The INDeX DECT is a digital cordless telephony system for connection to the INDeX range of systems. The system allows users to make and receive INDeX calls with the freedom to move around the office or company site. INDeX DECT comprises three elements; DH1 Cordless Handsets, DECT Base Stations (DBS) and the DECT Control Unit (DCU).

Each DBS provides an area of radio coverage called a cell. Normally several DBSs are deployed at different locations to provide complete radio coverage for the customer's premises. Typically each DBS has a range of 60 to 600 metres depending on the building construction. The DCU performs the function of an intelligent interface between the INDeX system and the DBS. The user of a DH1 can make and receive calls anywhere within range of a DBS, up to 16 of which can be supported on INDeX. The system also supports up to 64 DH1 handsets.

As its name suggests, INDeX DECT uses technology compliant with the global DECT (Digital Enhanced Cordless Telephony) standard for digital cordless telephony. This means that, in addition to enjoying the high quality of digital speech, calls to and from a DH1 are entirely secure and cannot be monitored or overheard. The INDeX DECT also supports the features of roaming and seamless handover for DH1 users:-
Roaming is the ability to make and receive calls when moving between the radio coverage areas of different DBSs.
Seamless handover is the ability to move between the coverage areas of different DBSs during a call the user is not aware of the handover because there is no change to speech quality.
INDeX DECT is also compliant to the GAP (Generic Access Profile) standard. This is designed to allow the interoperability of DECT products from different manufacturers. Currently most DECT products are not GAP compatible. However with the development of cordless telephony, the marketplace will demand this compatibility.
INDeX DECT can also be used with most other telephone systems that provide analogue extension ports supporting DTMF or loop dialling and timed-break recall.

DECT Analogue Board (DAB) 
The DAB boards contain 8 circuits for connection to two wire ports on INDeX. These support MF or pulse dialling and Time Break Recall. A version of the PABX interface board with earth recall is also available, however this is not required for use with INDeX. 
Each cordless handset that is to be registered for use on the system requires a two wire analogue connection through the host PABX. The cordless handset provides the same functionality as a Plain Ordinary Telephone (POT) connected to the two wire port of INDeX, with the exception of message waiting indication. 

DECT Expansion Board (DEB) 
The DEB is an optional board fitted within the DCU providing support for a further 8 DECT Base Stations (DBS). 

DECT Base Stations (DBS) 
The DBS is a radio base station specifically for the INDeX DECT DCU solution. It has the same physical characteristics as the CSLC-DBS, but is only compatible with the DCU. 

Configuration Details 
The DCU interfaces directly to analogue extensions on the INDeX switching platform on a 'one port per handset' basis. Base Stations connect to the DCU and are supported up to to 1km distance, enabling a 2km radius to be achieved excluding the coverage area of each base station. 

DECT Repeater (Cordless Base Station) 
The coverage offered by the DECT Base Station can sometimes be limited by the ability to run cables to remote areas. The introduction of the DECT Repeater Base Station allows the area covered by DECT to be increased without the need to lay more cables.

The Repeater Base Station is able to offer an extension to the area serviced by the INDeX DECT system in a simple and cost effective manner.

The Repeater Base Station design is very compact (dimensions W x H x D are 150mm x 80mm x 35mm) and may be installed out of sight within false ceilings. The power is provided to the Repeater Base Station via an external mains adapter.

When the Repeater Base Station is used in conjunction with an External Antenna, the distance between the standard Base Station and the Repeater Base Station can be extended. The External Antenna is able to project the DECT signal up to 1000m back to the Standard DBS, allowing remote areas to be covered by INDeX DECT.

As with the standard DECT Base Station, the Repeater Base Station offers seamless handover and roaming support enabling users to move freely between cells during calls over an extended area.

DECT Deployment 
The essential element for a successful implementation of any cordless solution is the radio survey to determine the optimum positioning of the Base Stations to provide the desired coverage. The INDeX DECT Survey Kit was introduced to provide a compact tool that had been designed specifically for radio surveys for INDeX DECT.

The DECT Survey Tool consists of:-

Deployment Base Station (and associated PSU) 
Lucent DH2 or Deployment Handset 
Charger (and associated PSU) 
Survey Instructions

All the above contents are contained in a compact case. DECT surveys are simple but essential to achieve a successful DECT installation. 

Call Routing to INDeX DECT
Given the degree of integration available to cordless users with INDeX DECT, there are a variety of means by which calls can be routed to DH1 cordless handsets.

