GSMCDMA transceivers

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GSM-CDMA transceivers
Special Telecom Solutions

• The most common faults
• and the Dielro solution

Addressed to all Chairmen and Managing
Directors Changing brand is EXPENSIVE... Not
doing it, could be even more expensive
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INTRODUCTION
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• A large part of intruder detection security
  systems use GSM-CDMA transceivers. This is why
  there are so many devices on the market, of many
  different brands.
• Dielro has carried out research based on
  technical, functional and legal analysis of a
  great many systems, obtaining a series of data
  that have made it possible to prepare this
  document.
• We hope it is of great help to you.
• Dielro
• Special Telecom Solutions

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SENSITIVE TO ELECTROMAGNETIC INTERFERENCE
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• The use of GSM-CDMA systems involves the
  transmission of RF signals. This makes it
  necessary to maintain isolation between the
  transmission stage and the remaining circuitry.
  Many systems on the market have the problem of
  not being sufficiently shielded, even failing to
  comply, in many cases, with EMC standards EN
  55022 and EN 55024. We have reached this
  conclusion thanks to the opportunity we had to
  test many systems in our laboratories.
• The Dielro solution
• As an example Dielro has been able to develop a
  system sealed in a plastic box, with a built in
  antenna and, without using any type of interior
  shielding, to obtain the correct immunity
  measurement.
• This has been possible thanks to the use, for the
  first time, of a plastic material that includes
  metal particles injected into the structure and
  which are aligned inside, so that they create a
  perfect shield. We thereby obtain a legal and far
  more economical product.

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BADLY ADAPTED INTERIOR AND EXTERIOR LINES
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• On systems with interior telephone lines, the
  bi-directional transmission of audio signals
  through a telephone pair requires the use of a
  hybrid coil, in order to prevent the headphone
  signal being re-sent as a microphone signal. In
  many cases, the use of a GSM-CDMA link does not
  ensure that the hybrid, or internal split
  circuit, employed will have the rejection set
  high enough to stop the signal sent to the
  analogue telephone earpiece from being
  transmitted back to the telephone channel.
• The Dielro solution
• The level of audio quality on Dielro systems is
  extraordinary, thanks to the advanced technology
  used. Whenever someone tries it out, they are
  pleasantly surprised.

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SENSITIVE TO BLOCKING (1)
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• In many cases, with just a call made to the
  GSM-CDMA communications equipment at the
  installation, it is possible to keep the
  communication channel occupied. In this situation
  the security installation located in the building
  will not be able to transmit any events to the
  alarm receiving centre. This is well known by
  many professional thieves.
• The Dielro solution
• Dielro systems only accept previously authorised
  incoming calls, while all the rest are rejected.
  This allows to maintain the outbound channel free
  at all times.

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SENSITIVE TO BLOCKING (2)
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• Many systems landline (PSTN) supervision circuit
  has a very slow speed of response. It is possible
  in this case to sabotage the system by using a
  simple battery. The line is cut, and the battery
  is quickly connected at the subscribers local
  line part. This way the building installation
  line will believe that the telephone line is
  still active, because it has not detected any
  cut, when the reality is that the PSTN line is
  cut and the thief knows this. The alarm call
  centre will never receive any notification.
• The Dielro solution
• Dielro systems detect voltage and dialling tone
  in the PSTN network and have very fast circuits
  that are able to detect any line cut. And in case
  this occurs, the alarm receiving centre is
  immediately informed by the GMS-CDMA network
  through SMS, GSM, IP (GPRS), etc., depending on
  what is available.

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SENSITIVE TO BLOCKING (3)
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• When receiving a call (GSM-CDMA or PSTN), many
  GSM-CDMA transceivers at the security
  installation interpret this as a programming call
  and do not reject it. The communications channel
  is then occupied.
• In case an event is generated at the same time at
  the buildings alarm control panel, because a
  thief broke in, the panel, by occupying the
  communications channel, sends signals to the
  alarm receiving centre. But an expert thief may
  from the same mobile telephone simulate the
  signals sent by the receiving centre.
• The Dielro solution
• Dielro systems identify any types of incoming
  calls and only numbers authorised for programming
  may gain access to the system. All the rest are
  rejected.

