Preferred resistor values are entered into the text boxes, similar to the way that values for a prototype may be selected. The Insertion Loss formula is defined as the loss of signal power resulting from the insertion of a device in a transmission line or optical fiber and is usually expressed in decibels (dB) and is represented as I L = 20* log10 (V t / V in) or Insertion Loss = 20* log10 (Voltage / Input Signal Amplitude). p65 Author: barbara Created Date:Return Loss is the portion of a signal that is lost due to a reflection of power at a line discontinuity. A network analyzer can be used to make S parameter measurements. A SWR can be also defined as the ratio of the maximum amplitude to. voltage standing wave ratio. 1) VSWR Calculation. Return Loss VSWR Reflection. Introduction to VSWR. In an RF system, when power is sent from the source to load, there are three main parameters to be considered: (1) incident power; (2) reflected power; and (3) power absorbed by the load. The return loss & VSWR is related by the following formula, from which we can calculate return loss for a given VSWR. 5-1-0. A commonly required conversion is between return loss and VSWR, and some values are tabulated in chart, along with a graph of these values for quick reference. VSWR specs (specifications) are introduced, along with formulas for mismatch loss and return loss in relationship to VSWR. In order to improve the VSWR, this calculator also has an extra input for adding an attenuator to improve or reduce the system VSWR. Using complex impedance is an important technique for handling multi-component AC circuits. Values for L and C will be calculated for the four topologies shown. RF calculations and conversions include metric-standard, link. This can be built into a FLEXI-BOX and a transmission line PCB is available which easily adapts for this circuit with one simple trimming operation. 405 inch. Noise Conversion Calculator. Free Space Path Loss Calculator Calculate the loss for a given distance at an RF frequency Enter distance in km and frequency in either MHz or GHz. S21 is the transmission coefficient of Port 2. Measurement and control of gain and reflected power in wireless transmitters are critical auxiliary functions that are often overlooked. Thus with ~ 25% reflected power: Return Loss = -10 x Log [ 100/25. To use the calculator, enter the VSWR value for each of the assembly components being added, as exampled below. 97dB. While return loss analysis can be an ambiguous quality indicator,. 29:1 VSWR Is this correct? If so, performing the same analysis in the reverse order (with respect to the power meter), gives me: RL for the system (wrt to the power meter) = 19. Recall that signs of reactances are missing on the full chart. What is the VSWR ratio to return loss? There is an inverse relationship between Voltage Standing Wave Ratio (VSWR) and Return Loss. Wavelength dBm dBuV W dBuVm mWcm2 pJcm2 V VSWR This RF calculator has been developed by Compliance Engineering as a resource for individuals. We have designed a special VSWR and Return Loss Calculator. Convert the VSWR value to a ratio by subtracting 1 from the VSWR value. transmitter) with the load (i. This online reflection coefficient to VSWR calculator calculates the VSWR by entering the reflection efficient Γ (= value between 0 & 1). Useful converters and calculatorsVSWR & Return Loss Calculator: Enter forward and reflected power or match to determine equivalent values. See the relationship between VSWR and return loss. This is an online calculator that calculates Return Loss based on Reflection Coefficient. Return loss, also known as reflection loss, is a measure of the fraction of power that is not delivered by a source to a load. Fiber calculators and tools. Measurement and control of gain and reflected power in wireless transmitters are critical auxiliary functions that are often overlooked. Measuring Insertion Loss using RETURN LOSS MODE. It converts the following units: • VSWR • Reflection • Return Loss • Prefl (Power reflection) • Reflections, Reflectionl to Mismatch Uncertainty Enter a value in any field, and all the other values are calculated and displayed. Let’s start by looking at a 2-port device illustrated in Figure 1. VSWR to Return Loss (dB) Calculator. 특히 Return loss와 VSWR의 대략적 값의 관계정도는 암기해두는게 편리할 때가 많다. Our RF calculators and converters will provide the figures you need for your radio frequency engineering needs. Vswr To Rl Formula. It is due to inherent imbalances in directional devices. transmitter) with the load (i. Suitable for VHF (~1. g. This is because the parasitics of lumped elements tend to kill the frequency response as you go higher in frequency. Calculate VSWR, Return Loss, etc. VSWR to Return Loss Conversion Table. Suitable for higher power (~1800 watts) at HF. VSWR (Voltage Standing Wave Ratio) = [1+Sqrt (Pr / Pf)] / [1-Sqrt (Pr / Pf)] Pf = Forward Power (Watts); Pr = Reflected Power. 