2 of the Microstrip Calculator, h=H1 and b=H2-H1. Impedance (Ω): The desired impedance. INPUT DATA. 02 m Slotline Equation. 1< w/h < 3. I would like to know how to compute the impedance at the edge of a microstrip patch in CST. To use this calculator, enter the values for the wire diameter and substrate dielectric and press the "calculate" button. 2 Effective Permittivity and Characteristic Impedance; 4. Large selection of online interactive calculators for RF design, including attenuators, capacitance, resonance, RF traps, and microstrip impedance. The JLCPCB Impedance Calculator computes track width values and recommended stack-ups from user-input values of board layer, thickness, copper weight, target impedance, trace spacing (for edge-coupled pairs), and impedance trace to copper gap (coplanar waveguides). microstrip line are assumed to be quasi-TEM, and dispersion along the microstrip line is taken into account using the empirical formulas given in Appendix C. coupledmicrostrip = coupledMicrostripLine creates a default coupled microstrip transmission line with a Teflon substrate and default properties for a resonating frequency of 1. Inputs Trace Thickness Substrate Height Trace Width Trace Spacing Dielectric Constant Outputs. Assuming that there is no loss in the transmission process, the characteristic impedance of the antenna can be expressed by the distributed capacitance C per unit length and the phase velocity Vp:Overview. I have a question. This form of microstrip is composed of two traces. This example is based on Problem 5. Microstrip Impedance. Following is the list of useful converters and calculators. If the ratio (L/W) is close to unity, the radiation pattern will be symmetric but may not provide a resonable input impedance. Include both the pcb dielectric thickness as well as the wire insulation in the height calculation. Some of them include Microstrip, Stripline and Coplanar Waveguide. 48 e -0. The stepped-impedance lowpass microstrip filters, which use a cascaded structure of alternating high- and lowimpedance transmission lines. 1. INPUT DATA. The characteristic impedance of your microstrips is determined by the trace width for a given layer stackup. Note the stub is attached in parallel at the source end of the primary line. Following equation or formula is used for Microstrip Width Calculator. Pi-Matching Impedance Network Calculator. Visit to learn more about the EEWeb communit. Description. Impedance Matching pins of IC to microstrip line. 8. Symmetric Stripline Impedance Calculators and Formulas; To really see how the trace widths for these transmission lines compare, we need to plot the characteristic impedance vs. The calculator then uses a formula to calculate the width and spacing of the trace or transmission line required to achieve the desired characteristic impedance. W is the width of the microstrip trace. *Comparisons show minimal differences to ADS linecalc and Polar Instruments Quicksolver industry standard tools. 2-side PCB, one side with signals, the other with GND. The new version includes: This software is intended to assist with microwave circuit design in predicting the impedance of a circuit made with Rogers High Frequency. This calculator will help you calculate the guided wavelength, provided the dimensions of the microstrip are given as well as the velocity of propagation, the microstrip material's dielectric constant, and the input frequency. Calculate impedance from resistance and reactance in parallel. RF Calculators. Select the Calculate button to calculate the characteristic impedance of the trace and the effective relative permittivity. For example, with microstrip, you can specify the substrate parameters (primarily thickness and dielectric constant) and use Linecalc to calculate the impedance for a given line width; this is the “analysis” mode. W is the Width of track. The impedance of a differential via pair cannot be treated with a single via impedance calculator unless the vias are spaced far apart. Dual Stripline. Microstrip lines are used to convey microwave -frequency signals. Impedance (Z o ): 76. All About Circuits is the largest online electrical engineering communities in the world with over 700K engineers, who collaborate every day to. Microstrip Impedance Calculator. The characteristic impedance (Z o) of a microstrip transmission line can be calculated using the active calculator or the equations at the bottom of the page. A Microstrip is a type of electrical transmission line used to transmit RF signals and are commonly fabricated using printed circuit board (PCB) technology. There are 3 types of microstrip models to choose from- uncoated, coated, and embedded. With hundreds of coaxial RF cables in-stock and ready to ship worldwide immediately, our coax capacitance calculator lets you calculate the impedance of a coax by allowing you to enter the outer diameter dielectric width and inner conductor diameter. Differential Microstrip Impedance From Zo. Dipole Antenna Calculator. 