The Radio Message System enables the relief of radio traffic on busy radio frequency channels by the application of data short messages for routine messages.

After more than 20 years operation, the system has shown excellent performance in practical use in Germany.  Authorities and Organizations with Security Tasks (BOS) in Germany have a "Technical Directive" with an exact system description with which a standard data transfer procedure was developed.  This procedure was introduced and applied by the police, fire departments and their support organizations as signaling system between mobile radio subscribers and the stationary RT equipment.

The RMS enables a significant reduction in time of message exchanging in RT traffic circles between the mobile task forces and main control panel through the transmission of digital short telegrams instead of analogue speech for defined tactical messages and instructions. 

The Radio Message System starts the operation of automated computer operated main control panel that enables rapid overview of the mobile forces that are monitored by the main control panel and therefore increases the efficiency.

Due to the reduced occupation duration of respective RT channel, higher channel utilization is achieved for important calls.  According to the system concept, the Radio Message System meets the following requirements:

• sufficient transmission security,

• operability of the different types of relay traffic used by security authorities and

• various incoming paths (wiring, line-of-sight radio links and carrier frequency routes),

• utilization with the introduced and standardized RT installations according to the

• BOS technical directive without interfering in the equipment,

• compatibility of RMS additional equipment of different manufacturers according

• to the technical directives.

2.  System Structure

According to the various tactical requirements of the BOS, the Radio Message System works with additional equipment on the RT installations on the stationary and mobile side.

2.1 RMS Main Control Unit

Each RMS main control panel unit must be able to correspond with RMS vehicle equipment.

Depending on requirement, incoming telegrams will be acknowledged automatically.  The generator releases selective addressed telegrams for the transmission of remote orders (instructions or remote data).  The discrimination of incoming and outgoing telegrams is ensured by direction identification.

2.2 RMS Vehicle Equipment

Status and identification generator on the subscriber's mobile RT set enables coded messages to be transmitted to evaluator of the main control panel, which are routed on to main control computer for further processing after being checked for faultlessness.  Optical and acoustic signals indicate the recognition of fault-free signal traffic.

3.  Types of Transmission

3.1.  Status Message

Status message generator enables the mobile RMS equipment to transmit messages to the stationary RT equipment.

3.2  Reception of Remote Orders (Construction Phase II)

In addition, the vehicle RT units incorporate an evaluator for incoming telegrams.  Correct identified telegrams are, depending on receipt requirement, acknowledged automatically.  In general, the mobile RMS equipment expects a receipt telegram for outgoing telegrams.  If a receipt is not received from the stationary main control panel then telegram transmission will be repeated automatically.

3.3  Sequence Telegram Transmission

For future applications, RADIODATA RMS vehicle units are suitable for the transmission of sequence telegrams according to the BOS technical directive.  With this, e.g. coded location messages can be transmitted from the vehicle units or if necessary can be inquired by the main control panel.

3.4  RMS Short Text Transmission

In text transmission mode, a maximum of 99 characters in a chain of sequence telegrams can be sent from the stationary side to mobile side.