3. Clear. Learn about voltage standing wave ratio (VSWR), return loss, and mismatch loss, which helps characterize the wave reflections in a radio frequency (RF) design. VSWR/Return Loss Frequency Band VSWR Return Loss (dB) 680–800 MHz 1. The relationship between composite return loss and individual return loss in the constructive condition of identical mismatches is that the composite VSWR is the the square of the individual VSWRs. 1, directivity does not depend on the distance from the antenna. RL = 20 * log10 ( (VSWR + 1) /. You can also use LTSpice to calculate S-parameters as well, which is a bit of a hidden trick. Suppose the wave is not matched with load and signal there is some unwanted signals are interrupted or signal loss is occurred. The return loss and VSWR measurements are key measurements for anyone making cable and antenna measurements in the field. Pasternack's VSWR/Return Loss Calculator finds VSWR, Return Loss, Mismatch Loss, and the Reflection Coefficient given any one of the listed input types. This online reflection coefficient to VSWR calculator calculates the VSWR by entering the reflection efficient Γ (= value between 0 & 1). S11 then would be the reflected power radio 1 is trying to deliver to antenna 1. The Smith Chart Pegasus Technologies. 19. The following variables can be changed in this tool: - Load VSWR. Note: The historical definition of return loss results in a negative sign. For support with the MatchCalc tool, contact tool-feedback@qorvo. The main cause of the mismatch is the deviation in the con-Resonant Frequency Calculator. ,100 % power transferred from a source to a load via a transmission line/cable). 12] = 6 dB. Given a return loss (variable = RL ) in dB, the VSWR is calculated as follows: The magnitude of the reflection coefficient is defined as Rho , where Rho = ( 10 ^ (RL/-20)): e. Return Loss. Pasternack's RF Calculators and Conversions section provides engineers valuable and easy-to-use tools ranging from complex mathematical formulas to simple conversions. These calculators help with unit conversions, VSWR calculations, attenuator design, antenna design, radars, and various other basic calculations that are often required. Unless you have a piece of slotted line-test equipment this is a hard definition to use, especially since the concept of voltage. The view of any reflected voltage wave alone so see the reactive part would need the reflected current to plot the ratio, so it is not used. These are the standard set of equations for converting between VSWR, return loss, and reflection coefficient (Γ). VSWR measures the ratio of voltage peaks and valleys. Advanced Control Components. VSWR is commonly expressed as a ratio. Subscribe to receive Mini-Circuits News. It is often expressed in terms of a percentage, or in dB. 259 0. VSWR Mismatch Errors: Both amplitude and phase errors are introduced when mismatched impedances are present at an electrical interface. VSWR ( VSWR meaning Voltage Standing Wave Ratio) is an important concept in radio frequency (RF) engineering. 12 VSWR max. Lower VSWR means lower reflection power (good impedance matching); thus, power transfers to load will be high. The corresponding value in the right column is the return loss value. applied power and return loss of load, measured at 1 GHz. VSWR = Voltage standing wave ratioThis calculator uses the following formulas for converting the values between the VSWR, return loss, reflection coefficient, and mismatch loss. This antenna tilt angle calculator also provides,. S21 is the transmission coefficient of Port 2. The field calculator is a very powerful but frequently The following pages contain calculator routines, or “recipes”, for use within the Field Calculator misunderstood and underutilized tool within the 3D “Fields” Post-Processor. **Note: All of our calculators allow SI prefix input. 34:1 or a return loss of 16. 64% or ±10 x log10 (103. Therefore, a VSWR of less than 1. 4. Forward Power vs Return Loss Calculator RF calculators and converters. On the other hand, VSWR and the reflection coefficient are connected by the equation: VSWR = (1+|Γ. 8. VSWR Calculator: This is the ratio of maximum voltage to minimum voltage in standing wave pattern. A Forward and Reflected Power to VSWR Calculator is a tool that helps to determine the Voltage Standing Wave Ratio (VSWR) of a transmission line by using measurements of the forward and reflected power. 