HomeBird Electronic Corporation www.bird-electronic.com (866)
695-4569 2/6/06 JNBy: Jim Norton, Applications EngineerRF
CalculatorsSelect a calculator tab at the bottom of this page for
assistance with your radio frequency (RF) needs.Calculators
available include Power, VSWR & Return Loss, Frequency &
Wavelength,Attenuation, Directivity, Cable Loss, Masking
Effect,Field Strength, Free Space Loss and Metric Conversions.
PowerBird Electronic Corporation www.bird-electronic.com (866)
695-4569 JNPower CalculatorEnter power and select units to
determine equivalent values.Enter100.0006Power =50.000dBmPower
=100,000,000,000,000.000Picowatts (pW)Power
=100,000,000,000.000Nanowatts (nW)Power =100,000,000.000Microwatts
(uW)Power =100,000.000Milliwatts (mW)Power =100.000Watts (W)Power
=0.100Kilowatts (kW)1 kW = 1,000 W 1 W = 1,000 mW = 1,000,000 uW1 W
= 1,000,000,000 nW = 1,000,000,000,000 pWPower (dBm) = 10 x Log [
Power (Watts) ] + 30 dB
VSWR & RLBird Electronic Corporation www.bird-electronic.com
(866) 695-4569 JNVSWR & Return Loss CalculatorEnter forward and
reflected power or match to determine equivalent
values.EnterForward Power2.00WattsEnter1.2001EnterReflected
Power4.00Watts=1.200VSWRCalculatesVSWR-5.83=-20.828Return Loss
(dB)CalculatesReturn Loss3.01dB=99.174Match Efficiency
(%)CalculatesMatch
Efficiency-100.00%=0.091RhoCalculatesRho1.41EnterPower33.00WattsVSWR
= Voltage Standing Wave RatioCalculatesPower45.19dBmPf = Forward
Power (Watts)Pr = Reflected Power (Watts)EnterPower33.00dBmVSWR =
[1+Sqrt(Pr / Pf)] / [1-Sqrt(Pr / Pf)]CalculatesPower2.00WattsReturn
Loss (dB) = 10 x Log ( Pr / Pf )Match Efficiency (%) = 100% x (1 -
Pr / Pf)Power (dBm) = 10 x Log [ Power (Watts) ] + 30 dBRho = Sqrt
( Pr / Pf )
Freq & WaveBird Electronic Corporation
www.bird-electronic.com (866) 695-4569 JNFrequency & Wavelength
CalculatorEnter frequency or wavelength and select units to
determine equivalent values.Enter900.0002Frequency
=900,000.000Kilohertz (kHz)Frequency =900.000Megahertz
(MHz)Frequency =0.900Gigahertz (GHz)Wavelength =0.333Meters
(m)Wavelength =33.333Centimeters (cm)Wavelength =1.094Feet
(ft)Wavelength =13.123Inches (in)1 MHz = 1,000 kHz 1 GHz = 1,000
MHzWavelength (Meters) = 300 / Frequency (MHz)
AttenBird Electronic Corporation www.bird-electronic.com (866)
695-4569 JNAttenuation CalculatorEnter power or attenuation to
determine values.EnterInput Power2.00WattsEnterInput
Power50.00WattsEnterOutput
Power2.00WattsEnterAttenuation3.00dBCalculatesInput
Power33.01dBmCalculatesInput Power46.99dBmCalculatesOutput
Power33.01dBmCalculatesOutput
Power43.99dBmCalculatesAttenuation0.00dBCalculatesOutput
Power25.06WattsEnterPower3.00WattsEnterOutput
Power2.00WattsCalculatesPower34.77dBmEnterAttenuation0.00dBCalculatesOutput
Power33.01dBmEnterPower47.00dBmCalculatesInput
Power33.01dBmCalculatesPower50.12WattsCalculatesInput
Power2.00WattsOutput Power (dBm) = Input Power (dBm) - Attenuation
(dB)Power (dBm) = 10 x Log [ Power (Watts) ] + 30 dB
DirectivityBird Electronic Corporation www.bird-electronic.com
(866) 695-4569 JNDirectivity Error CalculatorEnter directivity,
forward power and reflected power to determine directivity
