SmartBridges sB3010 ユーザーズマニュアル

 

 

 

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airHaul™ Nexus User Guide

 

Link Budget Planning is a very useful tool for link budget estimation. The Link Budget Planning 
Calculator can be accessed from the navigation menu bar ’Tools| Link Budget Planning Calculator’ 
drop down menu. 
 
A GPS Calculator is provided in the Link Budget Planning Calculator page to calculate the distance 
between two airHaul stations.  To calculate the distance, follow the steps below: 

1.  Enter the GPS co-ordinates of Station 1 (Latitude 1 and Longitude1) and Station 2 (Latitude 2 

and Longitude 2). GPS co-ordinates may be entered in DD: MM:MM or DD: MM: SS.SS 
formats. 

 
2.  Select the distance units (miles or kilometers). 
 
3. Click 

the 

’Compute Distance’ button. 

 
4.  The distance between the two stations will be displayed in the Distance box as in Figure 7-9. 

 

 
Once the distance is computed, user can do the link budget calculations as follows: 

 

1.  Select the radio mode for station 1 and 2. 
 
2.  Enter the transmit output power in dBm for station 1 and 2. 
 
3.  Enter the antenna Gain in dB for station 1 and 2. 
 
4.  Enter the Cable Losses in dB for station 1 and 2. 
 
5. Click 

the 

’Compute Link Budget’ button to calculate the link budget information. 

 
6.  The link budget information will be displayed as in Figure 7-10. 

   
The link budget information EIRP, Free Space Loss and Theoretical RSSI are computed and 
displayed.  
 
The Receive Sensitivity, Maximum Transmit Power, System Gain and Available Fade Margin at 
various Link Speeds are also computed and displayed in a table. 
 
Ideal fade margin for a link is between 10 dB to 20 dB for a stable link base on the environmental 
condition of a region.   
 
Fresnel Zone Clearance Required will also be displayed.