DECT telephony

Single or multi-cell, that is often the question!

The DECT standard

DECT cordless telephones in buildings, warehouses or even outdoor areas for which the GSM mobile network is not an option (e.g. for cost reasons or network coverage) mostly use the DECT standard. DECT (Digital Enhanced Cordless Telecommunications) offers a number of advantages and has long since prevailed in Europe over other standards (such as GSM) in telephony.

DECT does not interfere with other networks, for example, due to the frequency band used from 1880 to 1900 MHz. At the same time, however, there is enough bandwidth available to transmit speech without interruption and in the best audio quality.

In addition to pure voice transmission, the DECT standard can also exchange data between handsets and base stations. For example, it enables access to external telephone directories.

DECT is also well equipped in terms of eavesdropping security. Unauthorised access is made doubly difficult: On the one hand, new devices and subscribers must be registered at the base station, whereby they receive a clearly traceable registration. On the other hand, the handsets must authenticate themselves with a secret key at the base station each time a call is set up.

For whom does a single-cell fit

DECT single-cell networks are now widespread and are often found in private homes. Their advantages are obvious: the DECT base is easy to set up and usually offers enough range to completely cover a flat. However, if this is not enough, inexpensive repeaters provide a remedy. The greatest benefit, however, is certainly mobility, which hardly any user in today's private environment would want to do without.

The situation is somewhat different in the business environment, where stationary desk phones are still very often used on desks. Nevertheless, there are also enough applications here for which mobile devices are recommended - from the IT administrator who is constantly on the move to the nurse, the doctor or even the warehouse clerk. In all these fields of activity, mobile means of communication are needed - and this should preferably not include the private mobile phone.

However, offices, hospitals or warehouses place completely different demands on modern DECT telephony, as it is often necessary to cover large, possibly winding areas with DECT. This is because real-time communication plays a decisive role, especially in business and medical environments. Calls must be able to be made at any time and virtually anywhere - and as efficiently as possible and without cumbersome operation.

Especially in sensitive environments, such as hospitals, schools or danger zones, this high availability is an absolute must. This can only be covered in the rarest of cases by a single-cell base, whose equipment naturally reaches its limits. The use of a multi-cell solution is the optimal solution here.

A multi-cell is a network of several base stations within a building or an open area. These are positioned in such a way that the effective circles of the individual radio cells (DECT bases) overlap. This not only guarantees area-wide availability, but also allows the subscriber making the call to move freely between the individual base stations without the call being interrupted ("seamless handover"). This is made possible by a DECT manager integrated in each base station, which transfers the telephone call to the next base station with the best reception performance to the handset without interruption.

Learn more about possible applications of DECT solutions in our work environment overview.

For a multi-cell solution, some basic requirements must be observed:

• You need a network connection at each place of use of a DECT base, preferably with PoE.
• Your network switches should be dimensioned according to the PoE classes of the DECT bases and supply sufficient power.
• For optimal placement of the bases you should carry out a so-called illumination. Snom partners can borrow a 
  Radio DECT Measuring Kit from us for this purpose.

Once the DECT network has been set up and the corresponding bases and handsets have been provisioned, the system largely manages itself. Necessary updates are also distributed to the connected handsets via a wireless DECT data connection (OTA). This eliminates almost all administrative effort after installation - even for very demanding projects.

Does it have to be a multi-cell or is a single-cell sufficient?

Whether single-cell or multi-cell is mainly decided by the type of use and the size of the installation itself.