errors.EnterDirectivity of Coupler30.000dBDirectivity is a measure
of the ability of aEnterForward Power100.000Wattsdirectional
coupler to discern between theEnterReflected Power4.000Wattsforward
and reflected traveling wave in aCalculatesForward Power
Minimum98.739Wattstransmission system.CalculatesForward Power
Maximum101.269WattsCalculatesForward Power Min Error-1.261%Power
meters, antenna monitors andCalculatesForward Power Max
Error1.269%analyzers are coupler based testCalculatesReflected
Power Minimum2.835Wattsequipment which are used to
measureCalculatesReflected Power Maximum5.365Wattsforward and
reflected power as well asCalculatesReflected Power Min
Error-29.123%VSWR and return loss.CalculatesReflected Power Max
Error34.123%CalculatesVSWR Minimum1.402Directivity errors result in
measurementsCalculatesVSWR1.500which may vary between maximum
andCalculatesVSWR Maximum1.608minimum values.CalculatesReturn Loss
Minimum-15.529dBCalculatesReturn Loss-13.979dBCalculatesReturn Loss
Maximum-12.649dBThe following is a step-by-step procedure to
calculate the results which are displayed above:GivenDirectivity of
Coupler30.000dBDir = Directivity of CouplerGivenForward
Power100.000WattsPf = Forward PowerGivenReflected Power4.000WattsPr
= Reflected PowerCalculatesDirectivity Power Ratio1,000Directivity
Power Ratio = 10 ^ (Dir / 10)CalculatesDirectivity Forward
Power0.004WattsPfd = Pr / Directivity Power
RatioCalculatesDirectivity Reflected Power0.100WattsPrd = Pf /
Directivity Power RatioCalculatesForward Voltage70.711VoltsVf =
Sqrt (Pf x 50 Ohms)CalculatesReflected Voltage14.142VoltsVr = Sqrt
(Pr x 50 Ohms)CalculatesDirectivity Forward Voltage0.447VoltsVfd =
Sqrt (Pfd x 50 Ohms)CalculatesDirectivity Reflected
Voltage2.236VoltsVrd = Sqrt (Prd x 50 Ohms)Note, voltage vectors
add when in phase or subtract when 180 degrees out of phase with
each otherCalculatesForward Voltage Minimum70.263VoltsVf (Min) = Vf
- VfdCalculatesForward Voltage Maximum71.158VoltsVf (Max) = Vf +
VfdCalculatesReflected Voltage Minimum11.906VoltsVr (Min) = Vr -
Vrd (or 0 if Vrd > Vr)CalculatesReflected Voltage
Maximum16.378VoltsVr (Max) = Vr + VrdCalculatesForward Power
Minimum98.739WattsPf (Min) = (Vf (Min) ^ 2) / 50
OhmsCalculatesForward Power Min Error-1.261%Error = 100% x (Pf
(Min) - Pf) / PfCalculatesForward Power Maximum101.269WattsPf (Max)
= (Vf (Max) ^ 2) / 50 OhmsCalculatesForward Power Max
Error1.269%Error = 100% x (Pf (Max) - Pf) / PfCalculatesReflected
Power Minimum2.835WattsPr (Min) = (Vr (Min) ^ 2) / 50
OhmsCalculatesReflected Power Min Error-29.123%Error = 100% x (Pr
(Min) - Pr) / PrCalculatesReflected Power Maximum5.365WattsPr (Max)
= (Vr (Max) ^ 2) / 50 OhmsCalculatesReflected Power Max
Error34.123%Error = 100% x (Pr (Max) - Pr) / PrCalculatesRho
Minimum0.167Rho (Min) = Sqrt (Pr (Min) / Pf
(Max))CalculatesRho0.200Rho = Sqrt (Pr / Pf)CalculatesRho
Maximum0.233Rho (Max) = Sqrt (Pr (Max) / Pf (Min))CalculatesVSWR
Minimum1.402VSWR (Min) = (1 + Rho (Min)) / (1 - Rho
(Min))CalculatesVSWR1.500VSWR = (1 + Rho) / (1 - Rho)CalculatesVSWR
Maximum1.608VSWR (Max) = (1 + Rho (Max)) / (1 - Rho
