# wavelength, frequency
Converter for wavelength to frequency and vice versa.
Insert 1 of
 - wavelength in m
 - frequency in MHz

# transmitting power, distance, e-field strength
Calculation of E-field strength or transmitting power or distance in relation to other ones.
Insert 2 of
 - E-Field strength in dBuV/m
 - distance in km
 - transmitting power in dBm
Select the value to calculate by checkbox.

# frequency, distance, space lost
Calculation of frequency or distance or space lost in relation to other ones.
Insert 2 of
 - frequency in MHz
 - distance in km
 - space lost in dB
Select the value to calculate by checkbox.

# e-field strength, h-field strength, powerdensity
Converter for E-field or H-field or powerdensity to other ones.
Insert 1 of
 - E-field strength in dBuV/m
 - H-field strength in dBuA/m
 - Power Density in dBmW/mē
 
# e-field strength, frequency, receive power
Calculation of E-field strength or frequency or receive power in relation to other ones.
Insert 2 of
 - E-field strength in dBuV/m
 - frequency in MHz
 - receive power in dBm
Select the value to calculate by checkbox.

# adc gain, adc fs voltage, headroom, input power
Calculation of ADC gain, ADC full scale voltage, headroom, input power in relation to other ones.
Typical full scale values for ADCs are 1.0 to 2.5V.
Insert 3 of
 - ADC full path gain (from SDR input to ADC) in dB
 - ADC full scale voltage in V
 - headroom in dB
 - input power in dBm
Select the value to calculate by checkbox.

# power, voltage, load resistance
Converter for power and voltage to relative values and vice versa.
Insert 1 of
 - power in (f,p,n,u,m,k)W
 - voltage in (u,m)V 
 - power in dBm
 - voltage in dBuV
Insert
 - load resistance in Ohm

# fft size, adc enob, noise floor
Calculation of FFT size, ADC ENOB, noise floor to full scale distance in relation to other ones.
ADC ENOB means the effective number of bits and is mostly lower than the nominal number of bits.
Amplifier, ADC reference voltage and ADC quantization will produce noise that will be affected in limited dynamic.
Noise is normally equally distributed over the frequency and a FFT will show this as a noise power density.
FFT size, ENOB and noise floor can be measured or captured with the sodiraSDR measure module.
With FTT size = 1 you will get the ADC dynamic range.
Insert 2 of
 - FFT size
 - ADC ENOB
 - noise floor to full scale distance in dB
Select the value to calculate by checkbox.

# antenna nf, lna nf, lna gain, adc nf
Calculation of system noise performance need the part of noise
 - from antenna or other input sources
 - from amplifier (LNA)
 - from ADC
For characterizing of the degration the noise figure (NF) or noise factor (F) will be used. Noise figure is the ratio of noise in relation to thermal noise at 290K.
The antenna noise or environment noise can be captured from calculation tab environment noise.
The NF of ADC can be calculated from ADC parameter full scale voltage, effective number of bits (ENOB) and samplerate.
The NF of ADC is relative high but the system NF will be decreased by a low noise amplifier (LNA) prior the ADC.

Calculates the
- ADC NF in dB
- summary or system NF in dB
- dominant noise source

Insert
 - noise figure from antenna in dB
 - noise figure of amplifier in dB
 - gain of amplifier in dB
 - ADC full scale voltage in V
 - ADC ENOB
 - ADC samplerate in kHz

# noise power
Calculation of noise power in relation to bandwidth and system noise figure (NF).
Calculation of thermal noise power in relation to bandwidth.
Insert
 - bandwidth in Hz
 
# environment noise
Calculation of of noise figure in relation to environment category and frequency.
In addition the noise level in relation to bandwidth and antenna factor will be calculated.
The antenna factor can be get by measurement or by tab short monopol antenna or small loop antenna.
The categories are defined by ITU-R P.372 document.
Insert
 - frequency in MHz
 - antenna factor in dB/m
 - bandwidth in Hz
 
# short monopole antenna
Calculation of some data of a short vertically monopol. Short is defined typically lower than 1/10 of wavelength.
A short monopol has a high capacitive impedance and in series to a load resistance the antenna factor depends to frequency. 
A impedance converter will be help to get a low frequency dependency. Such a impedance converter is used in this calculation.
The load resistor means the load in series to the monopol.

Calculation of
 - cutoff frequency
 - maximal useable frequency
 - power at 50 Ohm
 - antenna factor

Insert
 - length in m
 - load resistance in kOhm
 - E-field strength in dBuV/m
 - frequency in MHz
 
# small loop antenna
Calculation of some data of a small magnetic loop antenna. Small loop is typically defined as diameter is lower than 1/10 of wavelength.
A small loop antenna has a low inductive impedance and in series to a load resistance the antenna factor depends to frequency.
A impedance converter will be help to get a low frequency dependency. Such a impedance converter is used in this calculation.
The closed loop will be used with a short circuit and a current to voltage (I-U) converter (transimpedance amplifier). 
The open loop will be used with low to high resistor in parallel to the loop and optional with voltage amplifier.
This 3 types of operation can be used in this calculation.

Calculation of
 - inductance
 - DC resistance
 - cutoff frequency
 - wire length
 - antenna factor
 - frequency in MHz
 
Insert
 - type of operation 
 - number of turns
 - diameter of loop in m
 - diameter of wire in mm
 - load resistance in Ohm
 - E-field strength in dBuV/m
 - frequency in MHz
 
