Coaxial Loss Calculator
Do you know that you lose 4G /5G signal in coax cables between the antennas and the router?
The result is decreased speed, range and reliability. Good news are you can avoid most of that loss by using less cables and keeping those as short as possible.
(mid-range 4G)
(urban 4G)
(between below deck router and antennas on the mast)
***The loss calculation in red is based on an LMR400 (most common cable used for such installs) incl. insertion loss of 4 connections; at frequency 3400 MHz. See more details below.
Coaxial loss with a typical Pepwave installation:Classic setup, below deck router, antennas on the mast:
5 chunks of coax cable in use; all different type.
Loss occurs in 1) mast cable, 2) pigtail router to mast cable, 3) pigtail mast cable to antenna, 4) cable inside router, 5) cable inside antenna. Additional loss occurs in multiple junctions/ coax connectors accounting for approx. 10% each.
(mid range 4G)
(urban 4G)
(mid range 5G)
Coaxial loss with Meridian 5G all-in-one dome:There is only one 15cm cable connecting modem and antenna-circuit. No connectors, no insertion loss.
(mid range 4G)
(urban 4G)
(mid range 5G)
“Aftermarket” domes trying to put a Pepwave or Celerway routers inside a dome:
“Aftermarket” domes trying to put a pepwave or celerway routers inside a dome close to standard mast mounted antennas have 3 chunks of cable in use; all different type: 1) inside the router, modem to SMA connector, 2) pigtail connecting router’s SMA connector to antenna connector (SMA or N-type), 3) cable inside the antenna
(mid range 4G)
(urban 4G)
(mid range 5G)
How the above is calculated:
Submitting RF signals (EM waves) over Coax cables decreases signal power and signal quality.
Decrease of signal power, Attenuation or Loss, is measured in dB.
dB (Decibel) is a logarithmic unit of measurement.
Type/ Quality of the coax cable(s) are the key factors, as well as the number of junctions.
Every single coax connector increases power loss.
10dB loss equals 10% of original signal power remaining, equals 90% loss of signal power.
Formula – Loss “L” in dB:
L = -10*log(Po/Pr) | Po: output power; Pr: reference power
Formula – Remaining Power “P” in %:
P = 10 ^(L/-10) | ^: powers
Decrease of signal quality (RSRQ, SNR) is related to the type of coax cables, as well as the number of different coax cable types in use.
Multiple junctions/coax connectors decrease signal quality significantly, due to insertion losses and signal reflection.
General rule:
Coax cables as short as possible.
Quality (mainly defined by diameter of the inner conductor) as good as possible.
Avoid multiple junctions/ coax connectors.
In a perfect world, the antenna circuits are connected to the modem with 1 single piece of cable, no connectors, cable soldered.