695. So a perfect match can be represented by the range 0. Here's a simple VSWR calculator. 09 = 1. You can access the RF Path Calculator at the Calculators page of our website. Vswr To Rl Formula. 50:1, the resulting maximum VSWR will be 4. The load ZL imposes an additional constraint on the relationship of the total voltage and current at z = 0: VL IL = V(z = 0) I(z = 0) = ZL. As an added bonus, the results are modifiable and can calculate. Next, plug in the calculated return loss value into the formula VSWR = (1 + 10^ (RL/20))/ (1 - 10^ (RL/20)). 14 dB per hundred feet. VSWR can be generated by Network Analysers. VSWR / Return Loss Calculator. In some cases, users require a custom impedance value. Enter the source characteristic impedance and the load impedance then press "Calculate" below. Matching Pi Attenuator Calculator. Enter VSWR, Reflection Coefficient, or Return Loss to calculate remaining values. Formulas used: s r r. The new calculator remains Excel-based; however, provides an enhanced interface so users can: Add radio/tester as a component as it impacts some calculation. 1) VSWR. You can use it for free. , bn). Pout is the output power or signal level. By entering the values given above into the VSWR calculator, we see that the probable assembly-chain VSWR of: 1. 41:1 with a return loss of 15. Forward Power (dBm)Skin depth calculator Stripline Impedance calculator Smith charts VSWR/Return loss converter Wavelength calculator Wilkinson splitter designer. A high. This is an online calculator that calculates Return Loss based on VSWR. Return loss is the measure of how small the “return” or reflection/echo is. $\begingroup$ If that was the only information you were given, you would first find the return loss looking at the load, then use system 2's S matrix to find the RL looking into it, then do the same with system 1 until you finally have the RL looking into the entire network. For S 11 it is also possible to display return loss and (voltage) standing wave ratio [(V)SWR] over frequency range. In this Inside Wireless episode we will look at Voltage Standing Wave Ratio (VSWR), |S11|, and Return Loss. This collection of RF and Power Management design tools reflects Qorvo's commitment to the engineering community. A power sensor with a return loss of –23 dB is connected to a calibration source with a return loss of –20 dB. It turns out that -13. VSWR is the voltage standing wave ratio it used to measure the all-types waves (example: antenna waves) during transmission. Unwrapped phase and reference plane extensions. VSWR - Return Loss - Γ Conversions These are the standard set of equations for converting between VSWR, return loss, and reflection coefficient (Γ). If a complex plane is used with resistance along the real axis then the reactances of the capacitor and inductor are treated as imaginary numbers. 5dB loss per 100 feet at 146 MHz). The reader is encouraged to do this with the full impedance Smith chart as shown in Figure 3. Linkedin. Calculate the VSWR in another column. This is equivalent to VSWR 5. VSWR: RL (dB) 1. Enter VSWR (a value greater than or equal to 1) S11 to VSWR Formula S11 = (VSWR-1)/ (VSWR+1) S11 (dB) = 20*Log10 (S11) The input reflection coefficient, S11 < 1 Example Calculation For a VSWR of 1. Antenna). cdn-anritsu. number) VSWR or % Reflected Power: MHz: a wavelength in inches or feet: Get Help. If there is something in the microwave universe that you need a different calculator for, drop us a note and we'll see what we. The Tee attenuator (T-pad) is a specific type of attenuator circuit which resembles the shape of the letter "T". 0 indicates about 75% of the power is delivered to the antenna (1. reflected energy. 41:1 with a return loss of 15. The formula and equations used by this calculator are also provided. Just enter the value of source return loss, input return loss, output return loss, load return loss, device gain, and isolation then the calculator will compute the minimum and maximum gain. The equivalent VSWR is 1. R = 10log 10 (P incident /P reflected) and. The table below converts between VSWR, return loss, reflection coefficient, mismatch loss, reflected power and through power. Cable and antenna analyzers allow operators to measure return loss/VSWR, cable loss, distance-to-fault (DTF) measurements, reflection measurement, antenna isolation measurement, impedance, etc. Select operating frequency. 8. e. (1) ea Flex Assy - 1. return loss Calculator (by using VSWR) Skin. 098Ω resistor in parallel with a 306. 3 dB. , an), the wavestravelling away from the n-port are b = (b1, b2,. 