Mimer RadioServer
When you need to access your devices from several WAN or Internet based dispatchers.
The RadioServer will manage multiple TCP connections for you.
The RadioServer expands your system so that operators can be placed at different sites all around the world. The special satellite version also helps with the jitter that sat-links experience.
Using the RadioServer
The Mimer RadioServer is needed in larger systems were TCP is used (usually when running over the Internet). A Mimer Network Interface can handle just one TCP-connected dispatcher PC at a time. (In local systems using UDP to connect, you can have many operators without a server)
The RadioServer solves this limitation. By installing a Mimer RadioServer at the base station site, multiple TCP-connected dispatchers can share each device.
The server can also be installed at a dispatcher central to distribute radio resources to other dispatchers over the Internet.
This is perfect when you have for example a taxi company with local dispatchers during the day and remote dispatchers at night. Or you have dispatchers that need to work from home.
Technical
The Mimer RadioServer Mk3 has a capacity of 256 connections each configurable for radio or dispatcher. Like this:
- 2 radios x 128 operators
- 4 radios x 64 operators
- 8 radios x 32 operators
- 16 radios x 16 operators
- 32 radios x 8 operators
- 64 radios x 4 operators
- 128 radios x 2 operators
The Mimer RadioServer Mk3 is delivered as a self contained small Linux computer running on 12VDC. It will start by itself if there has been a power failure. It has low power consumption and is easy to install also with power back up.
Due to delivery shortage of PC components, the RadioServer might also be delivered in an alternative hardware. It meets all the same demands as the standard hardware.
Virtual RadioServer
Mimer RadioServer is, as standard, delivered pre-installed on a SolidStateDisk mounted in a compact industrial x86-64 computer, as described above.
However some customers prefer to run the RadioServer on a hardware platform they are used to. The RadioServer can therefore also be delivered as a VDMK-file to be run on a virtual computer using Oracle Virtual Box or VMWARE. The virtual disk file contains a preinstalled 64bit Debian 11.5 OS.
The current virtual machine file has been created and tested using Virtual Box version 6.1. Recommended specifications for the virtual machine can be found on the FAQ page.
Additionally, we have .deb installation package files available built for Debian 11.5 and Ubuntu 20.04. These installation packages do not install a web server but include the necessary files for hosting the web-based status and admin configuration panel with your webserver of choice. The web interface is written for PHP 7 and to get full functionality your webserver needs to support reverse-proxy.
A sample web server configuration file for lighttpd is also included in the files installed by the installation package.
Mimer RadioServer Mk3
Dimensions:
200x120x50mm, plus connectors
1050grams
Power:
Runs on 12VDC, 3,5A, through
an adaptor that needs 100-240VAC
Alternative housing for the Mk3 RadioServer
Technical Issues
We gather technical questions and answers on this page!
Setup instructions can be downloaded from the technical download page.
The old Mk2 version of the RadioServer
RadioServer Satellite Version
Takes care of high latency and high jitter.
Already in the standard version of the Mimer RadioServer, much higher levels of latency and jitter can be handled than in the standalone Network Interface.
For connections with extra demands there is also a special version of the RadioServer that improves this even more. Recommended for users with Satellite connections! If you are using an encrypted VPN tunnel over satellite, you must have the satellite version.
Windows has an “improvement” that causes problems for connections with a long delay, called “TCP Slowstart”. Sat providers usually can implement something called “TCP Spoofing” to counteract that, but if you have an encrypted VPN they cannot do that, and then you once again get broken audio. The solution is to use the Radio Server in Satellite mode together with the Network Repeater.
The satellite version of the RadioServer uses UDP Unicast for the communication, for this reason you always need a Mimer NetworkRepeater at the dispatch end. Please see drawings below.
Update regarding Starlink
A number of our customers have started to use Starlink instead of the traditional satellite service providers. All reports a very good connection with much improved connection speeds. And so far when using Starlink, the Satellite mode RadioServer has not been needed.
RadioServer – Web browser setup
Web browser setup menu
The Mimer RadioServer has a web browser based setup interface.
All settings of connected radios, IP addresses etc are easily done through a standard web browser. You can also change name, password etc.
There is also a list of previous settings so that it easy to revert to an earlier state.
RadioServer – Web browser status window
Web browser status window
The Mimer RadioServer has a web browser function were you can connect and see the status of the server.
You just need to browse the IP of the server and it will give you information on connected radios and connected operators.
It will also show what radios the operator is monitoring and if the operator is transmitting.
No changes can be made to the server from this interface, it is “look only”.
RadioServer / NetworkRepeater
In some cases a NetworkRepeater is the correct choice and not the RadioServer. In other cases you even need a combination of both. When using the satellite version, you always need a NetworkRepeater on the land side.
Read about the NetworkRepeater here.
Download a description off the differences between Mimer RadioServer and Mimer NetworkRepeater from the Technical Download Page.
System Examples
Showing some different examples where a RadioServer in needed.
Connection with a Mimer RadioServer at the base station site.
The server can handle one or many radios at the same site and many dispatchers at different places.
Showing two of the radios connection through UDP to the RadioServer and two of the operators connection through TCP to the RadioServer.
Example with several police stations with their own small systems. They are also connected together through their own WAN. With help of the RadioServers, operators at other police stations can remotely connect to each others radios.
In this case for operating a remote Tetra radio in DMO if the Tetra net does not function.
System Examples over satellite
Showing an example where a satellite version RadioServer is needed.
Connecting radios ofshore through a satellite link with the help of a Mimer RadioServer .
Showing how the ofshore equipment connect with UDP Unicast to the onshore equipment.