81. calculate the surface impedance instead of using scaled surface impedance. The S-parameters are influenced by several factors, namely the via placement, spacing to planes and copper pour, and the via density. This function converts of a set of conventional, 2-port, single-ended S-parameters into a 1-port differential impedance. You're looking for a differential coplanar waveguide calculator. 2 Conventional Coplanar Waveguide on an Infinitely Thick Dielectric Substrate 17 2. The calculator below uses Wadell’s. Connecting the side grounds to the lower ground using vias suppresses the. The Gap Waveguide technology utilizes an Artificial Magnetic Conductor (AMC) to prevent the propagation of electromagnetic (EM) waves under certain conditions, resulting in various gap waveguide configurations. 3 Conventional Coplanar Waveguide on a Dielectric Substrate of Finite Thickness 20 2. The calculator shown below uses Wadell’s equations for differential impedance, which can be found in the seminal textbook Transmission Line Design Handbook. Whinnery and T. Description. 30 Aug 2010 Can anyone provide Grounded Differential Coplanar Waveguide calculator? Thanks in advance. 0 of permitivity) at. This technique is preferably used in a multilayer PCB design, and the signal trace is backed either with or without by the ground. A differential stripline pair refers to two traces located between two reference plane layers, which are routed as a differential pair. The structures studied include conductor-backed and. The S-parameters are influenced by several factors, namely the via placement, spacing to planes and copper pour, and the via density. - Dk is the property of a material which alters the Electric field in the wave. Do math problem. 0b01ecef03This paper designed a high-speed differential connector which was separated by air, and use 2D simulation software to analyse the differential pairspsila geometry and the relationship of frequency and differential impedance, and get a good cross-section structure. After each subtraction, re-sort the sequence in non-increasing. What is the effective dielectric constant of a coplanar waveguide? The effective dielectric constant of a CPW depends on the geometry and materials used but is typically in the range of 2 to 5. Rs =. Round Coaxial Cable Calculator. Figure 1(a,b) show the schematics of the two microstrip. 1. Variations on the Waveguide >The double-ridge rectangular waveguide is a type of waveguide used in RF microwave systems. In high-speed transmission circuits, signal integrity is an. 25mm (9. Characteristic. As always, use this information at your own risk. 27mm pinheader impedance. pH nH uH mH H kH. This calculator finds both odd and even transmission line impedance. 3. . Use tricks to increase structure dimensions, use virtual grounds, and use the Si8000m Quick Solver to calculate Zo (diff) values. Characteristic impedance í µí± of strip coplanar waveguide, equivalent. waveguide with dimensions l 2 a. g. where R0 and X0 are the real and. The primary difference between microstrip and stripline configurations is the placement of the signal conductor. When in doubt, use 1 for copper, . This calculator determines the impedance of a symmetric differential stripline pair. There is no one size fits all, but using a 5 thou to 6 thou track width as a starting point helps narrow things down. Calculate Stripline impedance for given PCB parameters. If you use a coplanar waveguide, the copper pours below and on the sides of the conductor must be strongly referenced to each other. The backside of the strip can be made of air or metal (grounded coplanar waveguide). The reason for creating this tool is I failed to find any other (free and open source) alternative. Elliptical Integrals of the First Kind With equations, for solving Elliptic Integrals of the First Kind. The Calculator has the following tools:. If you’re designing an RF PCB for microwave or higher frequencies, controlled impedance routing should be top of. 5mm pitch flat flex as differential coplanar waveguide for routing 1000Base-T ethernet, and I'm using a single ground trace between the differential pairs, sketch attached. To answer, Zac. 3. So the question is, how close do the traces in a differential pair need to be to each other, and is the need for “tight coupling” really Read Article. Thermal Device Calculator . You can use an online coplanar waveguide calculator to play around with your design. Calculator. The return loss in this paper is 20 dB, which is 10 dB higher than the full-wave 3D simulation experiment of transmission line carried out by Peerouz Amleshi . There are several forms of the standard CPW structure, such as. R. How can I compute the differential impedance of an Edge-Coupled Coplanar Waveguide With Ground? I couldn't find any free calculator online, so I wrote a small program which computes the the impeda. This is a 1. After each subtraction, re-sort the sequence in non-increasing. But practically (especially in a dense design like your example), they also interact with surrounding conductors, and the coplanar ground, or ground beneath a differential microstrip will affect the characteristic impedance. 