15 mm spacing. This calculator is designed to calculate the characteristic impedance of an edge coupled microstrip. This calculator is designed to calculate the characteristic impedance of a broadside couple stripline (see diagram below). If, in addition to a differential impedance (Z Diff), you also need a defined Z 0, proceed as follows:. For example, coupledMicrostripLine (Length. To use this calculator, simply input your microstrip geometry and Dk value, and the tool will return the differential impedance value for a pair of microstrip traces. The solver is quasi-static because the solution does not include the high-frequency dispersion that takes place in microstrip lines (higher concentration of fields in a dielectric with higher dielectric constant at high frequencies). Note: Units do not matter for this calculation as long as they are consistent. As an important part of the electronic radio frequency device, such as microstrip antennas, 1,2 resonant antennas, 3 microstrip line is the carrier and the transmission tool of energy and information. Microstrip Impedance Calculator. 3): fHigher-Microstrip = c/(4h εr − 1− −−−−√) = 10. Z diff = 2* Z o (1 - 0. You may also check it on amazon. I use FR-4, so H=1. Microstrip Characteristic Impedance Calculator Using a Formula by Brian C. This tool will also compute the resistance of the stripline, the voltage drop on it, and the resulting power dissipation. Agilent's LineCalc tool calculates Z odd = 50. Line Width (W) in mils. It renders fairly accurate results suitable for use in circuit board manufacturing and engineering analysis. where Z 0,surf can be computed as specified in Eq. Not all calculators will explicitly state this. USB traces must be 90 Ohms differential. Microstrip Line Calculator Analyze or synthesize a microstrip line based on substrate parameters and frequency. These are considered to be standardized impedance values with cables readily available. Introducing the newest version of the Microwave Impedance Calculator from Rogers’ Advanced Connectivity Solutions. The Calculator Calculates the values of the Characteristic Impedance, Capacitance per unit length and propogation speed. While commonly constructed using printed circuit boards, this structure can also be built using other materials as long as the…Analyze. Enter the values of trace width (w), trace thickness. For a case of dielectric constant of 4. Also, any two models that agree with the data to better than. If you need to find and use an efficient and accurate microstrip impedance calculator that provides lossless impedance values, you can use our free tool below. Unequal-split Power Divider Calculator. 37) If H1<1. Reset. Printed Circuit Board (PCB) RF Microstrip Calculator with Formulas. The characteristic impedance represents the ratio of voltage to current in a transmission line and is a critical parameter in ensuring signal integrity and impedance matching in high-frequency electronic circuits. Coplanar wave guide with ground plane. 2 Low Impedance; The formulas developed in Section 4. A major advantage of a radial stub is that the input impedance presented to the through line generally has broader bandwidth than that obtained with the. Figure 5. Procedure: • We know the standard characteristics impedance of microstrip line to be of 50Ω. This page of converters and calculators section covers microstrip line impedance calculator. Resistance in mOhm/inch. 4. Calculate characteristic impedance of transmission line: layout: Plot all metal layers and board. Attenuator Calculators. Wire Self Inductance. The result of a Schwarz-Christoffel mapping is used to find the radial gap capacitor. The PCB Impedance Calculator in Altium Designer. Each of the transmission lines consists of a signal trace and a reference plane(s). The substrate parameters (ε r and h) are required. 1. Enter values for W and L for a microstrip line to determine its Zo and Electrical Length. Result. Sorted by: 1. 32 and the equation shown in 5. Note that this defines the bandwidth given the operating frequency and wavelength in free space: Microstrip patch antenna bandwidth A Microstrip Patch Antenna CalculatorOverview. Compared to waveguides, microstrip is generally has a lower power handling capacity, and higher losses due to the fact that it is not enclosed. Characteristic Impedance of the System (Z0) Ohms. Differential microstrip impedance calculator is an online electronic tool to measure the opposition to alternating current. When I google “impedance calculators pcb” this website is the first hit. beammy. This microstrip impedance calculator gives you a good start for estimating the trace width and PCB dielectric thickness that will produce a target impedance value. The Calculator assumes that 1. 