). The return-loss is caused due to impedance mismatch between two or more ci rcuits. For a simple cable assembly, there will be a mismatch where the connector is connected to the cable. There may be an impedance mismatch caused by bends or cuts in a cable. At microwave frequencies, the material properties as well as the dimensions of the cable or connector plays important consumption in determining the impedance match or mismatch. A high value of return-loss denotes better quality of the system down the stairs test (or device under test). For example, a cable with a return loss of 21 db is better than another similar cable with a return loss of 14 db, and so on.Phase Response of the notch filterThe phase response of a notch filter shows the greatest rate of change at the centre frequency. The rate of change becomes more rapid as the Q of the filter increases. The group delay of a notch filter is greatest at the centre frequency, and becomes longer as the Q of the filter increases.EXPERIMENT SUB PARTSCASE-STUDY PART 1AimDesigning and simulation of a notch f ilter at 3 GHz using Agilents ADSTM for the given design specifications.Requirement Electrical cognitive make shopping center frequency 3.0 GHzInsertion loss 25.0 dBInput/ output Impedance 50 Substrate specificationsMaterial type 3M Cu-cladDielectric constant (r) 2.17 weightiness (h) 0.794mmConductor thickness (t) 35umConductivity () 5.84e+7 S/mtan 0.0009MLIN, MLOC and MTEE are micro strip elements defined in ADSTM which is used to construct the circuitExplanationWe need to simulate and design a notch filter at 3 GHz here, using Agilents ADS. When the above specifications are used in ADS, the width of the microstrip lines is obtained as 2.42mm corresponding to 50 ohms transmission line using Line calc function.The Line Calc function is also used to determine the effective dielectric constant (Keff) of 3M Cu-clad Substrate at 3.0GHZ from which the initial, length of the open circuit stub can be calculated.r = 2.1 Keff = 1.854 at 3.0GHZ (from line calc) , 0 = 100 m (at 3.0 GHZ) g = 0 /(Keff)1/2 = 100/(1.854)1/2 =73.44mm g/4 =18.36 mm The initial design length of the open circuit stub is 18.354 mm.Thus we obtain the following substrate specifications at Centre frequency 3.0 GHz, Insertion loss greater than 25.0 dB and Input/output ImpedanceMaterial type 3M Cu-Clad, Dielectric constant (r) 2.17, Thickness (h) 0.794m,Conductor thickness (t) 35um, Conductivity () 5.84e+7 S/m, tan=0.0009, l = 18.36mm W(Width of the micro strip lines)=2.42mmFrom these specifications we obtain the plot of Insertion Loss Response(S21) indicating about 49.234 dB attenuation near 3 GHz which is shown in 8To observe the effect of varying the length of the open circuit stub , the same procedure of simulation is repeated twice or thrice with different values of length of open circuit stub given as follows L1=20, L2=18.34, L3=16.As we can see in the 9 that as the length of open stub increases the frequency decreases. As the length of open stub must be g/4 and so the 50 micro strip line is b locked and hence the signal is passed and if there is change in the length then the micro strip is not blocked hence the signal is blocked.Analysis of the case study 1From the case study1, it proves that at wavelength g/4 the open circuit at point S of the stub is alter to short circuit and the signals passing along AB micro strip is blocked. Thus we design a filter at 3 GHz frequency.When the wavelength is g/4 the signal will see very low impedance to ground at point S and hence is short circuited. This signal will be absorbed from the signals applied at input A, which will manifest high attenuation in its insertion loss at 3GHz.All other signals anticipate unaffected, hence low insertion loss accept near 3GHz.CASE-STUDY PART 2AimUsing the ADSTM Tuning installment, investigate the effect of varying the width of the stub filter. Determine the width of line which provides minimum out of band loss whilst maintaining the original filter specifications (i.e.25 db at 3.0 GHz)Requireme ntElectrical performanceCentre frequency 3.0 GHzInsertion loss 25.0 dBInput/output Impedance 50 Substrate specificationsMaterial type 3M Cu-cladDielectric constant (r) 2.17Thickness (h) 0.794mmConductor thickness (t) 35umConductivity () 5.84e+7 S/mtan 0.0009CS2 10 Circuit Diagram of Stub Notch filter obtained by ADS SimulationExplanationWhen the width of the stub is 5mm and length is 18.8mm the response obtained is as shown belowNow we vary the width of the stub to investigate the effect. . In this process the width of the stub filter is changed at different values from w1=5mm, w2=2.5mm, w3=2mm, w4=1mm, w5=0.2mm as shown in 12. Here we also note that when varying the width of line, both the width of the stub line and corresponding width on the MTEE section must is varied.After varying the width using tuning fork function of the ADS facility we obtain a response at 3GHz and width is noted as 0.2mm.The 13 shows the following.Analysis of case study 2The width of the line determines its impedance. If the impedance is high thinner the line and viceversa.When the width of the i/o transmission line is equivalent to the width of the stub then Insertion loss is at 0Db and when width of the i/o transmission line is greater than the width of the stub then Insertion loss tends to 0Db.In the above case and so we vary the width of the stub and transmission line and when centre frequency is 3 GHz and the width is 0.2mm the insertion loss is very low. Lower the insertion loss more is the signal transmitted.CASE- STUDY PART 3AimTo design a notch filter at centre frequency of 4.5GHZ and it should blue-pencil the spurious signal and unwanted harmonics by at least 24db with minimum out of band loss with the specifications given belowRequirementElectrical specificationsCentre frequency 4.5 GHzInsertion loss 25.0 dBInput/output Impedance 50 Substrate specificationsMaterial type 3M Cu-cladDielectric constant (r) 2.17Thickness (h) 0.794mmConductor thickness (t) 35umConductivity () 5.84e+7 S/mtan 0.0009Explanation In the responses shown below we have obtained the 24 dB difference by adjusting the frequency at 4.5 GHz. In CS3 14 the length and width are adjusted to obtain the particular responseAnalysis of case study 3In case study 3 we understand the way of designing a notch filter to cancel the spurious signals generated by wireless communication systems.CONCLUSIONThis case study helps us analyse the notch filter. The notch filter is designed and its basics and working are understood. The tool ADS proves very effective in this learning. To conclude, this experiment gives us a broader knowledge about transmission theory. The concept is deeply understood. In wireless communications the unwanted harmonics and spurious signals generated are cancelled by this notch filter enabling a better reception. Thus designing of such a notch filter is learnt.