Stage: NF (dB) Gain (dB)The voltage standing wave ratio (VSWR) is defined. Subscribe to receive Mini-Circuits News. This antenna tilt angle calculator also provides,. And S12 is the power from radio 2 that is delivered through. Wavelength. VSWR & Return Loss Calculator Enter forward and reflected power or match to determine equivalent values. e. Các ứng dụng của VSWR: Các chức năng chính của VSWR : Truyền Antenna: Tỷ lệ sóng đứng điện áp (VSWR) là một chỉ báo về lượng không phù hợp giữa một ante nna và đường cấp dữ liệu kết nối với nó. VSWR (pronounced "viswar"), or the Voltage Standing Wave Ratio, is the ratio of the maximum standing wave amplitude at one node to the minimum amplitude at another node in a system. This calculator is designed to be an informational and educational tool. A return loss conversion table is used to quickly convert VSWR values into return loss values. This calculator is designed to model the common configuration where a transmitter which is designed for a particular load impedance, is connected to a an antenna of that impedance, over transmission line of the same. This table is particularly useful when designing antenna systems. Reflection -3dB: half of the RF energy is being reflected, and thus half of the energy is being received by the device. VSWR adalah VSWR juga dapat di artikan sebagai perbandingan antara gelombang maksimum dengan gelombang minimum. If problems show up during this test, there is a very good. VSWR to Return Loss. Cable impedance ohm. S. A table of convenient values are presented at the bottom. VSWR to Return Loss (dB) Converter; Return Loss (dB) to VSWR Converter; Power Conversion : dBm - volts - watts; Phase Noise to Phase Jitter Converter; Phase Jitter to Phase Noise Converter; ppm to Hz Converter; misc. Let’s start by looking at a 2-port device illustrated in Figure 1. 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. Reflection Calculator: RL = dB: VSWR = Γ = VSWR = RL = dB: Γ = Zo . Calculate the uncertainty in gain of an amplifier due to the mismatch in impedance. Touch Down Points: This Tool will be able to calculate the down Tilt and distance of coverage from antenna for 3dB upper and lower, main loop. Return Loss is the portion of a signal that is lost due to a reflection of power at a line discontinuity. Antenna efficiency is the percentage of radiated power compared to non-relected power. The ratio of the maximum to minimum voltage is known as VSWR, or Voltage Standing Wave Ratio. The Reflection Coefficient can be calculated from return loss by using the following formula. 200mW. Upon arriving back at the source, part of the reflected wave is coupled back. VSWR of 1. 954 dB is possible. Print - Advertisement - A calculator designed to compute the VSWR, reflection coefficient, return loss and matching loss in a transmission line Inputs. Note: VSWR values were used to calculate the other two related values (rounded to 3 significant places). SFDR Visualizer You calculate return loss using the reflection coefficient, which measures the ratio of the reflected wave to the incident wave at a given point in the transmission system. Ko(mA) Fc(kHz) Kvco(MHz/v) PM(deg) Fout(MHz) Gamma: Fcomp(kHz) T31: C1: C2 R2: R3: C3:RF Two Wire Transmission Line Loss Calculator. Reflection. (3) ea 90°E-Bend - 1. In turn, reflection co-efficient is related to Return loss (RL) by the following formula: Once you have computed the Return loss, RL, VSWR can be arrived at by using the following formula: Typical values for Γ, RL, and VSWR are given below: Note: The above values are approximate only. 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. 5:1 정도로써 입력매칭이 거의 완전하게. Reflection Coefficient to Impedance Converter Convert a reflection coefficient in Magnitude Angle format into Impedance and vice versa. 1) (7. As part of Qorvo’s commitment to the engineering community, we are providing this collection of RF design tools to assist engineers. Frequency to Wavelength. 2 8. Cascaded Output IP3: O i P 3 C = 1 1 I P 3 N − 1 ⋅ G N + 1 I P 3 N [ m W] I P 3 C = 10 ⋅ l o g ( I P 3 C) [ d B m] C = cumulative up to and including stage N. If you don't want to go through complicated equations to understand the relationship between VSWR, mismatch loss, s11/gamma and would like a calculator to do it for you, check out our VSWR. VSWR is defined as the ratio of the maximum voltage to the minimum voltage in standing wave pattern along the length of a transmission line structure. 