1 of the Microstrip Calculator using H2 in place of h, εr,eff can be computed as specified in Eq. Microstrip Impedance Calculator Provide values for three of the four parameters H, T, W, Z 0 and the relative permittivity of the dielectric. The edge couple differential microstrip transmission line is a common technique for routing differential traces. The reflection coefficients at each boundary in Figure 7. T-Match Topology. 3: Normalized characteristic impedance and normalized effective permittivity of a microstrip line as a function of u = w / h. The original source of formula is IPC-2141: Controlled Impedance Circuit Boards and High-Speed Logic Design, April 1996. Use an online differential microstrip impedance calculator; Use an online differential stripline impedance calculator The lateral dimensions, however, are well controlled being photolithographically defined and then etched. Calculates the characteristic impedance and per-unit-length parameters. JLCPCB Impedance Calculator. INPUT DATA. For example, if you wish to input "25000000", just type "25M" instead. RF calculations and RF conversions include metric. even if i calculate in these deviations from standard i still dont get the same results as the web calculator and calculations by the standard are different from web calulator results as well. November 15, 2023 Maurizio Di Paolo Emilio. 3) (4. EEWeb offers a free online broadside coupled stripline impedance calculator. 2. 6 Band Resistor. It is a ribbon wire (signal line), separated from the ground plane by a dielectric. 3 Answers. Geometric Parameter Definitions: Saturn PCB - Toolkit for Impedance Calculation. Cross-hatched copper plane in a flex stack-up for controlled impedance. 0300) creates a microstrip line of length 0. Following equation or formula is used for Differential Microstrip Impedance Calculator. The width of the conducting layer is important to calculate the radiation intensity since it directly affects. For budgetting reasons I'm tied to a stock pooling layer stackup, so I went for OSHpark's 4-layer stackup (35um copper - 0. Equation 5. Polar or rectangular grids only allow direct reading of S11. (1) When the characteristic impedance (Zo) of the line width (w) is calculated. A great example is the surface microstrip which forms on the outer layers of the PCB. This function calculates the line impedance and the phase velocity of a microstrip line. 2 are defined as. Altium Designer’s differential line impedance calculator will set up your impedance-controlled differential pair routing widths for you. EEWeb offers a free online microstrip crosstalk calculator. For example, a 2 inch microstrip line over an Er = 4. Radar Calculators. View All Tools. to NF. With this PCB impedance calculator, you can calculate the microstrip controlled impedance or the impedance of a variety of conductors in a printed circuit board. With PCBWay impedance calculator, you can calculate the approximate impedance of your PCB / high frequency circuit board. Microstrip Impedance Calculator: Provide values for three of the four parameters H, T, W, Z0 and the relative permittivity of the dielectric. Calculate the Differential Microstrip Impedance of a transmission line based on the the distance between the strips, height of the substrate, trace thickness and dielectric constant of the substrate. For example, if u = 1 and ε r = 10, then from the figure, Z 0 ε e = 126 Ω and ε e / ε r = 0. The amplitude of this crosstalk is what this tool calculates. More. Where: Z 0 is the characteristic impedance of the microstrip; ε r is the relative permittivity (dielectric constant) of the substrate material; h is the height of the microstrip above the. coplaner waveguide spacing. CPW consists of a central strip flanked by two metal half-planes that carry the return current. Microstrip Impedance Calculator. Microstrip Calculator computes a microstrip's height/width ratio, impedance and relative dielectric constant for a microstrip transmission line. This calculator finds both odd and even transmission line impedance. ferent methods for calculating the input impedance of microstrip antenna. Equation Source: Ulaby "Fundamentals of Applied. We recommend the software from Polar Instruments if you want to get exact impedance calculation. This calculator determines the impedance of a symmetric differential stripline pair. Either the desired impedance at a specific frequency is used to determine the waveguide width, or the width is entered and the impedance is calculated. This tool helps you create a matching circuit so that optimal power transfer occurs between unmatched loads. To use this tool, enter the values for. Analysis for a desired circuit type and material. Pasternack's Microstrip Calculator computes a microstrip's height/width ratio, impedance and relative dielectric constant for a microstrip. For this reason, trace width is important in the design of striplines. Where a Microstrip Line Calculator Fails. While this calculator will provide a baseline, any final design considerations should be made towards loss, dispersion, copper roughness, phase shift, etc. Select the box with the geometry that you would like to calculate. What is a Microstrip Impedance Calculator? This is a calculator used for determining the characteristic impedance of a microstrip. The range of accepted values is 20 to 90 Ω for single-ended and 50 to 150 Ω for differential signals. Values for L and C will be calculated for the four. The edge couple differential symmetric stripline transmission line is a common technique for routing differential traces. The characteristic impedance of “narrow” ( W ≪ h) microstrip line can be roughly approximated by Equation 7. This calculator is heavilly based on . 