1 Return Loss. (1) ea Flex Assy - 1. Return Loss vs VSWR Calculator: The calculator calculates VSWR from return loss and return loss from VSWR. 5 0 0. Stripline Impedance calculator Smith charts VSWR/Return loss converter Wavelength calculator Wilkinson splitter designer. Since directivity is a ratio of power densities, it is unitless. 0001, J2)". Individual calibration is generally recommended to account for manufacturing process variation. The Insertion Loss formula is defined as the loss of signal power resulting from the insertion of a device in a transmission line or optical fiber and is usually expressed in decibels (dB) and is represented as I L = 20* log10 (V t / V in) or Insertion Loss = 20* log10 (Voltage / Input Signal Amplitude). I have already calculated the cascaded VSWR and RL using the RSS method (very similar result to simply multiplying each components VSWR as Itay mentioned), but the problem is that the result is not even close to the measured value of return loss. In Figure 14, the ADL5920 is being used to measure the return loss of the load, also at 1 GHz. 44 . The ratio of a sinusoidal signal reflected back from the load to the incident signal is called return loss. Note: VSWR values were used to calculate the other two related values (rounded to 3 significant places). 특히 Return loss와 VSWR의 대략적 값의 관계정도는 암기해두는게 편리할 때가 많다. The VSWR value range from 1. Title: dg03-110. VRMSF and VRMSR are measured and the return loss is back calculated. Thus, RL for the system (wrt to the input port) = 17. In addition, the calculation takes into account the effect of signal attenuation in the transmission line. As an added bonus, the results are modifiable and can calculate the other values. Mismatch Loss (dB) 3. These are two different ways to measure the same thing. For example, a VSWR of 1. In one typical RF application, VSWR is. Directivity and VSWR Measurements. **Note: All of our calculators allow SI prefix input. dl. Example 2. 5 GHz 16-way Power Divider DC-3 GHz 8-way Power DividerA series of RF calculators for radio frequency engineers. Return loss = 10 log (Pr / Pi) = 20 log (Er / Ei) For example, if a load has a return loss of -10 dB, then 1/10 of the incident power is reflected. Lower VSWR is always desirable for a system. 5:1. This calculator allows you to calculate the input impedance of a transmission line, as well as the VSWR, return loss, and mismatch loss at the input point. In summary, return loss is the loss of signal power due to signal reflection or return by a discontinuity in a fiber-optic link or transmission line. The calculated value is MUCH worse. 1. The Smith Chart graphically maps S11=reflection coefficient= (ZL-Z0)/ (ZL+Z0) to Load Impedance (ZL), normalized to Z0 (source impedance = center of chart). Reflections propagate back and forth in a line, but most assessments only consider the effects of the initial reflection because the back and forth energy attenuates until it is untraceable. Thus with ~ 25% reflected power: Return Loss = -10 x Log [ 100/25. SWR Excel SheetMeasured VSWR = ratio: RL dB: VSWR at antenna = ratio: RL dB: Power into/at antenna = watts: Power reflected from/at antenna = watts: Notes: Maximum Power rating for RG213 cable is 250 watts taking into account environmental de-rating. VSWR Mismatch Errors: Both amplitude and phase errors are introduced when mismatched impedances are present at an electrical interface. Equations $$VSWR = \frac{1 + \Gamma}{1 - \Gamma}$$ $$\Gamma = \frac{VSWR-1}{VSWR+1}$$ $$L_{R} = -20log_{10}\Gamma$$ Hence, the return loss is always lower than the ideal system (i. 05 + 1. 93 dB. In order to get the best power transfer from a source to a load, the source impedance must equal the complex conjugate of the load impedance: Rs + jXs =RL −. VSWR. Finally, an antenna VSWR monitoring system is shown. Measured forward power vs. When you look at a graph of a return loss formula, the negative sign is often omitted and is sometimes used interchangeably with the S11 parameter. If the antenna reflects 250 watts the VSWR at the antenna will be 1. 7. 7. 34:1 or a return loss of 16. 1. For example, an efficiency of 0. Directivity, on the other hand, is the level of the signal which appears at Port 4 and is undesired. Cable impedance ohm. Now, let us investigate the physical meaning of return loss. VSWR calculator: Isolation between circuit stages (mentioned above) is a way to minimize the voltage standing wave ratio (VSWR) and, in this way, improve impedance matching. 0. Here's the unwrapped phase of S21:by Eamon Nash Download PDF. You can use our VSWR calculator to see that 1. 8ghz. It turns out that -13. This can be built into a FLEXI-BOX and a transmission line (50 Ohm track) PCB is available which easily adapts for this circuit with one simple trimming. Step 1. A ratio of 2:1 indicates that reflections have. 