25mW. Email. Pi Attenuator Calculator. October 20, 2022. A power meter may also be used to calculate cable loss. RF Trap With Attenuator Calculator Calculates the attenuation, 'impedance', reflection coefficient, VSWR and return loss of a circuit that incorporates a RF tank circuit into a Pi attenuator. These are two different ways to measure the same thing. A high return loss is desirable and results in a lower insertion loss . From the table we can understand that when the return loss is <10dB, the antenna will be at VSWR >2, indicating the system will reflect >30% power and the performance of the antenna will be <70%. 98 dB. In some systems this is not a trivial amount and points to the need for components with low VSWR. The MAX2016 is a dual logarithmic detector/controller used to monitor the VSWR/return loss of an. 011. 25 on the worst path and the insertion loss is 0. PI Attenuator Calculator. The first reflection back from each system will be the largest and subsequent reflections will be heavily attenuated, so we. Step 2. Suitable for VHF (~1. Matching Pi Attenuator Calculator. 8. 5. These parameters are often applied to antennas, RF filters and RF amplifiers such as LNA s and PA s. 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. A common example is a power amplifier. 2. The VSWR can easily be converted into Return Loss ( RL R L ) using the following formula: RL = 20log10(VSWR + 1 VSWR − 1) R L = 20 log 10 ( V S W R + 1 V S W R − 1) Directional power meter. 54 dB (11% of your transmitter power is reflected back). 0 dB· Calculation of Free Space Path Loss and Link Budget · Calculation of T-Pad Attenuator and Stepper Motor · VSWR Return Loss and RMS Voltage calculations And that’s not all! Electronics Circuit Calculator is an all-encompassing color code calculator, a radio transmitter and a converter which offers a myriad of additional useful features. If the power incident on a load is Pi P i and the power reflected by the load is Pr P r, then the return loss in decibels is [1, 2] RLdB = 10 log Pi Pr (7. reflection coefficient definition. 1 Return loss in dB = 26. 5. Unequal-split Power Divider Calculator. For example, an antenna with a VSWR of 2:1 would have a reflection coefficient of 0. 0 or the results don't mean anything!). Please enter your values below. Fairview Microwave's Friis Transmission Equation Calculator will calculate the received power from an antenna at some distance given a transmission frequency and antenna gains. Mismatch can be specified as: the VSWR at the load end of. We can now use these values to find an equivalent loss for the line. 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. Like insertion loss, return loss is also generally described in decibels of power. 600mW. The table shows the effects of combining two components in terms of their maximum VSWR and return loss. Example 1: Cable Loss of 3 dB Cable loss: 3. Note that it blows up at the lower cutoff frequency of 6. The equivalent VSWR is 1. Calculations Pathloss / RSSI; Missmatch Loss; IP3 / SFDR Calculator; IP3, IP2, 1dB Comp. Because the reflection coefficient Γ < 1, then the return loss will have a positive dB value. Select operating frequency. Note: impedance is a complex quantity, it has real and imaginary parts or magnitude and phase; instruments are almost always calibrated for Zo being some nominal real value, is Xo=0 (eg when people speak of a 50Ω instrument, that means 50+j0Ω even if they don't. com This calculator uses the following formulas for converting the values between the VSWR, return loss, reflection coefficient, and mismatch loss. Return Loss has surfaced in our ham world due to the new handheld antenna system analyzers like the Nano VNA and others. There are two S-parameters of interest. Reflection Calculator. Marki Microwave's Tools is a collection of free online applications for RF analysis and synthesis that are easy to use and mobile-friendly. What is a Vswr To Rl? VSWR (Voltage Standing Wave Ratio) to RL (Return Loss) is a conversion used in radio frequency (RF) engineering to measure the efficiency of power. To calculate the Return Loss, add 1 to the VSWR and divide the result by the VSWR minus 1. Moreover, return loss is the relationship between both the reflection coefficient (Γ) and the. Reflection -10dB: 1/10 th of the RF energy is being reflected. Return loss vs. Return Loss to VSWR Conversion Chart. 