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. All coplanar waveguides come in two varieties: standard coplanar waveguide and grounded coplanar waveguide. Modeling approximation can be used to understand the impedance of. Note: Units do not matter for this calculation as long as they are consistent. Waveguide ports represent a special kind of boundary condition of the calculation domain, enabling the stimulation as well as the absorption of energy. a Cross section of a differential coplanar capacitor, with metal conductors from − ∞ to − b , − a to a , and a to ∞ . Co-planar (also called Coplanar waveguide) track is a type of electrical planar transmission line which can be fabricated using printed circuit board technology, and is used to convey microwave-frequency signals. So the question is, how close do the traces in a differential pair need to be to each other, and is the need for “tight coupling” really Read Article. C = Speed of light. Structure. So, the results are normalized on this reference impedance. Fast Coplanar Waveguide analysis of five of the most popular microstrip structures. If you’re designing an RF PCB for microwave or higher. differential coplanar waveguide calculator. e. Rerun step 5. High-frequency circuit designers must often consider the performance limits, physical dimensions, and even the power levels of a particular design when deciding upon an optimum printed-circuit-board (PCB) material for that design. An equivalent circuit model is given to predict CMN suppression performance of the proposed structure, which is in good. This is the same calculator integrated in other open-source tools like the microwave circuit simulator Qucs, or the circuit board design tool KiCad. 36 mm substrate, has an impedance to ground, unbalanced, of about 49 ohms. Learn how to model structures that are not included in the Si8000m and Si9000e calculators, such as semi-coplanar, offset coplanar strips, and differential surface coplanar waveguide. Coplanar Waveguide Calculator. By 2012, Facebook and Twitter were. but it's probably the fastest solution. EDIT 3: I'm trying to achieve 100 Mbps connections. Therefore, the parallel plate waveguide mode is not established and the problem of spurious resonances is eliminated. The idea here is to determine the spacing required for a given width with the goal of hitting a specific differential impedance value. 946 for silver, or 1. PCB Coplanar Waveguide Calculator RF PCBs can be complex boards that need careful interconnect design and layout. e. Coplanar waveguide - Calculator question. The advantages of coplanar waveguide are that active devices can be mounted on top of the circuit, like on microstrip. Thickness: Thickness of the stripline conductor. Viewed as an edge coupled external plane, Zdiff =148. This. Penirschke y, A. This feature is very useful for measuring balanced circuits with a. While this calculator will provide a baseline, any final design considerations should be made towards loss, dispersion, copper roughness, phase shift, etc. , in x-y plane) is scaled by an amount M(u,v) in the mapped domain (i. 127mm thickness substrate (3. Don’t forget to check out our other. After the simulation, I can normalize this results on a 50 ohm input impedance. To suppress the higher-order modes, a new structure called grounded coplanar waveguides (GCPWs) can be introduced. Users need only specify the material properties for. 84 mils), and space is 0. For a coplanar waveguide, the width required for 50 Ohms impedance on the same substrate is ~20 mils. After optimizing the mathematical model of strip coplanar waveguide, reference plane and differential vias, we built a simulation model of the backplane passive link which met the 100GBASE-KR4. Designing a 50Ω coplanar waveguide on 1. Grounded Differential Coplanar Waveguide Calculator. e. The via spacing is to create a virtual wall the the RF energy. Using coplanar trace, the return current generated by the high frequency signal is shorted to the ground plane. If you’re designing an RF PCB for microwave or higher frequencies. Microstrips and striplines also come in the coplanar and differential varieties, and all of these have certain advantages when used for high-speed or high-frequency signals. Rectangular waveguide is commonly used for the transport of radio frequency signals at frequencies in the SHF band (3–30 GHz) and higher. MAX2605EVKIT. V-shaped conductor backed coplanar waveguide (VGCPW). . microstrip, coplanar waveguide, and optical fiber waveguide. Differential pair routing. Thus a "differential pair" any long distance apart will have an impedance of 98 ohms, without any coupling between the