표현할 때는 VSWR 값을 어떤 비율값처럼 표현하는데, 예를 들어 아래수식에 의해 VSWR이 3으로 계산되는 경우는 VSWR이 3 : 1 이다 라는 식으로 표현한다. 333, a mismatch loss of 0. Understanding VSWR and Return Loss. VSWR Calculator. 600mW. e. Reflection Calculator. Requires Windows 7 (64 Bit) or higher. You can use our VSWR calculator to see that 1. Clear. 16-Feb-2022. to a calculator or computer program that will handle it. These equations can be solved with a personal computer and suitable software, or the parameters may be determined with the Smith Chart. To convert from Return Loss to VSWR, find the return loss value in the left column. 5:1 VSWR is equivalent to -13. . 3 Attenuation Frequency (MHz) Attenuation (dB/100 m) Attenuation (dB/100 ft) Average Power (kW) 1. So Return Loss is positive quantity RL (dB)= Incident power ( Pi)/Reflected power (Pr. T Attenuator Calculator. —and calculates both the typical system return loss along with the worst case return loss. 707. Note that in general S-parameters are a function of frequency (i. This calculator converts between return loss (RL), voltage standing wave ration (VSWR), and reflection coefficient (Γ). VSWR = Voltage standing wave ratio. At 1000 MHz, the S11 (dB) = -RL (dB) = -15 dB. This mix of web-based tools and downloadable Windows software was developed to help engineers design faster and more accurately. 50 from 6 votes. The load can be an antenna, filter or other equipment connected to a transmission line. The return loss is the ratio of the power of the. To convert from VSWR to Return Loss, find the VSWR value in the left column. The ratio of a sinusoidal signal reflected back from the load to the incident signal is called return loss. When a transmitted wave hits a boundary such as the one between the lossless transmission line and load (Figure 1), some energy will be transmitted to the. Home. Click here to use the VSWR. The following formula is used to calculate the Return Loss (RL) from Voltage Standing Wave Ratio (VSWR). This calculator computes the VSWR, reflection coefficient, return loss and matching loss in a transmission line. LOSS VSWR LOSS VSWR LOSS VSWR LOSS VSWR LOSS VSWR (dB) (dB) (dB) (dB) (dB) return loss Vs. 25mW. To use this calculator, enter one of the following data: the voltage standing waves ratio VSWR, the return loss RL, the reflection coefficient ρ, the power ratio ρ 2, the forward and reflected power P fwd and P ref; or the impedances Z c and Z l. Qorvo MatchCalc is a downloadable RF matching calculator designed to provide ideal component values for matching the impedance of a S1P or S2P file to a desired system or reference impedance. 92 dB 0. So a perfect match can be represented by the range 0. Calculates the resistor values, attenuation, minimum attenuation, 'impedance', reflection coefficient, VSWR and return loss of a matching Pi attenuator. Step 3. This calculator converts between return loss (RL), voltage standing wave ration (VSWR), and reflection coefficient (Γ). (also called insertion loss). The input to the antenna will be 8,511 watts. **Note: Like our stripline impedance calculator, all of our RF calculators allow SI prefix input. 985 dB ==> 1. number) VSWR or % Reflected Power: MHz: a wavelength in inches or feet: Get Help. voltage standing wave ratio 020710. net I(RL) V1. The input to the antenna will be 8,511 watts. The concept behind the Smith Chart is simple. Calculate VSWR, Return Loss, etc. Calculate SWR and return loss from impedance values. This can be built into a FLEXI-BOX and a transmission line PCB is available which easily adapts for this circuit with a simple trimming operation. voltage standing wave ratio. VSWR table of return loss vs. S11 is the reflection. Figure 14. This can be built into a FLEXI-BOX and a transmission line PCB is available which easily adapts for this circuit with one simple trimming operation. 064 36. These parameters are often applied to antennas, RF filters and RF amplifiers such as LNA s and PA s. VSWR Mismatch Errors: Both amplitude and phase errors are introduced when mismatched impedances are present at an electrical interface. The low-pass filter often is a natural choice for lumped element filters. 5 10. ANSOFT CORPORATION HFSS FIELD CALCULATOR COOKBOOK INTRODUCTION feature of Ansoft’s HFSS Version 7. 