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. From this the reflection factor Γ and the Voltage Standing Wave Ratio (VSWR or SWR) could be determined using the following definitions: – Γ is defined as the ratio of the electrical field strength Eof the reflected wave over the forward travelling wave: Γ = Eof reflected wave Eof forward traveling wave. Mismatch Loss (dB). A calculator designed to compute the VSWR, reflection coefficient, return loss and matching loss in a transmission lineThis VSWR / Return Loss calculator allows you to compute corresponding VSWR, Return Loss, Reflection coefficient and Mismatch Loss values for the entered input value and. Cell Site Commissioning and Maintenance. g. 43. The losses are due to copper losses/skin loss and for more esoteric antennas (planar types) it's usually dielectric loss. VSWR Calculator. Return Loss to VSWR Calculator. Skin Depth Calculator. Assuming that the source and load are perfect then when the signal from the source arrives at the switch some of that signal is reflected. VSWR Return Loss Calculator. Stripline Impedance Calculator Calculate Stripline impedance for given PCB parameters. Enter Your Values. 01. Any other value indicates that a portion of the energy is reflected. The. Lumped Quadrature Coupler Designer Enter the frequency of operation and system Z0. The return loss conversion table is a valuable tool for antenna engineers, allowing them to quickly and accurately convert the VSWR values they measure into return loss values. Low-pass lumped element filters. Interactive Tools & Calculators. 200mW. What is the VSWR ratio to return loss? There is an inverse relationship between Voltage Standing Wave Ratio (VSWR) and Return Loss. Next, plug in the calculated return loss value into the formula VSWR = (1 + 10^ (RL/20))/ (1 - 10^ (RL/20)). At 1000 MHz, the S11 (dB) = -RL (dB) = -15 dB. Yes, we did that without a calculator. This is the most efficient scenario. Calculate VSWR, Return Loss, etc. Calculate VSWR, Return Loss, Reflection Coefficient, Match Efficiency, and Net Transmission Loss from an RF broadcast transmitters forward and reflected power readings. The return loss of a system is defined as the ratio of incident power to reflected power and is measured in dB. Both decimal point and comma are ok. Return Loss [dB] Input Power [dBm] [W] VSWR :1 : Mismatch Loss [dB] Reflection Coefficient : Reflected Power [dBm] [W] Output Power [dBm] [W] Share your thoughts. Pasternack's Friis Transmission Equation Calculator is a path loss calculation measurement tool that calculates the received power from an antenna at some distance given a transmission frequency and antenna gains. 2. PI Attenuator Calculator. Return Loss (dB) 3. 5dB loss per 100 feet at 146 MHz). VSWR to Return Loss (dB) Calculator. This test determines the return loss value of each connector pair, cable component and cable to identify the problem location. VSWR Return Loss (dBm) VSWR Return Loss (dBm) VSWR Return Loss (dBm) VSWR. Print - Advertisement - A calculator designed to. Values for L, C1 and C2 and R will be calculated. VSWR, or the Voltage Standing Wave Ratio, is the ratio of the maximum standing wave amplitude at one node to the minimum amplitude at another node in a system. Click here to use the VSWR Calculator. VSWR is referring to the maximum and minimum voltage values that is being transmitted and reflected by the component. VSWR = Voltage standing wave ratio. VSWR and Return Loss RF Calculator. Learn about voltage standing wave ratio (VSWR), return loss, and mismatch loss, which helps characterize the wave reflections in a radio frequency (RF) design. Calculates the resistor values, attenuation, minimum attenuation, 'impedance', reflection coefficient, VSWR and return loss of a matching Pi attenuator. The reflection coefficient is calculated from the VSWR and used to compute the mismatch loss in dB as shown below. The VSWR monitoring system consists of an ADC for real-time measurements. ,100 % power transferred from a source to a load via a transmission line/cable). This calculator uses the following formulas for converting the values between the VSWR, return loss, reflection coefficient, and mismatch loss. While we’re at it, the reflection coefficient is: Γ=(75-50)/(75+50)=0. 