lines, i. Coplanar_Waveguide_Calculator. RF Cafe Forums began sometime around August of 2003 and was quite well-attended for many years. TRL technique involving the on-wafer Vector Network Analyzer (VNA) measurement of differential devices in the frequency band up to 67 GHz. Rectangular waveguide: S. 3. Conductor = metal ( "Gold" ); Design the coplanar waveguide at a frequency of 3 GHz, line length of 0. Enter values for R1 and R2 to calculate attenuator loss and impedance. PCB Coplanar Waveguide Calculator RF PCBs can be complex boards that need careful interconnect design and layout. If you’re designing an RF PCB for microwave or higher frequencies. Square Coaxial Cable Calculator. Stripline Impedance Calculator. • A microstrip or grounded coplanar waveguide PCB will have a quasi-TEM mode • Additionally, there is a change in field distribution and field line length in the signal launch area • The Effective-Dk of the PCB is typically much different than the Dk of the coax. generally the top of a dielectric substrate. A grounded coplanar waveguide is a modified version of FB CBCPWs, in which the coplanar side grounds are connected to the lower ground planes using vias. conductor backed coplanar waveguide (CB-CPW) [2]. Differential Amplifier; Inverting Amplifier; Inverting Comparator with Hysteresis • Schmitt-Trigger;. I've simulated the GCPW (grounded coplanar waveguide) with OpenEMS as well as the miters and blocking cap ground cutouts for a single ended line. 9: Differential coplanar. and one Coplanar Waveguide With Ground Calculator. 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. Otherwise, find a "coplanar waveguide" calculator as it'll compensate for the nearby ground plane. Unexpected low characteristic impedance using the JLCPCB impedance calculator. Calculate Coplanar impedance for given PCB parameters. Use the transmission line objects and functions to create and visualize different types of transmission lines used on a printed circuit board (PCB). c. Dielectric Thickness: mm. For example, if you wish to input "25000000", just type "25M" instead. Substrate Thickness,. A plot of the simulated coplanar impedance vs coplanar gap is shown below. This is common in semiconductors where it is difficult to access a ground plane and the distances are very short. 1. s implemented [l]! and the associated effective dielectric constants based on the full-wave analysis were presented [2]. We offer an affordable online solution to calculate the line impedance on printed circuit boards (PCB). Added coplanar waveguide support for conductor impedance Added degree symbols Fixed F to C conversion for tempriseSo the question is, how close do the traces in a differential pair need to be to each other, and is the need for “tight coupling” really Read Article. See how in your microstrip example the traces are 192 um wide while in the coplanar design they are 117 um wide. This can be set to zero, but the calculated loss will not include conductor losses. Ramo, J. )Higher Skin Effect Losses (Fields Concentrate on Edges of Trace and Grounds). Thickness: Thickness of the microstrip conductor. If you’re designing an RF PCB for microwave or higher frequencies. ”. Posted August 19, 2020. There are also 3 types of differential models – differential, coplanar differential, and coplanar differential without ground. , in u-v plane), where M(u,v) is defined as in eqn. Hi, I'm working on developing a MATLAB script that will calculate the gap between a trace and the surrounding planes in a CPWG. structures is addressed in this Letter. This calculator uses JavaScript and will function in most modern browsers. AppCAD coplanar waveguide calculations - RF Cafe Forums. Coplanar waveguide is a type of electrical planar transmission line which can be fabricated using printed circuit board technology, and is used to convey microwave-frequency signals. This calculator can calculate the impedance and propagation delay of any microstrip by taking its respective height, width, thickness & dielectric constant. 1 Answer. Coplanar waveguide vs stripline. Simply input the required data fields to check your chosen dimensions ensure the. 34mm and gap 0. The Si6000b family of Field Solving Calculators builds on the success of the SI6000A. 6 mm trace width. Access technical papers, white papers, calculators, tools and more for circuit laminates, prepreg and bonding materials. They are also used on single-layer boards that lack a ground plane. Figure 4 shows an example coplanar PCB layout using the LMH1297 bidirectional I/O. This paper based on the theory of transmission lines, according to the coplanar waveguide (CPW) structure, designed a high-speed differential connector which was separated by. coupled coplanar-waveguide structure with- out the central groiind plam was proposed [l]. You can calculate the characteristic impedance of the differential pair using an online calculator, a dedicated transmission line calculator like Polar, or a 2-1/2 or 3-D EM simulator like Ansys or HFSS. Overview. Best regards . 