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NEED FOR ACCESSORIES
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• Many GSM-CDMA systems require the use of extra
  management devices such as computers, memory
  recorders, special equipment and other devices to
  make changes to the programming. Which makes
  installation more difficult, losing time
  unnecessarily.
• The Dielro solution
• Dielro systems can be programmed in very diverse
  ways, the most common ones being with SMS
  message, through IP connection (GPRS), PSTN call,
  etc. It is always possible to choose those that
  require less time to be performed, whilst also
  preventing unnecessary risks.

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NEED FOR A CELLULAR TELEPHONE TO ACTIVATE THE
SIM
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• Most GSM-CDMA equipment do not allow the PIN to
  be entered directly from the private line (PTN),
  a mobile phone being necessary in order to do
  this. Furthermore, some manufacturers recommend
  the use of a standard PIN recorded on the board,
  which is indicated in the freely available
  technical documents on the Internet.
• When a system has an private line (PTN), this
  should be sufficient to activate the SIM.
• The Dielro solution
• If the system has an private line (PTN) it will
  be unnecessary to activate the SIM card with a
  cell-phone, and you will just have to follow the
  procedure by using a DTMF telephone, the one
  available at home for instance, but without
  having to handle the card.

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LOSS OF DATA DUE TO OVERFLOW
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• Many GSM-CDMA transceivers have a LIFO battery to
  record rapid sequential events, but this memory
  does in most cases have very little capacity,
  causing the loss of events to be sent.
• The Dielro solution
• All GSM-CDMA systems developed by our brand have
  sufficient storage capacity (32 events).
• Consider moreover the communication reliability,
  which means there is very little risk of massive
  storage, as is the case with other systems.

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LACK OF BACKUP SYSTEM
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• Many devices on the market offer no record of
  occurring events, nor the possibility of storing
  logs in a non-volatile system.
• The Dielro solution
• Our GSM-CDMA equipment have a backup system which
  allows them to store a whole range of data that
  are very important for the maintenance company.

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DEFICIENT TECHNICAL INFORMATION
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• Information about installation, programming,
  operating and maintenance is usually confusing
  and incomplete. The technicians have their hands
  tied.
• The Dielro solution
• As well as full technical documentation, all
  Dielro products have at their disposal the
  possibility of remote assistance from our
  technical service Call Center, in English and
  Spanish. Dielro equipment may be checked and
  programmed remotely. And for any type of special
  consultations, there is an international applied
  engineering department.

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INEXISTENT LEGISLATIVE DOCUMENTS
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• Many devices on the market often lack any of the
  legislative documents required in directive
  99/5/EC and the corresponding harmonised
  standards. They do not have the compulsory
  Declaration of Conformity or it is not correct,
  which does in any case mean that it is false (an
  offence in most European countries).
• They also fail to meet required standards in
  other countries where they are marketed, as in
  the USA, FCC part 15, etc.
• What problem would you have if, in case of a
  serious occurrence, the system is shown to be
  illegal?
• The Dielro solution
• All systems have their Declaration of Conformity,
  as well as the corresponding Technical File,
  required in all New Approach European directives,
  where all technical information relating to
  components, tests, manuals, diagrams, etc. is
  recorded.

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NON-TRANSPARENT TRANSMISSION
Special Telecom Solutions

• Certain devices, when they detect a DTMF tone on
  the private line to be sent via GSM, filter and
  process it, then generate another internal DTMF
  tone that is the same, BUT WITH A FIXED LEVEL AND
  DURATION, GENERALLY DIFFERENT FROM THE ORIGINAL
  ONE. This change of characteristics causes many
  problems, especially in devices that create
  proprietary protocols or security protocols with
  alarm receiving centres.
• This leads to habitual loss of information.
• The Dielro solution
• Dielro GSM-CDMA systems are totally transparent.
  This means that the signal obtained inside the
  installation is sent to the cellular network in
  its original form.

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FILTERING (A, B, C and D) DTMF
Special Telecom Solutions

• The DTMF protocol includes, as well as the 12
  DTMF keys associated with any telephone, another
  4 which are used in special cases (A, B, C and
  D). Some GSM-CDMA links filter the transmission
  of these tones. This makes it impossible to
  establish communication with the systems that use
  these characters (e.g. Contact ID).
• The Dielro solution
• Dielro systems do not filter any of the DTMF
  signals.