672 0. For support with the MatchCalc tool, contact [email protected] 24. This calculator converts values between VSWR, Return loss, Reflection Coefficient and Mis-Match Loss. 09 = 1. Because the reflection coefficient Γ < 1, then the return loss will have a positive dB value. Calculates the absolute load impedance, reflection coefficient, VSWR, return loss and mismatch loss of a load. Click here to use the VSWR Calculator . ERP, Line Loss and Various Calculators, Antenna Voltage and Current and Feedline Voltage and Current. and Canada (866) 727-8376 International +1 (949) 261-1920Installer for the Windows version of dB Calculator. Return Loss or a VSWR: return loss (dB) (evaluated as neg. 1. flectioncoefficientΓ,voltagestandingwaveratio(VSWR) and return loss (RL) and these quantities are interre-lated. Low-pass lumped element filters. 000:Calculate SWR and return loss from impedance values. USA CHINA MALAYSIA INDIA ISRAEL UNITED KINGDOM. It also shows the percentage of forward to reflected power. The below step by step solved example problem may helpful for users to understand how the input values are being used in such calculations to find the ratio of load impedance matching to the transmission line or wave guide characteristic impedance (Z 0). To use this calculator, enter one of the following data: the voltage standing waves ratio VSWR, the return loss RL, the reflection coefficient ρ, the power ratio ρ 2, the forward and reflected power P fwd and P ref; or the impedances Z c and Z l. Convert VSWR to Return Loss and vice versa. VSWR is the ratio of the peak amplitude of a standing wave to the minimum amplitude of a standing wave, as seen in the following Figure: Figure 1. Return Loss (dB) VSWR. Milli Watts to dBm Calculator. RL OUT = 20log10|S 22 | dB This calculator computes the VSWR, reflection coefficient, return loss and matching loss in a transmission line. 0 0. Consumers; Contact Us;A network analyzer can be used to make S parameter measurements. Example Problem Find the SWR of the transmission line or wave guide whose load or. Voltage standing wave ratio (VSWR), or often given as just standing wave ratio (SWR), is the ratio between the transmitted and reflected voltage standing waves at a signal chain element incident node. To convert from VSWR to Return Loss, find the VSWR value in the left column. Pout is the output power or signal level. In addition, the calculation takes into account the effect of signal attenuation in the transmission line. Fill in the input field and select the input type and click the "calculate" button to show the values. Figure 1. Load serial resistance and reactance ohm. 예를 들어 Return loss가 10dB 정도라면, VSWR은 2:1 이하가 되어서 입력매칭이 비교적 잘된 경우로 평가하며, Return loss가 14 dB 정도가. 5 0 0. e. A VSWR of 6 or more is pretty high and will generally need to be improved. Power (dBm) = 10 x Log [ Power (Watts) ] + 30 dB. applied power and return loss of load, measured at 1 GHz. 8. 예를 들어 Return loss가 10dB 정도라면, VSWR은 2:1 이하가 되어서 입력매칭이 비교적 잘된 경우로 평가하며, Return loss가 14 dB 정도가 되면 VSWR은 1. There is also a selection of suitable RF. 5. In industry, VSWR is sometimes pronounced "viz-wer". Where, RL = Return loss in dB. The VSWR is an important measure of the quality of a radio antenna system. 1. Antenna). What is the VSWR ratio to return loss? There is an inverse relationship between Voltage Standing Wave Ratio (VSWR) and Return Loss. As an added bonus, the results are modifiable and can calculate the other values. Even if a computerYoni Calculator Online Test System Configurator ezSample. How to Use? Using the VSWR to RL Calculator involves the following steps: Enter VSWR Value: Input the VSWR value that you want to convert into RL. comThe antenna accepts a certain amount of energy delivered to it by the transmission line (characterized by S11, VSWR, or return loss), and Antenna Efficiency characterizes the amount of energy lost ‘in’ the antenna after this. This VSWR calculator will calculate return loss, mismatch loss, loss in percentage and the reflection coefficient. Fill in the input field and select the input type and click the "calculate" button to show the values. The corresponding value in the right column is the return loss value. Note: If you select a waveguide size from the dropdown below, the broad wall width will be automatically calculated along with the other results. Low-pass lumped element filters. Specifically, return loss is related to the reflection coefficient (Γ) as follows: Return Loss (dB) = -20 log10|Γ|. The voltage standing wave ratio (VSWR) is defined. It's assumed that the source impedance is also complex. In the above. Free Online Engineering Calculator to quickly convert a Return Loss (dB) into a VSWR. Formally, S11 is the negative of return loss and. Simply select the quantity of convergence points, adjust the length and select the cable from the menu to create a bill of materials will be generated - showing the minimum amount of items required to configure a system.