ADTRAN 6000 Series system manual Path Loss LP, LP = 96.6 + 20 ⋅ log10d + 20·log10f

Section 2 Microwave Path Engineering Basics TRACER 6000 Series Integrated System Manual

Path Loss (LP)

Path loss is the estimated attenuation between the transmit and receive antennas caused by signal separation and scattering. The path loss is considered basic transmission loss over the microwave link. The following expression calculates path loss:

L		= 20 ⋅ log⎛	4πd	(dB)
	P		---------⎞
		⎝	λ ⎠

where

fcarrier frequency (Hz)

λcarrier wavelength (c / f) (meters) d path distance (meters)

c speed of light, free-space (meters)

or
LP = 96.6 + 20 ⋅ log10(d) + 20·log10(f)	(dB)
where d is expressed in miles and f in GHz.

Path loss, as shown here, increases rapidly as either the path length increases or the carrier wavelength decreases (which happens as the carrier frequency increases). Therefore, longer microwave paths naturally experience more path loss than shorter paths. Likewise, higher frequency microwave communication experiences more path loss than lower frequency microwave communication.

The path loss values for various path lengths for the TRACER 64x0 2.4 and 5.8 GHz systems are listed in Table 7 (miles) and Table 8 on page 23 (kilometers).Values not listed in the tables can be interpolated from those listed.

Table 7. Path Loss for Given Path Lengths (miles)

Path Length	Path Loss (dB)	Path Loss (dB)
(miles)	at 2.4 GHz	at 5.8 GHz
1	104	112
2	110	118
3	114	121
4	116	124
5	118	126
10	124	132
15	128	135
20	130	138
25	132	140
30	134	141
35	135	143

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