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. When a metal layer is also present underneath the substrate, it is known as a Grounded Coplanar Waveguide. Guide. Figure 8a. 2. All of this includes contributions from coupling. The short version is this: I do not trust the Kicad calculators for CPW & GCPW (FWIW, I’m. 9. 1702mm. Coplanar wave guide with ground plane. Transmission-Line Calculator. Coplanar Waveguide With Ground For Coplanar Waveguide with ground or Microstrip lines with signal side ground plane, showing the formula by Brian C Wadell. 0 of permitivity) at. *PCB vendors can use controlled impedances and will vary any designated trace width at mask level to hit impedance targets. Zhaotong Wan. The cross section of the coplanar waveguide is illustrated in the image above. Coplanar Capacitance. Electro-optic modulators (EOMs) based on a thin-film lithium niobate (TFLN) photonic integration platform play a crucial role in loading electrical signals onto optical signals. Gerth, S. html,v 1. Height: Height of the substrate. This is done to ensure the two pairs maintain consistent differential impedance. and the conductor thickness is thinner than 0. PCB Coplanar Waveguide Calculator RF PCBs can be complex boards that need careful interconnect design and layout. So the question is, how close do the traces in a differential pair need to be to each other, and is the need for “tight coupling” really Read Article. T Attenuator Calculator. If you’re designing an RF PCB for microwave or higher frequencies, controlled impedance routing should be top of mind to. The characteristic impedance (Zo) of coplanar waveguide with ground with signal side ground plane can be calculated using the active calculator below. This can be advantageous, especially when making connections at high frequencies. Figure 3 (right) illustrates the resulting graphs. e. For example, CPW was proposed by Wen in 1969 [1], [2]. coplanar waveguide calculator hi all, I need the equations to calculate the width,the gab and the effective dielectric constant for CPW. One routing structure, called a substrate integrated waveguide, provides a useful alternative that is ideal for engineering the electromagnetic field along an. Choose a routing style (microstrip, stripline, coplanar waveguide, single-ended vs differential) Calculate the trace width needed to give the required impedance; After everything is routed, it’s now a question of whether it’s appropriate to fill in the unused regions of the surface and internal layers with the grounded copper pour. Remove the first element (largest degree) from the sequence and call it “d. <P>The coplanar stripline (CPS) consists of a dielectric substrate with two parallel strip conductors separated by a narrow gap. i know that i can use. This parameter is used for the loss calculations. Radio Frequency Engineering Calculator. In this article we present the dispersion characteristics as well as frequency-dependent field configuration and characteristic impedance for edge-coupled, shielded, coplanar waveguide structures. Coplanar Waveguide formula: ? TransCalc is an open-source impedance calculator of various transmission lines based on common closed-form approximations. There exist two main types of coplanar lines: the first, called coplanar waveguide (CPW), that we will study here, is composed of a median metallic. PCB Coplanar Waveguide Calculator RF PCBs can be complex boards that need careful interconnect. In this paper, the methods used to analyze FGC, FGC waveguide propagation characteristics, and how FGC may be. *Solder resist PCB coating will have the effect of lowering the impedance (due to the 30um or so of Er 3. High-frequency circuit designers must often consider the performance limits, physical dimensions, and even the power levels of a particular design when deciding upon an optimum printed-circuit-board (PCB) material for that design. This kind of port simulates an infinitely long waveguide. Figure 1 - 3D model of the transition from microstrip line to CPW (a) top view of the model, (b) bottom view of the model. To further reduce the trace width, you can go for a "differential coplanar waveguide with ground" topology. A novel edge-coupled coplanar-waveguide (CPW) structure with finite-extent backed conductor is proposed. Trace Width, W. High-speed designs carry a requirement for controlled impedance, crosstalk control, and the need for interplane capacitance. Unfortunately, TxLine doesn't do coplanar waveguide for differential traces. 