1: Impedance-matching using a quarter-wavelength transmission line. The inductance of a PCB trace determines the strength of any crosstalk it will receive. ±1% in h, ±2% in ±1% in C. For simple cases it's just applying the formula found all over the internet or use one of the online calculators. 3. If I calculate trace as a microstrip then 0. λ is the wavelength of the signal in free space. Embedded Microstrip. The wire microstrip transmission line is similar to a standard microstrip transmission line, but with a round conductor. For more information see About. The IPC-2141 trace Impedance calculator will help make initial design easier by allowing the user to input basic parameters and get a calculated impedance according to the IPC-2141 standard. Inductance Calculators. Description. The twisted pair helps create a more uniform inductance and capacitance per unit length of wire to ensure a constant impedance, by keeping the return path as close to the signal as possible. Thickness: Thickness of the microstrip conductor. microstrip = microstripLine (Name=Value) sets properties using one or more name value pair arguments. A cross-section of a microstrip transmission line is shown below. Provide values for three of the four parameters h, t, w, Z 0 and the relative permittivity of the dielectric. SAVE & ACCEPT. A microstrip width calculator can calculate the width of a microstrip. At low frequencies near 0 GHz, the input impedance is inductive since. In both cases, you’ll need to enter your stackup information into the calculator to get accurate results. Email: info@multi-circuit-boards. Figure 2. The microstrip a. I have been trying to find a formula to calculate the impedance of an embedded microstrip where the substrate has a different dielectric constant to the superstrate (so the stack up is conducting plane - dielectric substrate - trace - dielectric superstrate) - with no luck so far. That means on ten mil (254 micron) alumina, the width for fifty ohm microstrip will be about 9. 1t + 2. General Device Efficiency Comparisons in Power Supply Designs. 4mil and the dielectric thickness to the first intermediate layer (this is a 4-layer board) is 6. Yes, any dielectric above will have an effect, although not a large one since most of the field is below the microstrip. For microstrip, you can (approximately) cut metal losses in half by doubling the dielectric thickness and keeping the same system impedance. This transmission line calculator was. This assumes ~0 trace thickness. Assume microstrip line for which propagation occurs with. Table 1 shows some free impedance calculators on the internet. Matlab/Freemat file 1. Result: Microstrip Patch Antennas (or simply patch antenna) are increasingly useful because the antenna is printed directly onto a circuit board. These tools seamlessly integrate with the rest of your design tools in a. The edge couple differential symmetric stripline transmission line is a common technique for routing differential traces. Microstrip impedance calculator Mixer spur calculator mmWave Link Budget calculator Noise Figure/Temp converter Optimal Mitre calculator Path loss calculator. The input impedance, Zin, of the shorted microstrip line is shown in Figure 3. Asymmetric Stripline Impedance Overview. Note that if the wire is insulated, then the results of this calculator will just be an estimate. Download a free microstrip taper calculator worksheet. Just enter the given values for trace thickness, substrate heights, trace width and subtrate dielectric in the calculator above and press the "calculate. The effective dielectric constant drives the length of the taper, this effect was not. To use this calculator, enter the width of the trace, its separation (measured from the center), the thickness of the trace, and the relative. L-Match Topology. Visit to learn more about our other electrical engineering tools and resources. The image below shows the calculated real part of the characteristic impedance of a microstrip and stripline on FR4 (Dk = 4. For example, going from 10 mil to 20 mil alumina, or two-mil to four-mil GaAs. A microstrip patch antenna is one of the most popular microwave antennas. Just to give designers a starting point, take a look at these differential impedance calculators you can use to get an initial estimate of the differential impedance for microstrips and striplines. , GND or VCC) below it constitutes a microstrip layout. Basic Calculator. The