RU87061U1 - DEVICE FOR IDENTIFICATION OF SUBSCRIBERS TO ATS OF A DECADE-STEP TYPE - Google Patents

Abstract

A subscriber identification system at a ten-day-type automatic telephone exchange, comprising a subscriber line, a preliminary searcher, group searchers, linear searchers, transmitting and receiving devices, characterized in that it further comprises an ATE plus system and a TDB signal detector associated with the first group searchers and with the control module of the first level of the ATE plus system, via the interface.

Description

The invention relates to telecommunications, and in particular to telephone communications, in particular to devices for identifying tones for automatically determining the telephone number (AON) of a caller’s telephone in switched channels of information transmission networks.

Decade-step automated telephone exchanges (DSH ATS) includes an electromechanical finder, consisting of a fixed part - a contact field; the movable part with brushes to create electrical contact with the desired lamellas of the contact field and the drive to move the movable part to the desired position and return it to its original position. Automatic telephone exchanges include urban ATS-47, ATS-54 and rural ATS-100/500, while the finders used in automatic telephone exchanges have a field capacity of 2 to 500 lines and in most cases three wires are switched, of which two (a and b ) are used to transmit conversational currents, control and acoustic signals, and the third wire (s or a ₁ ) is used to test the occupancy and block busy lines. Each subscriber line ends at the PBX with a subscriber set (AK), with every 100 AK being mounted on one cabinet.

Since, in practice, searchers with a field capacity of not more than 500 exits are used, devices for selecting a group are installed, called group searchers (GIs), which select one or more stages of GIs with a group of devices of the next search stage and search for a free device in the selected group, by use a linear finder (LI) serving the desired subscriber group.

DSH ATS has a preliminary seeker (PI) one or more stages of GI and LI stage. At the PI stage, the entire capacity of the station is divided into k subscriber groups, each of which includes n subscriber lines.

The contact fields of the predictors of each subscriber group are paralleled and the inputs of the 1GI device group are included in them. ((B.S. Goldstein Switching Systems, St. Petersburg: BHV-Saint-Petersburg, 2003, p. 47-47)

Because in the DSH PBX, the same devices receive information about the number of the called subscriber and establish a connection, for their successful operation it is required that the pulses and pauses have a fixed duration

Although DSH ATSs are characterized by low quality of sliding contacts, low reliability, high power consumption, they are still widely used in Russia, which makes the problem of their modernization very urgent.

A known method and device based on a modern digital signal processor (DSP), which are designed to send a request signal code AON (500 Hz) via a telephone line to the telephone station (GTS) and remote reception in the tonal range of frequencies of information in a two-frequency tonal alarm system DTMF (Dual-Tone Multifrequency), code “2 of 6”, on the number and category of the caller’s phone using the “interval-free method” (S. Koryakin-Chernyak. Caller ID in telephones. Telephone sets from A to Z, book. 2. St. Petersburg, Science and Technology, 2003 (330 pages); Subscriber device of the UON-51 telephone number caller. Technical description and operating instructions. M., State Scientific-Production Association "STiS" of the Ministry of Internal Affairs of Russia, 2001 (20 pages) .))

The disadvantage of the known AONs, which appeared in the consumer market since 1990 as terminal subscriber equipment, is the relatively low indicators for determining the number of the calling subscriber with deteriorating parameters of the subscriber telephone lines (uneven attenuation and distortion of the frequency response, industrial noise). A multi-frequency broadband signal passing through switched analog communication channels is distorted, since different frequency components are delayed for different times, depending on the parameters of the switched communication channel and the frequency of the signal under study. In addition, their use does not preclude the transfer to the network of a false indication of the calling phone number in order to avoid paying for the service provided.

The closest in technical essence to the claimed technical solution is the technological scheme used at the existing automatic telephone exchanges of the decade-step (ATSC) type for charging long-distance calls to the telephone exchanges. The device used consists of transmitting and receiving devices. (Kalinina VP and other electrician city telephone exchanges. Textbook. M., Communication, 1973, SS.255-258).

The transmitting device is installed on the city or regional telephone exchange, the receiving device is installed on the regional telephone exchange and at the long-distance telephone exchange. The transmitting equipment includes programming devices PU-100 and PU-1000, a general-purpose device for holding the time-delay device, and a group sensor-DG.