00Watts Enter 1. 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. 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. Stripline Impedance calculator Smith charts VSWR/Return loss converter Wavelength calculator Wilkinson splitter designer. The MAX2016 outputs the difference between the two power detectors. We can then find the return loss as -20 * log(0. 5:1. The following formula is used to calculate the Return Loss (RL) from Voltage Standing Wave Ratio (VSWR). In addition, if GAMMA, VSWR, or dB is known, the calculator can convert between the three. 5:1 is considered ideal in the RF field, and. 00Watts = 1. 7145 VSWR 6 Directivit y of directiona l coupler 23 dB 0. Because the reflection coefficient Γ < 1, then the return loss will have a positive dB value. If VSWR is known, then the reflection coefficient (Γ), return loss (RL), and mismatch loss (ML) is calculated by using following formulas. VSWR: RL (dB) 1. , some amount of incident power will reflect the source in a practical system). Hence, the return loss is always lower than the ideal system (i. Γ = (VSWR – 1)/(VSWR + 1) Return Loss (dB) = -20*Log 10 (|Γ|) Mismatch Loss (dB) = -10*Log 10 (1 – |Γ| 2) Conversion Tables. USA CHINA MALAYSIA INDIA ISRAEL UNITED KINGDOM. 4. Pasternack's VSWR/Return Loss Calculator finds VSWR, Return Loss, Mismatch Loss, and the Reflection Coefficient given any one of the listed input types. Note the same numerals are used with just a shift in the decimal point. If you don't have Excel you can. Where, RL = Return loss in dB. It's located in our download area . The concept of loss factor is discussed on this page. The calculator on this page helps determine the loss and that can be factored into the design or RF link budget. For S 11 it is also possible to display return loss and (voltage) standing wave ratio [(V)SWR] over frequency range. 0:1). Transmission Power. 0. To calculate the Return Loss, add 1 to the VSWR and divide the result. Click here to use the VSWR Calculator. 0:1, 2. Moreover, return loss is the relationship between both the reflection coefficient (Γ) and the. 72 0. Calculates the resistor values, attenuation, 'impedance', reflection coefficient, VSWR and return loss of a Pi attenuator. 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. 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. Enter the source characteristic impedance and the load impedance then press "Calculate" below. 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. Insertion loss causes due to two factors namely ohmic loss, dielectric leakage and the return loss is caused due to mismatched systems. e. Calculate Effective Radiated Power (ERP) With Known Transmission Variables: Transmitter Output Power : W or kW. S-parameters are a valuable tool for calculating reflection coefficients and transmission gains for a two-port network's input and output sides. 14 dB per hundred feet. It tells the severity of standing waves in a transmission line. Stripline Calculator. Suppose the wave is not matched with load and signal there is some unwanted signals are interrupted or signal loss is occurred. 3. 98dB = 96. This calculator converts values between VSWR, Return loss, Reflection Coefficient and Mis-Match Loss. 1) (2. By the way, here is a page that summarizes Greek letter usage in Microwave Engineering. 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. This ratio represented in dB is called as Return Loss. Suppose the wave is not matched with load and signal. Like insertion loss, return loss is also generally described in decibels of power. $ = Gamma^2 = 10^{-RL/10}$ Power transmitted ratio for system 1 is 0. VSWR table of return loss vs. Author: yuuki. A VSWR of 1:1 means that there is no power being reflected back to the source. 