(Max))CalculatesReturn Loss Minimum-15.529dBReturn Loss (Min) = 10
x Log (Pr (Min) / Pf (Max))CalculatesReturn Loss-13.979dBReturn
Loss = 10 x Log ( Pr / Pf )CalculatesReturn Loss
Maximum-12.649dBReturn Loss (Max) = 10 x Log (Pr (Max) / Pf
(Min))
Cable LossBird Electronic Corporation www.bird-electronic.com
(866) 695-4569 JNCable Loss CalculatorEnter cable, jumper,
connector and other loss parameters to determine transmission cable
system insertion loss.Cable loss is the total insertion loss of
your transmission cable system.This typically includes insertion
loss of the transmission cable, jumper cables, connectors and
lightning protection.Loss of other components (e.g. VSWR/power
monitor, duplexer, combiner or filter) may also come into
play.EnterCable Loss/100 m or ft6.80dBLoss per 100 Meters or Feet
at FrequencyEnterCable Length (m or ft)50.00m or ftLength in Meters
or FeetCalculatesCable Loss3.40dBTransmission Cable Insertion
LossEnterTop Jumper Loss/100 m or ft3.23dBLoss per 100 Meters or
Feet at FrequencyEnterTop Jumper Length (m or ft)10.00m or ftLength
in Meters or FeetCalculatesTop Jumper Loss0.32dBTop/Antenna Jumper
Cable Insertion LossEnterBottom Jumper Loss/100 m or ft3.23dBLoss
per 100 Meters or Feet at FrequencyEnterBottom Jumper Length (m or
ft)20.00m or ftLength in Meters or FeetCalculatesBottom Jumper
Loss0.65dBBottom/Tx Jumper Cable Insertion LossEnterLoss per
Connector0.05dBConnector Insertion LossEnterNumber of
Connectors8Two Connectors per PairCalculatesConnector
Loss0.40dBConnector Insertion LossEnterLightning Protection
Loss0.10dBLightning Protection Insertion LossEnterVSWR/Power
Monitor Loss0.00dBVSWR/Power Monitor Insertion LossEnterOther
Component Loss0.00dBLoss of Combiner, Duplexer, Filter,
etc.CalculatesTotal Cable System Loss4.87dBTransmission Cable
System Insertion Loss
Masking EffectBird Electronic Corporation
www.bird-electronic.com (866) 695-4569 JNMasking Effect
CalculatorEnter cable loss and match or forward and reflected power
to determine the masking effect.EnterCable Insertion
Loss3.00dBAntenna measurements takenEnterVSWR at Transmitter1.50at
the transmitter end of the cableCalculatesVSWR of Antenna2.33will
be masked by the cable loss.EnterCable Insertion Loss3.00dBCL =
Cable Insertion LossEnterReturn Loss at Transmitter-14.00dBRLt =
Return Loss at TransmitterCalculatesReturn Loss of
Antenna-8.00dBRLa = Return Loss of Antenna = RLt - (2 x
CL)EnterCable Insertion Loss3.00dBCL = Cable Insertion
LossEnterForward Power at Transmitter100.00WattsPft = Forward Power
at TransmitterEnterReflected Power at Transmitter4.00WattsPrt =
Reflected Power at TransmitterCalculatesRho at Transmitter0.20Rhot
= Sqrt (Prt / Pft)CalculatesVSWR at Transmitter1.50VSWRt = (1 +
Rhot) / (1 - Rhot)CalculatesReturn Loss at Transmitter-13.98dBRLt =
10 x Log (Prt / Pft)CalculatesForward Power at
Transmitter50.00dBmPft (dBm) = 10 x Log (Pft (Watts)) + 30
dBCalculatesForward Power at Antenna47.00dBmPfa (dBm) = Pft (dBm) +
CLCalculatesReflected Power at Transmitter36.02dBmPrt (dBm) = 10 x
Log (Prt (Watts)) + 30 dBCalculatesReflected Power at