Smith Chart graphically maps S11=reflection coefficient= (ZL-Z0)/ (ZL+Z0) to Load Impedance (ZL), normalized to Z0 (source impedance = center of chart). Input Zo, and click on [ Synthesis ] button. ThePCB Impedance Calculator. Figure 5. You may enter custom values or choose from a list of commonly. Reset. *Accurate for arbitrary values of Er and w/h ratios. Based on the assessment in the Polar Instruments article, Wheeler’s method appears to be the most accurate method for calculating microstrip. The stripline impedance calculator provided below is useful for gaining an initial estimate of trace impedance for striplines. Adjust the distance "s". Go to the. For example, if u = 1 and ε r = 10, then from the figure, Z 0 ε e = 126 Ω and ε e / ε r = 0. 34. The amplitude increases as the coupling length increases up to a point. Coplanar Waveguide Calculator. The microstrip calculator determines the width and length of a microstrip line for a given characteristic impedance (Zo) and electrical length or vice versa. 352278 [-] coupling =-9. coupledmicrostrip = coupledMicrostripLine (Name=Value) sets Properties using one or more name-value arguments. In fact, striplines often make components such as band-pass filter's more accurately, with more symmetric roll-off and no lower cutoff frequency. Click the button corresponding to the unknown parameter to calculate its value. This transmission line calculator. Microstrip Mitred Bend Formula or Equation. This can be achieved by regulating the inner and outer diameter of the coaxial cable, along with the. It is a useful tool in the design and analysis of microwave circuits, particularly in the fields of communication, radar, and satellite systems. To use this calculator, simply input your microstrip geometry and Dk value, and the tool will return the differential impedance value for a pair of microstrip traces. To use these to design for a target impedance, simply cycle through various geometric values for the trace width until the calculator returns the target impedance. The impedance bandwidth of the antenna is 2. 1 High Impedance; 4. 0; 1 < ε r < 15 ) Select the units for all dimensions: mm mils. Characteristic Impedance [ohms] Coupling Coefficient [-] Even Mode Impedance [ohms] Odd Mode Impedance [ohms] Electrical Length [degrees]A cross-hatch plane is shown in the image below. 0 dielectric would have a delay of about 270 ps. To use the calculator, place values in either the velocity of propagation field or the dielectric constant field. 0 Dimensional units: mm milsh is the height of the microstrip line above the ground plane. The surface roughness of the conductor. Following is the list of useful converters and calculators. To use this calculator, enter the values for the wire diameter and substrate. Z = R + jX, where j is the imaginary component:. Reset. As seen from the formula when D decreases, while keeping H constant, Zdiff decrease. Γ0 = Z01 − ZS Z01 + ZS Γn = Zn + 1 − Zn Zn + 1 + Zn ΓN = ZL − Z0N ZL + Z0N. This allows you to double check the calculator and make sure that it selected appropriate values, by making sure the impedance correctly matches the input impedance. The complex characteristic impedance is given by the equation: Z 0 = R 0 + j X 0. The formula includes dispersion, so a frequency vector has to be defined. Relative Dielectric Constant ( εr ): Track Width. dBm to Watt converter Stripline Impedance calculator Microstrip line impedance Antenna G/T Noise temp. 1t for W/h ≤ 1 and Wr = W + 1. Edge Coupled Stripline Impedance Calculator. This online microstrip impedance calculator calculates the characteristic impedance of the microstrip (Ω), W/H ratio, and effective dielectric constant (εe) by entering the value of dielectric material relative. 1, the top (visible) traces comprise one conductor, whereas the ground plane (underneath, so not. Once the dialog is open a segment to use for the impedance calculation can be defined by either: Selecting it in the dialog opened by "Segment List". This antenna does not take any much extra size and can be etched on the same mobile PCB itself. I have only Saturn PCB SW to make some calculations. Microstrip Transmission Line Models. If there is an insulator around the wire then this calculator will be an estimate. The calculator shown below uses Wadell’s equations for differential impedance, which can be found in the seminal textbook Transmission Line Design Handbook. It also determines the wavelength and the length adjustment. There are multiple tools on Internet to calculate the net width to use. 60. This is actually a general way to express impedance, but it requires an understanding of complex numbers. The parasitic capacitance and inductance created by nearby conductors. Microstrip Mitred Bend Calculator. From impedance matching theory, you can calculate the characteristic impedance of a quarter wave transformer, by this equation: Zc = sqrt (Zo*ZL) Where Zc is the characteristic impedance of the quarter wavelength line, ZL is the load impedance and Zo is the impedance you are matching to. Using typical values of W = 8 mil, H = 5 mil. Matlab/Freemat file 1. TransCalc is an open-source impedance calculator of various transmission lines based on common closed-form approximations. Typical thickness of an LPI mask over the traces is . These calculators will return an impedance value for pairs of trace width, substrate thickness, and copper weight values. 