0. Return Loss and Mismatch Loss Calculator. However, each field, when changed will allow. S22 would be the reflected power radio 2 is attempting to deliver to antenna 2. Stripline Impedance calculator Smith charts VSWR/Return loss converter Wavelength calculator Wilkinson splitter designer. VSWR is a measure of the reflected power on a transmission line. MatchCalc™ RF Design Calculator. from Forward and Reflected Power: Transmitter Forward Power : Watts: System Reflected Power : Watts: VSWR = Reflection Coefficient = Return Loss = dB: Match Efficiency = % Net. Return loss and insertion loss are both measurements of how a component or device affects the transmission of signals in a system. Telegram. The path loss that might be measured in a system however will not be this. At 100 MHz, the loss is 0. This mix of web-based tools and downloadable Windows software was developed to help engineers design faster and more accurately. Created Date: 10/21/2015 12:42:40 PM. Click here to use the VSWR. You can use our VSWR calculator to see that 1. The reflection coefficient is also known as s11 or return loss. WhatsApp. This is an online conversion tool for converting between VSWR, return loss and reflection coefficient, which are different ways to express how well a load is matched to a source. The calculator is a spreadsheet that accepts VSWR specifications for all the components in your RF Path—tower mounted amplifiers, diplexers, bias tees, etc. 9913 and LMR-400 are popular “low-loss” RG-8 types. 5:1 is considered ideal in the. voltage standing wave ratio 020710. 02:1 VSWR VSWRHighSide of 1. Introduction Input Type: Input Value: Calculate Reset Definition of VSWR "Understanding VSWR isn't just about crunching numbers; it's about shaping the future of efficient wireless communication. מדריך שלם ל- VSWR מ-FMUSER [עודכן 2022] בתורת האנטנות, VSWR מקוצר מיחס גל עומד מתח. Conclusion: In summary, RL and VSWR formulas and calculators are valuable tools that enhance the efficiency, accuracy and consistency of RF engineering tasks such as measurement, analysis, troubleshooting and system design. These multiple solutions are possible because each contributor is a vector having both. Here Click here to learn more about VSWR. Email. How to improve the Return Loss of an amplifier. 1) RL dB = 10 log P i P r. 5:1 VSWR is equivalent to -13. Select operating frequency. Linkedin. These calculators help with unit conversions, VSWR calculations, attenuator design, antenna design, radars, and various other basic calculations that are often required. The power reflected back from an antenna is specified using either the voltage standing wave ratio (VSWR) or the reflection coefficient (also referred to as return loss). Calculates the resistor values, attenuation, minimum attenuation, impedance, reflection coefficient, VSWR and return loss of an impedance matching T attenuator. However, convention and some literature quote return loss as a negative value akin to an S (1,1) measurement on a Network. coefficient of Port 1 (also called return loss), and. Now let's look at the response. Expressed as 3. You can assume power dissipation to be uniform, provided the assembly does not operate in high VSWR/return-loss conditions. 12 VSWR max. (also called insertion loss). 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. Reflections are measured using either VSWR or Return Loss. It is specified in decibels (dB) relative to a short circuit (100 percent rejection). Note: The historical definition of return loss results in a negative sign. An ideal value of VSWR is 1 where none of the power is reflected and all of it is transmitted forward. See the vswr table below to see a numerical mapping between reflected power, s11 and VSWR. 2. Enter. Values for L1, L2 and C will be calculated. Return loss is a measure in dB of the ratio of power in the incident wave to that in the reflected wave, and we define it to have a negative value. This VSWR calculator will calculate return loss, mismatch loss, loss in percentage and the reflection coefficient. Calculate return loss, reflection attenuation from a VSWR level. 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. (GHz) Nut Attach Attach /Pin in (mm) in (mm) lb (g)A VSWR of 1:1 indicates a perfect match, meaning all power is being efficiently transferred, while higher values suggest mismatches and power loss. 5dB loss per 100 feet at 146 MHz). RETURN RETURN RETURN RETURN RETURN LOSS VSWR LOSS VSWR LOSS VSWR LOSS VSWR LOSS VSWR (dB) (dB) (dB) (dB) (dB) return loss Vs. Watts the reflected power would be 1 Watt. VSWR (Voltage Standing Wave Ratio) and Return Loss both measure the same parameter i. WhatsApp. 