4 Conventional Coplanar Waveguide on a Finite Thickness Dielectric Substrate and with a Top Metal Cover 21 2. Rectangular. In effect, the role of a differential pair impedance calculator is to calculate one of the odd-mode or differential impedances, and then use this to calculate the other while assuming the two ends of the pair obey specific. Online calculator - Conductor-backed edge coupled coplanar waveguide. A grounded coplanar waveguide is a modified version of FB CBCPWs, in which the coplanar side grounds are connected to the lower ground planes using vias. The impedance is determined by the ratio of trace width to clearance, so size reduction is possible without limit, the only penalty being higher losses. Aug 30, 2010 #1 T. Microstrip lines, coplanar waveguides. A rectangular waveguide is a conducting cylinder of rectangular cross section used to guide the propagation of waves. In a coplanar waveguide, a center conductor with ground stitches on both sides of the signal is used. More importantly, it can provide extremely high frequency response (100 GHz or more) since connecting to CPW does not entail any parasitic discontinuities in the ground plane. Spacing and width value pairs that will give a differential impedance of 100 Ohms on Dk = 4. This exercise will be left to the user. To avoid microstrip modes, have h >> (w+2g) and extend component side ground away from the trace by > (w+2g). To avoid microstrip modes, have h >> (w+2g) and extend component side ground away from the trace by > (w+2g). The Si8000m assumes negligible insertion loss in the transmission line; should you wish to model insertion loss the Si9000e adds. Radio Frequency Engineering Calculator. Grounded Differential Coplanar Wave Guide. This is the same calculator integrated in other open-source tools like the microwave circuit simulator Qucs, or the circuit board design tool KiCad. A plot of the simulated coplanar impedance vs coplanar gap is shown below. A differential length in real space (i. e. This trick works just as well for differential traces too, although Altium seems to keep using the minimum spacing whatever the trace width. TX-LINE software is a FREE and interactive transmission-line utility for the analysis and synthesis of transmission-line structures that can be used directly in Cadence ® AWR ® Microwave Office ® software for matching-circuits, couplers, and other high-frequency designs. coplanar waveguide calculator — Coplanar Waveguide Calculator. But what it does, it does well, which is to calculate key parameters for most common microwave transmission lines, including microstrip, stripline, and coplanar-waveguide transmission lines. Coplanar waveguide (CPW) (Figure (PageIndex{1})(b)) [1] supports a quasi-TEM mode of propagation with the active metallization and the ground planes on the same side of the substrate. Width (W) in micrometers: Gap (G) in micrometers: Height (H) in micrometers: Substrate Height (Hs). 1 © 2016 ANSYS, Inc. Modeling approximation can be used to design the microstrip trace. • Microstrip: A strip conductor on top of a dielectric substrate with a ground plane beneath the substrate. There are three calculators for Microstrip including the Microstrip Transmission Line Characteristic Impedance Calculator Using an equation by Brian C Wadell. The following formula is used to calculate the cut-off frequency, lower & higher operational frequency of the rectangular waveguide. 8065. fletcher Member level 3. I wouldn't bother recalculating, leaving it as is and having the clearance is. Fourteen new coplanar differential models have grown the library to 39 structures at introduction, with more to come. List of our impedance calculators Following is the table of 82 impedance calculators that are designed and categorized based on the different trace geometries: 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. Gupta in [3] lists various types of CPW: CPW with finite dielectric thickness, CPW with finite width ground planes, CPW with a cover shield, conductor-backed CPW with a cover shield, conductor-backed CPW, multilayered CPW, asymmetric CPW and asymmetric CPW. For this case the capacitance per unit length of the line is given by analytic results [1] C(cp,a)/L =4ǫK(κ)/K(p 1−κ2) (11) ≃ (4ǫ/π)ln[2(1+ √ κ. 87 mils). Grounded Coplanar Wave Guide. After optimizing the mathematical model of strip coplanar waveguide, reference plane and differential vias, we built a simulation model of the backplane passive link which met the 100GBASE-KR4. f 2 = Upper operational frequency in GHz. T Attenuator Calculator. If you recall my earlier article on microstrip vs. The STLC online tool enables the user to precisely calculate the wave impedance of all commonly used transmission line types on PCBs by applying a powerful 2-D field solver technology. 6mm FR4. All transmission line structures, such as microstrip, stripline, or CPW. To download this add-on:. To address the excitation and. 946 for silver, or 1. Waveguide impedance can be calculated using the formula: Z = (377 ohms) / sqrt (1 – (fc/f)^2), where Z is the impedance, fc is the cutoff frequency, and f is the. Grounded Differential Coplanar Wave Guide. 