25dB - izlazna snaga
27dB - pojacanje antene
-137dB - slabljenje na 30km
to bi bilo: 25+27+27-137=-58dB (u idealnim uslovima, ako na oba kraja stavis AirGrid 27dB).
Ja imam Nanostation Loco M5 i AirGrid 27 za link od kilometar ipo - na 5GHz kroz drvo :( - ne postoji opticka vidljivost, ali signal ne pada ispod -63dB - trenutno je -57dB - drvo unistava signal dobro (i to izlazna snaga nije ni blizu 25dB).
Sa ovim signalom rate iako je na auto ne pada ispod 135Mbit, a realan protok je 9 - 9.5MB/s - a ping evo:
XM.v5.3.2# ping 192.168.2.10 -c 4 -c 10
PING 192.168.2.10 (192.168.2.10): 56 data bytes
64 bytes from 192.168.2.10: seq=0 ttl=64 time=1.152 ms
64 bytes from 192.168.2.10: seq=1 ttl=64 time=0.749 ms
64 bytes from 192.168.2.10: seq=2 ttl=64 time=0.721 ms
64 bytes from 192.168.2.10: seq=3 ttl=64 time=0.879 ms
64 bytes from 192.168.2.10: seq=4 ttl=64 time=0.721 ms
64 bytes from 192.168.2.10: seq=5 ttl=64 time=0.695 ms
64 bytes from 192.168.2.10: seq=6 ttl=64 time=0.954 ms
64 bytes from 192.168.2.10: seq=7 ttl=64 time=1.154 ms
64 bytes from 192.168.2.10: seq=8 ttl=64 time=0.700 ms
64 bytes from 192.168.2.10: seq=9 ttl=64 time=0.717 ms
--- 192.168.2.10 ping statistics ---
10 packets transmitted, 10 packets received, 0% packet loss
round-trip min/avg/max = 0.695/0.844/1.154 ms
Cak i da izguras -70dB - mada mora da bude u granicama do -60dB signal, radice bar MCS4 ili MCS5 sto je 90ak Mbps rate - ili realno bar 50Mbps protoka.
Samo ako postoji vidljivost, nema razloga da ne radi.
Ja sam bio skeptican povodom ovog linka na 5GHz kroz drvo, ipak je ludost 5GHz bez opticke vidljivosti, ali radi.
Čemu ovo služi, a uz to i ne radi?!?!?!?!
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result/3821970146