8ghz. VSWR & Return Loss Calculator: Enter forward and reflected power or match to determine equivalent values. As an added bonus, the results are modifiable and can calculate the other values. Reflection. A network analyzer can be used to make S parameter measurements. Select the FREQ-RETURN LOSS using the Up/Down arrow key and press ENTER. Return loss can be measured by using microwave and RF test. Stripline Impedance calculator Smith charts VSWR/Return loss converter Wavelength calculator Wilkinson splitter designer. This calculator is specific to the circuit used in the RF Trap With Attenuators FLEXI-BOX. The low-pass filter often is a natural choice for lumped element filters. Coupling to Direct Line Insertion Loss Conversion Table for Directional Couplers. The online calculators are usable in pop-up mode for easy desktop. RF Calculators. voltage standing wave ratio. This reduction of signal, also called attenuation, is directly related to the length of a cable—the longer the cable, the greater the insertion loss. Effects of Cable Loss in VSWR and Return Loss Measurements By Jim Norton Bird Technologies Group Applications Engineer 1 | Bird Technologies Group 866. A series of RF calculators for radio frequency engineers. If our directional coupler had perfect isolation, the return loss of the load would equal the difference between the reflected and forward measurements:. Example 2. *Strictly, a loss quantity when expressed in dB should be positive. Return loss is the fiber optic light gets reflected back at the connection point. Forward. Consider the antenna being used in transmit mode. ← Conducted RF Environments With Real RF Devices Vs. Therefore, the line can have a maximum loss of 2. 000Match Efficiency (%) Calculates Match Efficiency. The following table provides conversions for wavelength (from frequency), VSWR (from forward and reflected power). In practice, the generally accepted frequency band limits for rectangular waveguide are between 125% and 189% of the lower cutoff frequency, in this case 8. Due to reflections, an additional loss of 0. The formula for insertion loss in decibels (dB) is: Insertion Loss (dB) = 10 * log10 (Pin / Pout) Where: Pin is the input power or signal level. VSWR Return Loss Calculator VSWR is the voltage standing wave ratio it used to measure the all-types waves (example: antenna waves) during transmission. At the same time another trace can be set to display the VSWR. 8ghz. Return loss vs. Stripline Impedance calculator Smith charts VSWR/Return loss converter Wavelength calculator Wilkinson splitter designer. 50:1, the resulting maximum VSWR will be 4. 6dB. 특히 Return loss와 VSWR의 대략적 값의 관계정도는 암기해두는게 편리할 때가 많다. comTwo years ago, one of our most respected RF experts, Lou Meyer, wrote a blog post describing the technicalities of return loss and voltage standing wave ratio (VSWR) and how the multiple components at a cell site tower make the calculations more complex. For example, an antenna with a VSWR of 2:1 would have a reflection coefficient of 0. Assuming the systems have no internal loss. This VSWR calculator will calculate return loss, mismatch loss, loss in percentage and the reflection coefficient. This calculator converts values between VSWR, Return loss, Reflection Coefficient and Mis-Match Loss. 16-Feb-2022. The ratio of the input to the reflected signal is called the Voltage Standing Wave Ratio (VSWR). The return loss at the input and output ports can be calculated from the reflection coefficient, S11 or S22, as follows: RLIN = 20log10|S11| dB (Eq. 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. As an example, F1=750 MHz and F2=850 MHz for a typical cellular frequency band. 009. 2 means a peak voltage 1. 예를 들어 Return loss가 10dB 정도라면, VSWR은 2:1 이하가 되어서 입력매칭이 비교적 잘된 경우로 평가하며, Return loss가 14 dB 정도가 되면 VSWR은 1. (1)vswr return loss calculator waveguide calculator circular waveguide calculator rectangular wavelength tem calculator wire loop inductance calculator wire microstrip impedance calculator wire over plane inductance calculator wire self inductance calculator wire stripline impedance calculator. This calculator converts Return loss (RL) to Voltage Standing Wave Ratio (VSWR). The loss goes to infinity at the lower cutoff frequency. As an example, input power of 100 W (50 dBm) and output of 50 W (47 dBm) yields a cable. 54-88 MHz -- Low VHF; 88-108 MHz -- FM;S11 then would be the reflected power radio 1 is trying to deliver to antenna 1. VSWR is defined as the maximum voltage of the standing wave (E max) to the minimum voltage of the standing wave (E min ). Noise Factor to Noise Figure Calculator. 79.