Since each cordless handset is effectively connected to INDeX via an analogue extension port, each also attracts an individual directory extension number to which DDI calls may be directed

Operator Transfer
Calls may be transferred to DH1 extensions by operators or other extension users

Group Working
DH1 handsets may be programmed as members of multiple and/or overlapping groups and attract calls in the same manner as any other INDeX extension within that group.

Divert Destination
Users may initiate any or all diverts from a DT extension to an INDeX DECT DH1 handset. This is particularly useful for extension users who are desk-based most of the time and want access to the full range of features available to DT extension users, but who need to be accessed quickly and efficiently when roaming on site. The ability to further divert calls from a DH1 to Voice Mail, combined with the enhanced divert facility launched on INDeX level 6.1 software (where "Chain Diverts" are supported), means that callers are efficiently diverted to the correct mail box in the event the DH1 user is no longer available to receive calls.

DH-1 Cordless Handset
The DH1 is the cordless handset for use with INDeX DECT. It is lightweight and pocket size (dimension 150 x 46 x 20mm) and weighs less than 135gms. The standard Nickel Hydride (NIMH) battery provides 9 hours talk time and 90 hours standby time. NIMH battery technology has the advantage of having no memory effect compared to traditional NiCad batteries.

The DH1 has access to all INDeX system features available to 2-wire ALOG extension ports (except receipt of message waiting). These system features include system speed dials, pick-up, park, hold & transfer and call diverts.

The DH1 can support the connection of a headset via the adaptor cord (the GN Netcom Profile I/II/III and ADDvantage ranges are recommended). The following functions are also provided by the DH1:

Large LCD display
Keys for display (menu, scroll & enter)
Headset connection (GN Netcom)
Redial feature
Integral belt clip
Keys for volume control & off-hook
10 tone ringer options
10 abbreviated number stores
Keypad lock
Auto answer (for use with headset)

The DECT Control Unit allows the programmed names or extension number of each DH1 to be displayed between DH1 users. Standby text may also be programmed for each DH1 to display the company name, extension number or the users name when the DH1 is idle.
The mechanisms for routing calls to DH1 handsets are outlined later in this section (see "Call Routing to INDeX DECT").

DH1 Charging Options
There is a choice of charging options for the DH1. For convenient personal use, a desktop charger for a single DH1 handset is available which also has a fast charge slot for a spare battery. There is also a wall or desk mount charger rack for 4 DH1 handsets, ideal for group usage. Both options are supplied with plug top power supply unit.

Lucent DH2 Cordless Handsets 
The Lucent DECT handset (DH2) is lightweight and pocket size (dimension 150mm x 46mm x 20mm), weighing less than 135gms. It comes with 9 hours talk time and 90 hours stand by time.

The Lucent DH2 is compatible with all the integrated features including access to both the internal and external INDeX Directory.

The handset provides calling or called party information based on the INDeX directory, for example, if ABC Services has a speed dial entry within the Lucent DH2 will display 'ABC Services' on receiving an incoming call. All directory numbers or names within a network of INDeXs will also be displayed when connected.

These enhanced features are not the limit of the functionality, the Lucent DH2 has access to telephone system facilities through feature codes in the same way as analogue telephones. These system features include system speed dials, pick-up, park, hold & transfer and call diverts.

The Lucent DH2 includes a vibrating handset option as standard. The handset may be set to ring, ring and vibrate or simply vibrate and is easily selected by a clear and concise menu structure. This allows cordless users to select the ringing option based on there requirements, for example if the user is in a meeting they may not wish to disturb the meeting and set their phone to the vibrate only option.

INDeX DECT Handset features include:-
Large LCD display 
Keys for display (menu, scroll & enter) 
Keys for volume control & off-hook 
Redial feature 
Keypad lock 
10 tone ringer options 
10 abbreviated number stores on the handset 
Headset connection 
Integral belt clip

Handset accessories include:-
A desktop charger for single handset.
A desktop charger for a single handset with a fast charge slot for a spare battery.
A desk standing or optionally wall mounted 4 way multi-charger for environments where multiple handsets maybe deployed.
A headset adaptor cord for use with the recommended GN Netcom ADDvantage range of headsets.
Handset holster may be used in physically harsh environments.
Handset cover including a robust belt clip.
Heavy duty belt clip with a vibrating option.

The DCU allows the programmed names of each DH2 to be displayed between DH2 users, this functionality is available even when the INDeX DCU is connected to other vendors PBXs.

Index Telephones (new style)

Index CPU & Cassette information

Index Dect Telephones

Index 30

Index General (new style)

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Last revised: January 10, 2023