Communication / LTE

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Updated – January 12, 2024

If you are not traveling in perfectly covered mobile phone regions, i.e. in an urban environment, but prefer quiet and idyllic areas, the question arises: Which equipment ensures a usable LTE connection option even in more remote places.

LTE directional antennas are generally ruled out because they require a constant and good alignment towards the transmission tower. A very good directional antenna (two pieces are always required, one for horizontal and one for vertical polarization) achieves up to 20 dBi.
Omnidirectional radiators are therefore the more viable choice, albeit with less gain/gain. Most – cheaper – omnidirectional antennas, provide a gain of around 2...6 dBi.

The currently most powerful omnidirectional antenna is the KASER 4G LTE with 12 dBi gain. The installation of this antenna on a mobile home is shown below.

Mounting the LTE antenna

The antenna is usually attached to an antenna mast using a tiltable angle plate and appropriate mast clamps. Apart from the fact that this type of installation seems strange on a caravan or motorhome roof, the installation height should not be overused. Therefore, the antenna, which was attached with four small Phillips screws, was first removed from the included angle plate.

The angle plate was cut cleanly flush with the antenna-side mounting plate using a cut-off grinder. The four antenna mounting screw holes were countersunk to allow the screw heads to be flush with the mounting plate.

In addition, four additional holes were made in the corners of the mounting plates, also countersunk from the opposite side, so that four screws for fastening could be inserted flush through the caravan/motorhome roof.

This modified mounting plate was then used as a drilling template on the roof.

Finally, the antenna was screwed back onto the mounting plate using the original screws. Four washers had to serve as spacers because by countersinking the screws they would now penetrate deeper into the base of the antenna than was possible with the specified drill hole depth.

The two antenna cables were now routed through the holes previously made at a distance of 15 mm.

Silicone was applied to the mounting plate from below to achieve consistent watertightness around the holes in the roof membrane.
When tightening the approx. 60 mm long screws that reached under the roof structure, the mounting plate leaked silicone all around. This was roughly removed.

Cover of the mounting plate

A cable duct cover approximately 100 mm wide and approximately 20 cm long was provided with a 60 mm hole for the antenna housing. The underside was generously filled with silicone, guided from above over the antenna down to the roof and pressed down. Excess silicone was roughly removed again. The finish was done using dish soap on the finger and carefully smoothing the silicone seam.

In this way, the antenna is mounted solidly and completely wind and waterproof.

The preferred location (for right-hand traffic) is the driver's side, as the tunnels/underpasses that pass through are highest here. The antenna should be mounted away from the satellite dish or other metal structures.

LTE router / Telephony

Only a powerful router completes the LTE system and provides Internet and telephony as well as SMS/MMS services.

It should be noted that the router supports the LTE bands prevailing in the respective country. Furthermore, the sensitivity of the LTE modem and of course the presence of external antenna connections are of fundamental importance.

An example of an LTE router that satisfies the above-mentioned concerns is: Huawei B618s-22d, which also offers CAT11 with 600 MBit/s download, 50 MBit/s upload and WLAN with up to 867 MBit/s.

In addition to a WAN and LAN connection, the router also provides a telephone connection. Here you can use a DECT base such as: Gigaset BOX 100 be connected. Hands-free calling and listening can be done comfortably with the Gigaset T480HX with display and AB function. Any DECT handset expands the system to include additional handsets.

The LTE router should ideally be placed near a window so that the emission from the WLAN antennas can also be used outside the vehicle. An aluminum outer skin weakens the WiFi signal considerably.
If the router has to be installed in unfavorable locations, an external access point may still have to be installed.

Video surveillance

If video surveillance is to be installed on all four corners of the vehicle, the use of POE-powered PTZ cameras and thus the use of an administrable switch, such as 8-port POE, is recommended Ubiquiti US-8-150W or Ubiquiti US-8-60W with 4 POE and another 4 LAN ports required.

For this purpose it is recommended, for example: the PTZ dome camera Hikvision DS-2DE2A404IW-DE3 (2.8-12MM). There is more on this topic here to read.

The video streams can be played back via cell phone or tablet using the very inexpensive (iOS) app IP CamViewer which also enables PTZ operation.

The Hikvision mount is ideal for mounting DS-1294ZJ at.

Power supply to the components

It would be nice if all of the aforementioned devices could be operated with a 12 V on-board voltage. Yes, far from it. So what do you do if you need 6.7 V for the Gigaset components, 5 V for a Raspberry Pi, etc.?

Either adjustable or fixed voltage regulators are available for this.
For example, this is suitable for 6.7 V Kemo M015N, which delivers 1.5 A and can be adjusted from 3 to 15 V (continuously), with input voltages between 6 to 28 V.
This delivers 5 V 15 A DC-DC step-down converter with an input voltage range of 12 .. 24 V. This can be used to supply plenty of USB sockets for charging various cell phones, tablets, etc.

What all voltage converters have in common is that they generate heat loss and require appropriate cooling if the Lqst is correspondingly high. This can be done, for example, by screwing it on Finned heat sink take place. Please note that a thin layer of thermal paste is applied between the contact surfaces. The devices should have full contact with the heat sink with their cooling surface and be attached to it with a suitable screw fastening.