The PU-100 is a common device for a hundredth group of subscribers, it is installed for each cabinet and is intended for switching 100 wires of AK of this hundreds when issuing code combinations of numbers, categories, units and tens of telephone number of a subscriber. The PU-1000 includes a group receiver and an electronic pulse pair. The PU-1000 is installed on the thousandth group of subscribers, connected to each PU-100 and is intended to provide information on the numbers of hundreds, thousands, station indices, and the initial sign. OVV is common for one 1GI cabinet, the DG is a station-wide device for the 5000th group of subscribers.

The receiving device consists of an information storage device, a multi-frequency receiver of CP code combinations, a GN signal generator, an exposure relay BB ₁ BB ₂ H electronic pulse pair. When dialing a number, the number is 8, which means access to the long-distance telephone exchange, 1GI sets its brushes on the 8th decade and looks for an exit to the outgoing set of custom-connecting lines IKZSL, which is currently connected with a free intermediate register. The dialed 10-digit number is fixed in the intermediate register PR. After the fixation of 10 digits, the PR is connected to the node requesting and receiving ultrasound information, from which, along the wire a towards the caller, a plus signal is sent along the wires a and b. From the plus incoming on the wire, the CA relay is activated in the 1GI and disconnects the subscriber’s subscriber line from the conversation path. OVV carries out deduction of the relay SA. A frequency signal of 500 Hz UZPI passes through wires a and b through PI, IKZSL, a connecting line, contact SA through PU-100 and PU-1000 to a group receiver. As a result, circuits are created to connect to the PU-1000 of the PU to which the calling subscriber belongs. Information about the operation through the PI, 1GI is fed to the ultrasound scanner, where it is checked and transmitted to the PI.

The disadvantage of this scheme is the ability to make a connection with a false subscriber number indicator.

The problem solved by the author was to increase the reliability of identifying the caller’s number and to eliminate the possibility of unauthorized connections when using a fake call using caller ID, as well as expanding the functions of ten-step-type exchanges such as ATS-47, ATS-54.

The indicated problem was solved by installing the ATC plus systems on all 1GI ATC cabinets together with a TDB signal detector, which is connected to the first ATC group seekers and to the ATE plus first-level control module via an interface.

ATE plus is a three-tier hardware-software system controlled by computers compatible with IBM PC. The general scheme of the system used is shown in figure 1, where the following notation is introduced: 1 - 1GI; 2 - TDB; 3 - block of the 1st level; 4 - control module; 5 - communication lines; 6 - block of the 2nd level; 7 - technical supervisor; 8 - supervisor; 9 - modem; 10 - block of the 3rd level; 11 - server; 12 - computer NT Server; 13 - workstation.

The computer network used for this consists of the following functionally oriented types of computers for each level of the system:

Level 1. The module for monitoring the station - monitors the functioning of the station equipment and captures information about its status. To interface the module with the PBX equipment, multiplexers are used that are installed on the main equipment of the PBX and connected to the corresponding (depending on the type of the PBX) data collection points.

Level 2. The supervisor computer 8 is in communication with the Level 1 modules, receiving Toll-ticket data from them and storing this data on its hard drive. At the facility where several telephone exchanges can be located, one computer is installed - the supervisor. The technical supervisor 7 performs the functions of technical supervision, providing diagnostics and signaling the status of the modules, as well as individual devices of the exchange and is installed on each exchange.

Level 3. At this level there are two types of computers: NT Server 12 and workstations 13. These computers are designed to monitor the state of the entire network and provide access to data on telephone conversations and other connections. NT Server 12, installed on the telephone exchange, collects and stores all the credentials accumulated on Level 2 computers.

The TDB 2 detector is connected to the cabinet 1GI 1, as well as the PBX using a cable through which power is supplied to it. In their work, the detectors are controlled by the extended processor modules of the first level of the ATE plus 4 system. The TDB is connected to the control module of the first level of the ATE plus system through a standard interface, for example, RS-485, for which an RS-485 interface card is additionally installed in the module to be expanded MOXA and related software. This interface allows the sequential inclusion of TDBs in the ATE plus module, serving a specific group of cabinets.

Figure 12 shows a block diagram of a TDB detector board. Fig. 3 is a block diagram of the interaction of the ATE plus System and TDB.

The detector board contains:

- The input unit of the amplifiers, which serves to match the impedances and amplification of analog signals.

- An analog connecting field in the form of a matrix of 20 × 4 or 20 × 8 analog keys, the switching of which is controlled by a microprocessor.

