Rumus Path loss (Theodore, 1997: 116-122).

Rumus Path loss (Theodore, 1997: 116-122).

Afs = 92,4 + 20logd + 20logf            

Apabila:

d adalah nilai jarak (km)  = 6,54 km

f adalah frekuensi (GHz)  = 7 GHz

Rec. Thresh old 10⁻⁴ = Lthresh  = -88 dB

Rec. Thresh old 10⁻⁶ = Lthresh = -84 dB

Antena gain = Gantena = 30,5 dBi

Standar output power untuk microwave tipe 7 GHz = 21 dB

Maka:

Afs = 92,4 + 20 log 6,54 + 20 log                                                 

mencari perhitungan link budget

terhadap microwave, sebagai berikut:

Lrx = Ltx + 2Gant – 2Afeeder – Afs

M = Lrx – L thes                                                                  

Keterangan:

Lrx = received power (dBm)

Ltx = transmitted power (dBm)

L thesh = received threshd (dBm)

M = margin

Gant = antenna gain

A feeder = feede cable loss M10  ̃3

= Lrx – Lthresh = -125,6 – (-88) = 37,6 dB M10  ̃6

= Lrx – Lthresh = -125,6 – (-84) = 41,6 dB

Maka:

Lrx = Ltx + 2Gant – 2Afeeder – Afs

      = 21 + 2x30,5 – 2x3 – 125,6

      =21 + 61 – 6 –125,6

      = -49,6 d