Radio

This section has a set of radio and radio performance calculations.

 

Rcvr Noise

Enter the inputs Temperature in Kelvin, Bandwidth in Hz, ENR (Excess Noise Ratio) of Source in dB, Pre-Amp Gain in dB the Radio Noise Figure in dBF and the Radio Gain in dB and press “Calculate” to get the Radio Output Power in dBm per Hz.   Press “Clear” to clear the coefficients and begin over. Press the “Close” button to quit the screen and go back to main menu.  The temperature defaults to 290K (room temp 27C) some of the other parameters such as bandwidth also default to help prevent errors in the calculation caused by blanks or zeros.

 

Figure 123 – Radio Rcvr Noise Power


SFDR

Enter the inputs Temperature in Kelvin, Bandwidth in Hz, the Radio Noise Figure in dBF and the Radio 2nd and/or the 3rd order IMD or Inter-Modulation in Output Power dBm and press “Calculate” to get the Radio Spurious Free Dynamic Range for 2nd and/or 3rd order products.  Press “Clear” to clear the coefficients and begin over. Press the “Close” button to quit the screen and go back to main menu.  The temperature defaults to 290K (room temp 27C) some of the other parameters such as bandwidth also default to help prevent errors in the calculation caused by blanks or zeros.

 

Figure 124 – Radio Spurious Free Dynamic Range

 


MDS

Enter the inputs Temperature in Kelvin, Bandwidth in Hz, the Radio Noise Figure in dBF and the Radio Input Signal and Input Noise Level in dBm and Press Calculate to compute and display. Clear to reset and reenter value to retry and Close to Quit.  The temperature defaults to 290K (room temp 27C) some of the other parameters such as bandwidth also default to help prevent errors in the calculation caused by blanks or zeros.

EVM conversion

Enter the Radio EVm performance in units of dB, V Ratio (or Linear), or percent and press the associated “Calculate” button and the other EVM formats are calculated.

 

Figure 125 – Radio Minimum Detectable Signal and EVM conversion

EVM_NF

This calculation used to calculate Noise Figure from the Receive Signal Level, the bandwidth of the measurement and the EVM of the radio. Enter the values and press Calculate and it will calculate the Noise Figure in dBF units.

 

Figure 126 – Radio EVM to NF conversion

 

 

Carrier to Noise or C/N

 

C/N <> Eb/No w/DataRate

Enter the inputs Eb/No (energy of data by Noise power) in dB, Bandwidth in Hz, the Radio Data Rate in MB/Sec and press Calculate to get the Carrier to Noise ratio in dB.  Clear to reset and reenter value to retry and Close to Quit.  The temperature defaults to 290K (room temp 27C) some of the other parameters such as bandwidth also default to help prevent errors in the calculation caused by blanks or zeros.

 

C/N<> RSL_NF_T_B

Enter the inputs Temperature in Kelvin, Bandwidth in Hz, the Radio Noise Figure in dBF and the Radio Input Signal in dBm and press “Calculate” to get the Carrier to Noise ratio in dB.  This function can be worked the other direction as well enter C/N and get RSL. Press “Clear” to clear the coefficients and begin over. Press the “Close” button to quit the screen and go back to main menu.  The temperature defaults to 290K (room temp 27C) some of the other parameters such as bandwidth also default to help prevent errors in the calculation caused by blanks or zeros.

 

Figure 127 – Radio Carrier/Noise Calculations

 


Cascade

Enter the inputs Input Power in dBm, and the Gain in dB, Noise Figure in dBF and Third Order Intermodulation in dBm of the stages in the Radio and press Calculate to get the Total Gain in dB, Total Noise Figure in dBF and Total Intermod dBm.  This function can be worked the other direction as well enter C/N and get RSL. Clear to reset and reenter value to retry and Close to Quit. 

Figure 128 – Radio Cascade Calculation

Antenna

Enter the Mid-Band Frequency of operation in MHz, the Loading Factor (capacitive end loading), the Length to Diameter ratio approximation and press “Calculate” to get the Antenna Factor and the Antenna Lengths for Quarter and Half Wavelengths in ft, cm and Meters.  Press Clear to clear the coefficients and begin over. Press the Close button to quit the screen and go back to main menu. 

 

Figure 129 - Radio Antenna Calculations

 


ERP

Enter the inputs of Transmitter Power in dBm, Transmitter (source) match in dB, System Return Loss (Noise Level) in dB, Antenna (Load) Match in dB and the Transmitter to Antenna Cable Loss in dB and press Calculate to get the Corrected Transmit Power dBm.  Add the variable for Antenna Gain and it computes the EIRP Effective Isotropic Radiated Power. Finally enter the Distance to receiver or measurement point and calculate the Power Density. Press Clear to clear the coefficients and begin over. Press the Close button to quit the screen and go back to main menu. 

Figure 130 – Radio Effective Radiated Power Calculations

Path Loss

Enter the frequency in MHz and the Distance to get the Path Loss for Isotropic Atmospheric Loss in dB. In addition, the user can input the Power Transmitted (Xmit) and the Power Received both in dBm. Press Calculate to get the Path Loss in dB for either or both calculations.  Clear to reset and reenter value to retry and Close to Quit.. 

 

Figure 131 – Radio Radiative Path Loss

Modulation

Modulation Index Specs

Enter any two values to compute the third. In this case a FM Carrier Deviation of 10KHz and an Modulating Signal Bandwidth of 3 KHz gives a Modulation Index of 3.333. Press Calculate to compute, Close to quit and Clear to clear the value to retry.

Figure 132 - Modulation Index Specs

FM Modulation Index

Enter any two values to compute the third. In this case a FM Carrier Deviation of 10KHz and an Modulating Signal Bandwidth of 3 KHz gives a Modulation Index of 3.333. Press Calculate to compute, Close to quit and Clear to clear the value to retry.

Figure 133 – Modulation FM Mod Index

FM Bandwidth to IF Bandwidth

Enter any two values to compute the third. In this case a FM Carrier Deviation of 200Hz and an IF Bandwidth of 5 KHz gives a Modulating frequency of 1150Hz. Press Calculate to compute, Close to quit and Clear to clear the value to retry.

Figure 134 – FM Bw to IF Bw