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LINE DISTORTION OF DTMF TONES
Special Telecom Solutions

• Many systems, when they attempt to transmit
  signals with DTMF tones, as well as other
  harmonic signals such as those used with modems
  (V.21, V.23 and higher) and fax signals (Group
  III), the GSM link VOCODER may not be able to
  encode them.
• The problem appears when the GSM-CDMA device has
  the HF (Half Rate) or other modes enabled and not
  just the FR (Full Rate) mode. The reason for this
  is that the mobile network operator may propose
  a communication speed to the GSM-CDMA link that
  is lower than standard, and during the
  negotiations prior to making the call it may
  require the use of a low-velocity VOCODER,
  resulting in a loss of quality.
• If the GSM-CDMA system accepts, tone
  transmission will not be possible or many
  communication errors will appear.
• The Dielro solution
• Dielro systems only use the FR mode.

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LACK OF ALTERNATIVE ROUTES
Special Telecom Solutions

• When a robbery occurs, in the event of a failure
  in the main communications network, some systems
  are not equipped with an alternative network to
  allow them to transmit the event that has been
  detected and thus avoid further occurrences.
• The Dielro solution
• Dielro GSM-CDMA systems, even the basic ones, can
  use several communication networks and
  possibilities. For example PSTN, GSM, GPRS, SMS,
  Modem.
• They can also be provided with GPRS polling,
  which most other devices do not have.

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BADLY DIMENSIONED POWER SUPPLY CIRCUITS
Special Telecom Solutions

• Power supply circuits are usually extremely
  sensitive and are normally dimensioned to satisfy
  the best possible coverage conditions. With less
  cellular network coverage, there is greater power
  consumption. This involves operating at a forced
  rate, at the limit, when the signal level is low.
  
• The Dielro solution
• Dielro pays special attention to power
  processing. Dangerous consumption levels, caused
  by a badly dimensioned power supply circuit, are
  never reached. And in case batteries are used,
  they are permanently checked in real time in
  order to determine their capacity level.
  Something that, for many manufacturers, simply
  involves measuring the voltage.

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LACK OF PROTECTION
Special Telecom Solutions

• Generally, many of the designs for these types of
  systems do not consider protection against rapid
  drops in incoming power, filters on interior and
  exterior telephone lines or protection against
  surges or electrical disturbance. This leads to
  poor quality of the product.
• The Dielro solution
• All Dielro systems are equipped with the
  necessary protection to avoid damage that would
  affect the proper working of the installation.

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LIMITED REMOTE ACCESS
Special Telecom Solutions

• Most GSM-CDMA systems on the market allow access
  to the subscribers security control panel,
  calling exclusively through the PSTN network.
• If you do not have a landline available, then you
  have a problem.
• The Dielro solution
• All Dielro systems can be provided with a ring
  generating circuit, so that by calling through
  the GSM-DCMA network it is possible to gain
  access to the subscribers control panels
  circuits, using the established protection, the
  same as if you call via the PSTN line.

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NO MORE POSSIBILITIES
Special Telecom Solutions

• Most systems on the market
• If the landline network is cut, they tell you
  they will contact you via the GSM-CDMA.
• If the mobile network is cut, they say they will
  contact you via the PSTN.
• And when both systems are cut ?
• The thief is completely free to steal, without
  the Alarm Receiving Centre being able to find
  out.
• The Dielro solution
• When both systems are cut off, there is always
  NetKeeper, a network monitor that works via 3
  networks simultaneously and, in case all three
  are cut, the Receiving Centre will immediately
  know. When you need greater security, Dielro is
  always the solution.

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And now that you know what Dielro is, will your
company continue losing money?
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• Now you know what Dielro can do for you. You only
  need to try one of our systems and your doubts
  will be quickly dispelled.
• The price?
• Please ask for quotation.
• It will be the best offer you have ever seen.
• Furthermore, remember that Dielro products range
  from the simplest system to the most
  sophisticated one, for those customers who desire
  maximum security.
• Dielro
• Special Telecom Solutions
• www.dielro.com