1mm FR4 in between yealds about 50 ohms. As seen here:Figure 3. A coupled line RF filter was designed and working prototypes of the design performed well. Wheeler’s equations for microstrip trace impedance. We recommend the software from Polar Instruments if you want to get exact impedance calculation. (2) When the line width (w) of the characteristic impedance (Zo) is calculated. 37 mil, H = 30 mil and T = 1. In some cases, users require a custom impedance value. Click here to see the user guide of our impedance. Coplanar wave guide. Microstrip Impedance Calculator Note: valid for (w/h) from 0. This can be achieved by regulating the inner and outer diameter of the coaxial cable, along with the. Figure 7. Dielectric Thickness (h) Dielectric Constant (εr) Calculate. • Animating the field plot. The inductance of a rectangle loop has three geometric variables: W – rectangle long side. Note that the "h", for dielectric thickness in this formula is omitted in some other Polar publications. A differential stripline pair refers to two traces located between two reference plane layers, which are routed as a differential pair. Nowadays, devices are more complex and delicate, so more appropriate calculations can increase the functionality of PCBs and devices. Total Capacitance in pf. 243 [ohm] coupling = 0. c) The wavelength of the line at 10 GHz. For typical PCB parameters (ε r = 4, H 1 = 61. A simple microstrip is located on the top of the board, while an embedded microstrip is located inside the board substrate as illustrated below. October 18, 2023 Maurizio Di Paolo Emilio. 60. To use this calculator, enter the values for the wire diameter and substrate dielectric and press the "calculate" button. Stripline vs. Hallmark Circuits, Inc. Microstrip Patch Antenna Calculator Calculate dimensions and edge impedance for desired resonant frequency. The surface finish is neglected. The coax is a good way to create a transmission line. microstrip target impedance: 50 Ω. 6 mils line width, and the effective dielectric constant is 6. A solution to the problems of microstrip is coplanar waveguide (CPW) shown in Figure [Math Processing Error] 3. In some cases, users require a custom impedance value. I have been fiddling around with GPS antenna trace impedance matching. The microstrip. Incidentally, the trace thickness parameter does have a. 3. These values are usually represented in mil. 5 mils (241 microns). 08. We know that ZL in this case is 50 ohms, due to the. example. Usually Microstrip separated from the ground by using dielectric substrate. Single-stub matching is a very common method for impedance matching using microstrip lines at frequences in the UHF band (300-3000 MHz) and above. By adding the formulas of the dielectric and copper, a similarly simple formula of total attenuation is obtained. 11ad wimax Zigbee z-wave GSM LTE UMTS Bluetooth UWB IoT satellite Antenna RADAREXAMPLE: INPUTS : Relative Dielectric Constant = 4. My summaryThis page of converters and calculators section covers microstrip line impedance calculator. When in doubt, use 1 for copper, . 5. Also, take into consideration the board's dielectric thickness and. In most practical cases, the dielectric substrate is electrically thin, that is, (h ≪lambda). A differential stripline pair refers to two traces located between two reference plane layers, which are routed as a differential pair. To help you run through the above integral, you can download a microstrip trace taper calculator worksheet for use in Excel. The substrate parameters (ε r and h) and the. Select the units for all dimensions: mm mils. 6. The high-impedance lines act as series inductors and the low-impedance lines act as shunt. Cadence’s suite of PCB design and analysis tools can assist you in designing microwave and RF circuits. This value was. Input Zo, and click on [ Synthesis ] button. As you route traces on a real board, they can couple to other traces and conductors capacitively or inductively. To calculate this, you need some values. Ensuring impedance-controlled routing also requires knowledge of the substrate’s dielectric constant and your required trace width. 6 GHz f Higher-Microstrip = c / ( 4 h ε r − 1) = 10. 5 / 2) Zo = 64. The calculator utilizes the formula for calculating the impedance of a microstrip trace: Impedance (Z) = [87 / √(ε + 1. One challenge in designing PCB interconnects is maintaining system impedance while reducing crosstalk, which requires reducing trace inductance. A stripline is similar to the microstrip except that the flat conductor is now.