Stevens was recently engaged in a project to provide a wireless link for the NY/NJ Port Authority from their location in Jersey City to a off-site backup facility in western NJ, using a station on top of the Howe Center as a relay site for the first link and a tower in West Orange, NJ as a relay site for the second link. One approach considered was to operate the link in the 5 GHz ISM band. Here are some potential parameters for this option:
RF bandwidth: 11 MHz
Jersey City-Hoboken antenna gain: 24 dBi
Path length from Jersey City to Hoboken: 1.4 miles
Howe Center-Jersey City antenna gain: 24 dBi
Howe Center receiver noise figure: 6 dB
Howe Center-West Orange antenna gain: 33 dBi
Path length from Howe Center to West Orange: 12 miles
West Orange to Howe Center antenna gain: 26 dBi (lower due to tower mount)
West Orange receiver noise figure: 6 dB
Assuming a 24 dB link margin is needed to account for fading and loss due to heavy rainfall on the longest link, while 12 dB link margin is sufficient for the shorter link, what transmitter powers are needed at each of the four transmitters (JCHowe,Howe-JC, Howe-WO, WO-Howe)? Since this is a line-of-sight link,assume free space propagation loss.