- A block of four or eight-channel decoder, which converts the analog signal into digital form and transmits it to the DSP module for further processing.

- DSP module. The module is based on one or two signal microprocessors. The module performs mathematical analysis of the digital display of the analog signal based on the fast Fourier transform.

- Microprocessor with memory for storing configuration tables and programs for the DSP module

- Dallas identifier, which contains a unique identification code for the detector;

- The input multiplexer is designed for switching the signals of the pulse dialing detector. The output registers are designed to control lock keys.

- Circuits of detectors of pulse dialing DP.

- Electronic key lock circuits have two versions described above;

- RS-485 interface.

- Source of power.

- Connectors for connecting the detector to PBX points, connecting power and for connecting RS-485 interface cables.

The detector has the ability to connect 20 channels-sources of AON signals or other signals (for example: R1.5); blocking, using electronic keys, any of the connected channels, regardless of its status, unambiguous identification through the built-in DALLAS chip.

It is possible to connect several detectors in series via the RS-485 interface to the control module of the first level of the ATE plus system;

The main function of the detector is the detection and control of information at the output of 1GI, the detection of the AON signal, pulse dialing signal, multi-frequency signaling signals and blocking of the outgoing conversation regardless of its state.

The detector is connected to the PBX talk channels using a standard two-row 64-pin DIN 41612 (K2) connector. The detector power is also connected to the same connector. The input channels for detecting acoustic signals (AON, R1.5) are connected to the exchange through a small-capacity isolation capacitor, i.e. have galvanic isolation. In parallel to these channels, pulse-type signal detectors are connected through a 100 kΩ resistor. The electronic interlocking keys that the detector is equipped with, depending on the manufacturing option, close the wires “a” and “b” of the talk channel 1 of the ATC-DSH GI through a 200 Ohm resistor to –60 V or the wire “from” ATSK ISK through a 4 Ohm resistor to + 60V.

To the ATE plus control module, the detector is connected through one of the two (K1, K1A) RS-485 interface connectors. The second RS-485 interface connector is designed for serial connection of other TDB detectors to the ATE plus module. As interface connectors, standard six-contact telephone connectors of the RJ11 type are used.

On the analog interface side, the detector is connected to the PBX at the points indicated in table 1.

Table 1 PBX type PBX Type TDB detector, K2 connector input channels for analysis of ANI signals output channels of blocking PBX connection points ATTSDSh 1GI (20 devices) "B1" ,,, "b20" outgoing “A1” ,,, “a20” “b1” ,,, “b20” outgoing

The system using the TDB detector works on the principle of comparing subscriber number information determined by the ATE plus system and received from the detector upon request of the ATE plus module.

The ATE plus module, upon detection of the first digit set “8” from any subscriber set from the serviced group, determines the subscriber number “A”, converts its number to the full minimum AON code (containing all necessary service codes), fixes the code and gives the command to the corresponding detector TDB for connection to the corresponding 1GI device. From this moment, the detector analyzes all the signals on the “B” wire of this device. When a caller ID signal is detected, the detector receives all the cyclic code information that it transmits to the module upon request, having previously supplemented it with the identification code of the channel from which it was received. The module receives caller ID information in a buffer with a maximum size of 24 code values. After that, the module, in accordance with the channel identification code, compares the previously recorded subscriber caller ID code “A” with the code in the buffer.

If the code combinations do not match, the module transfers information about this event and the devices participating in it to the maintenance computer. Depending on the software, the module either only captures such events, or, at the same time, blocks (resets) the corresponding channel.

The proposed system allows you to organize the following:

- various conditions of conversational state locks:

- blocking a successful conversation in case of incomplete dialing or absence of a subscriber number;

- blocking a successful conversation if the information in the dialing does not match;

- blocking a successful conversation when the pulse dial does not meet the established standards;

- blocking a successful conversation in case of a mismatch of the subscriber number "A" with the information of the caller ID;

- protection against unauthorized access to the subscriber line;

- statistics on all distortions of the information of caller ID, subscriber sets and outgoing devices involved in this.

Claims (1)

A subscriber identification system at a ten-day-type automatic telephone exchange, comprising a subscriber line, a preliminary searcher, group searchers, linear searchers, transmitting and receiving devices, characterized in that it further comprises an ATE plus system and a TDB signal detector associated with the first group searchers and with the control module of the first level of the ATE plus system, via the interface.