PRODUCT OVERVIEW
Principles of operation
2.10
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19.01.2007
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2.3
Principles of operation
2.3.1 DECT Network Entities
HW 86012 employs radio transmission according to the international DECT standard on 1.9
GHz. It is compliant with the air interface standard EN 300 175. HW 86022 uses a modified
version of that standard which is compliant with FCC part 15 and EN 300 328 for DECT
operation on 2.4 GHz ISM band. The following description applies to both systems.
The DECT standard defines two communication entities: The fixed termination (FT),
commonly seen as base station, and the portable termination (PT), usually a handset.
Throughout this manual the terms “fixed” and “portable” are used in the DECT sense. This
does not preclude that a FT may change its location or a PT may be stationary mounted.
A HW 86012/22 can be configured either as PT or as FT. For the most simple case, a point-
to-point connection between two modules, one side must be configured as PT and the other
side as FT
The general architecture of any DECT system comprises one FT and a variable number of
PTs. This is called a point-to-multipoint network. The number of PTs in a network is not
limited by the DECT standard but only by implementation constraints.
Larger DECT networks often include multiple “base stations”. Strictly speaking, the DECT
network still has a single FT but this is distributed on multiple cells. Many people get
confused about that concept, because they associate “base station” and FT. Within DECT
terminology the term “base station” is not used at all, but this entity is called a “radio fixed
part” (RFP). So in any DECT system there is one FT which comprises one or multiple RFPs.
All entities are identified by DECT-internal “addresses” (for a more detailed discussion on
DECT identifiers see section 3.2.1). When installing a DECT system, every PT must learn
the identity of the FT and the FT must learn the identities of each PT. This procedure is
called subscription. Subscription defines which PTs belong to a FT. All DECT security
features (authentication and encryption) build on that mechanism. The subscription
procedure for HW 86012/22 is described in sections 3.2.3 and 3.2.4.