Antenna39.02dBmPra (dBm) = Prt (dBm) - CLCalculatesForward Power at
Antenna50.12WattsPfa (Watts) = 10 ^ ((Pfa (dBm) - 30) /
10)CalculatesReflected Power at Antenna7.98WattsPra (Watts) = 10 ^
((Pra (dBm) - 30) / 10)CalculatesRho of Antenna0.40Rhoa = Rho of
Antenna = Sqrt (Pra / Pfa)CalculatesVSWR of Antenna2.33VSWRa = (1 +
Rhoa) / (1 - Rhoa)CalculatesReturn Loss of Antenna-7.98dBRLa = 10 x
Log (Pra / Pfa)
Field StrengthBird Electronic Corporation
www.bird-electronic.com (866) 695-4569 JNField Strength
CalculatorEnter signal power level, frequency and antenna gain to
determine field strength.EnterSignal Power Level33.000dBmThe field
strength of the signal emittedEnterFrequency900.000MHzby a radio
antenna is usually expressedEnterReceive Antenna Gain2.000dBin
units of microvolts per meter (uV/m).CalculatesAntenna
Factor27.285dBCalculatesSignal Level140.000dBuVThis may be
calculated if the signal powerCalculatesSignal
Level167.285dBuV/mlevel (dBm), frequency and the gain of
theCalculatesField Strength231.336V/mreceive antenna are
known.CalculatesField Strength231,335.620mV/mCalculatesField
Strength231,335,620.449uV/mAntenna Factor (dB) = 20 Log (Frequency
(MHz)) - Antenna Gain (dB) -29.8Signal Level (dBuV) = Signal Level
(dBm) + 107 dBSignal Level (dBuV/m) = Signal Level (dBuV) + Antenna
Factor (dB)Field Strength (uV/m) = 10 ^ (Signal Level (dBuV/m) /
20)1 V/m = 1,000 mV/m = 1,000,000 uVm
Free Space LossBird Electronic Corporation
www.bird-electronic.com (866) 695-4569 JNFree Space Loss
CalculatorEnter frequency and distance to determine free space
loss.EnterFrequency900.000MHzFree Space Loss is the power loss of
aEnterDistance1.000Milesradio signal as it travels through free
space.CalculatesFree Space Loss95.685dBLosses due to sources such
as earth, trees,buildings, cables and connectors as well
asEnterFrequency900.000MHzantenna gains are not
considered.EnterDistance0.001KilometersCalculatesFree Space
Loss31.552dBFree Space Loss (dB) = 36.6 + 20 x Log (Frequency (MHz)
x Distance (Miles))1 Mile = 1.6093 Kilometers
MetricBird Electronic Corporation www.bird-electronic.com (866)
695-4569 JNMetric ConversionsEnter quantity and select units to
determine equivalent
values.LengthWeightEnter1.0007Enter1.0004=160,934.400Centimeters
(cm)=1,000.000Grams (g)=63,360.034Inches (in)=35.274Ounces
(oz)=5,279.936Feet (ft)=2.205Pounds (lb)=1,759.979Yards
(yd)=1.000Kilograms (kg)=1,609.344Meters (m)=0.022Hundredwt
(cwt)=1.609Kilometers (km)=0.001Tons (ton)=1.000Miles
(mi)=0.001Tonnes (t)1 in = 2.54 cm 1 m = 3.28 ft 1 mi = 1.6 km1 oz
= 28.35 g 1 kg = 2.2 lb 1 t = 1.1
tonAreaTemperatureEnter1.0004Enter0.0002=10,000.000Square
cm=32.000Fahrenheit (F)=1,550.005Square in=0.000Celsius
(C)=10.764Square ft=491.690Rankine (R)=1.000Square m=273.150Kelvin
(K)=0.000Acres=0.000Square kmC = 5/9 (F - 32)=0.000Square miR = F +
459.69 K = C + 273.151 sq in = 6.45 sq cm 1 sq m = 10.76 sq ft1 sq
mi = 2.6 sq kmVolumeEnter2.0004=2,000.000Milliliters
(ml)=67.628Fluid Oz (fl oz)=2.113Quarts (qt)=2.000Liters
(l)=0.528Gallons (gal)=0.071Cubic Ft (cu ft)=0.002Cubic M (cu m)1
fl oz = 29.6 ml 1 liter = 1.06 qt1 gal = 3.8 liters 1 cu m = 35.3
cu ft