全面に形成された導体箔に線状の空隙部を設け、その空隙部の中央に線状の導体箔を形成した構成. The lower ground can be used for heat sinking purposes while providing mechanical support and preventing the fields from coupling to interconnects on lower circuit layers [3], [4]. In. Vilcins-Czvitkovits, D. Rho: Conductor resistivity relative to copper. Differential Coplanar Waveguide; Differential. The KiCad PCB Calculator is a set of utilities to help you find the values of components or other parameters of a layout. The differences between the two structures can be seen in the illustration below. Cohn). If eq. For example, rfckt. Where, f c = Cut-off frequency of rectangular waveguide in GHz. For example, a single 0. You're looking for a differential coplanar waveguide calculator. PCB Coplanar Waveguide Calculator RF PCBs can be complex boards that need careful. I have attached a model of a CPW. A method to change the through-hole structure to widen the GCPW is investigated in this paper. You can calculate the characteristic impedance of the differential pair using an online calculator, a dedicated transmission line calculator like Polar, or a 2-1/2 or 3-D EM simulator like Ansys or HFSS. The Field Solvers in the Si6000b allow you to accurately graph impedance against various PCB parameters. The same limitations for S and G apply in this topology as for the grounded coplanar. Note that the y-axis is on a logarithmic scale for clarity. Apply the Havel-Hakimi algorithm by iteratively performing the following steps: a. Jakoby Institut f ur Mikrowellentechnik und Photonik, TU Darmstadt, Germany¨ C. , on top of a 2-layer of a PCB with no internal ground). 29mm, on the 0. 5,Z0=75); show (txem) Coplanar Waveguide (CPW) In a coplanar waveguide (CPW) structure, metalization is present only on top of a dielectric slab. Right: The boundary selection of the coaxial lumped port in a 2D axisymmetric model. Figure 1. Calculate Microstrip impedance for given PCB parameters. The Calculator has the following tools:. In the case of this article, it can also be considered the condition for the absence of parasitic modes in a waveguide of cross-section a 2 H or l 2 H. 45 for gold. Hi folks I’ve just emerged from a rabbit hole & thought I’d share what I learned regarding available impedance calculators for coplanar waveguide (CPW) and coplanar waveguide w/GND (GCPW). The microstrip is a very simple yet useful way to create a transmission line with a PCB. Jun 22, 2016 at 5:29. If you run ground pour right next to the analog traces, you’ve just created a coplanar waveguide, which has high isolation and is a common choice for routing high-frequency analog signals. Commonly fabricated with printed circuit board (PCB) technology, a microstrip antenna calculator tool is an electrical transmission line that is. Coplanar waveguide with stitching vias. Stripline. Differential Coplanar Waveguide Calculator. Microstrip Calculator. The iCD Design Integrity software incorporates the iCD Stackup Planner, iCD PDN Planner, iCD CPW Planner and SmartSolver software plus a myriad of functionality specifically developed for high-speed PCB design. Coplanar Waveguide With Ground For Coplanar Waveguide with ground or Microstrip lines with signal side ground plane, showing the formula by Brian C Wadell. Choose a routing style (microstrip, stripline, coplanar waveguide, single-ended vs differential) Calculate the trace width needed to give the required impedance; After everything is routed, it’s now a question of whether it’s appropriate to fill in the unused regions of the surface and internal layers with the grounded copper pour. Embedded microstrips are commonly crafted using printed circuit boards, although other. we have placed the Die Per Wafer calculator as an online Excel sheet so you. Relative Dielectric Constant ( εr ): Track Width: mm. This effect can impact vision comfort and binocular vision. Balanced transmission line with two center conductors. Coplanar waveguide for differential trace calculator. Our free impedance calculator for coplanar waveguide can help you with your design features to ensure your PCB is working as you intend. Alternatively, Generate R1 and R2 for a wanted attenuation. Waveguide ports represent a special kind of boundary condition of the calculation domain, enabling the stimulation as well as the absorption of energy. Ideally the traces in the differential pair only interact with each other, as another answer said. *The structure may propagate in 3 modes: coplanar waveguide, coupled slot lines and microstrip. For the 70. It signifies the variation in how light is bent as it passes through different parts of the lens. , in u-v plane), where M(u,v) is defined as in eqn. The key to answering this question requires looking at the S-parameters for a grounded coplanar waveguide (GCPW). b. This configuration of the CPW is known as the conductor-backed coplanar waveguide. Our free impedance calculator for coplanar waveguide can help you with your design features to ensure your PCB is a working printed circuit board.