Re: Re[4]: [smartBridges] SimpleNMS UPDATE Please

Earl Campbell Thu, 28 Aug 2003 16:33:53 +0000

MMMMM....your right. I did this analysis via Electrocomm's site. Think the SimpleNMS is lying. (others have pointed this out)

Earl - UpHi.net

Wireless Network Link Analysis Results

[link view]

 Highest transmitted frequency : 2483.000 MHz (2.483 GHz) 
                    Wavelength : 4.753 inches (12.074 centimeters) 
   Transmitter RF power output : 20.000 dBm (100.000 milliwatts)

            Transmit cable type : Times Microwave LMR-600
          Transmit cable length : 1.000 feet (0.305 meters)
      Total transmit cable loss : 0.044 dB (0.044 dB/foot 0.145 dB/meter) 
  Total transmit connector loss : 0.500 dB through 2 connectors 
      Total transmit cable loss : 0.544 dB 
  Transmit miscellaneous losses : 1.000 dB 


     Transmit antenna peak gain : 2.2 dBi 
  RF input power to the antenna : 19.456 dBm (88.227 milliwatts)  
 Allowed input power to antenna : 30.000 dBm (1000.000 milliwatts)   Per FCC Part 15 rules
        Transmit antenna height : 60.000 feet (18.288 meters)
  Distance to the radio horizon : 10.629 miles (17.106 kilometers)

             Receive cable type : Times Microwave LMR-400
           Receive cable length : 1.000 feet (0.305 meters)
       Total receive cable loss : 0.067 dB (0.067 dB/foot 0.221 dB/meter) 
   Total receive connector loss : 0.500 dB through 2 connectors 
       Total receive cable loss : 0.567 dB 
   Receive miscellaneous losses : 1.000 dB 


      Receive antenna peak gain : 15 dBi 
         Receive antenna height : 60.000 feet (18.288 meters)
  Distance to the radio horizon : 10.629 miles (17.106 kilometers)

           Received power level : -34.941 dBm (4003.316 �V) 
           Receiver's threshold : -82.000 dBm (17.762 �V) 
            Thermal fade margin : 47.059 dB    Just down the block, Huh.
          Probability of outage : 0.001 % 
     Total free space path loss : 70.030 dBi over a path length of 0.019 miles (0.030 kilometers) 
          Peak transmitted EIRP : 20.656 dBm (116.303 mW)

           Midpoint 0.6 Fresnel zone boundary : 2.437 feet (0.743 meters)
   Maximum space wave communications distance : 21.258 miles (34.212 kilometers)

Radio horizon data is for 4/3 Earth, k = 1.33.
All cables, antennas, connectors, and adapters have a 50 ohm impedance.
Receive and threshold voltages are for a 50 ohm load impedance and don't take into account the receiver's bandwidth or temperature.
Horizontal polarization will generally provide less multipath in urban areas and may provide lower path loss in non line-of-sight situations.
Attenuation from trees is approximately 0.35 dB/meter at 2.4 GHz.  At lower frequencies, the attenuation is somewhat lower for horizontal polarization than for vertical, but the difference disappears above about 1 GHz.
Attenuation of a 2.4 GHz signal in heavy rain (150 mm/hr) is 0.02 dB/km.
Assumes 0.25 dB loss for each coax connector or adapter.
Use as much antenna gain as possible, and get your antenna as high as possible.
Maximum space wave communications distance is the longest distance possible using the choosen antenna heights.  It does not mean a link that long is possible.
Try to obtain a thermal fade margin of 20 dB, or larger, for a more reliable link.  If the fade margin is negative, that link is impossible.

Calculated on Thu Aug 28 16:25:55 2003 GMT

-------Original Message-------

From: [EMAIL PROTECTED]

Date: Thursday, August 28, 2003 10:50:11 AM

To: [EMAIL PROTECTED]

Subject: Re[4]: [smartBridges] SimpleNMS UPDATE Please

Earl,

900+ -> 100 ft(31m),Tx_20dBm,Ant_2.2dbi

SB API -> Ant_15dbi

Theoretically MAX_from_900+ :

Rx_SB_API = -100 -20Log(0.031) +2.2 +20 +15 = -33dBm

Practically MAX_from_900+ :