free space path loss

[loai khader]

please I AM NEED help

i need solution for question
for MW system the carrier freqency use 6G Hz and distance between two ends of Mw link is 50 km
find
1- free space path loss (db)
2- for using gain system antenna if transmitted power sidnal is 1000 W what would be the signal level in dB at the reciver

 

[RealAEL]

Without knowing the Tx and Rx antenna gains that is difficult to know but at a very simple level and assuming ideal omnidirectional antennas (0 dbi gain) it would be -82 dB.

Path Loss in free space

Signal level is not measure in dB, but again using simple assumptions, Tx power of 1000W is 60 dBm so again ignoring antenna performance Rx signal would be (60 - 82) dBm = -22 dBm (6.3 uW).

 

[N.Narayanan]

Use given formula to calculate the free space path loss in dB,

FSPL (dB) = 20 log10 (d) + 20 log10 (f) + 32.44
Where:
d is the distance of the receiver from the transmitter (km)
f is the signal frequency (MHz)