Telephony Trainers with Discovery Software

Transcription

1 Teephony Trainers 58 Series Teephony Trainers with Discovery Software Teephony Training System Digita Switching System Digita Teephony Training System Digita Trunk Network System 1

2 Teephony Training Systems P C computer contro TELEPHONY TRAINING SYSTEM RAT Teephone & Interface TDM/PCM Principes P C computer contro DIGITAL SWITCHING SYSTEM Controer Digita Switching Teephone Tray IBM P CPC computer or compatibe contro DIGITAL TELEPHONY TRAINING SYSTEM Controer Digita Switching Digita Switching Teephone Tray Teephone Tray Trunk Networks The addition of board to the System converts it into a Digita Trunk Network System 2

3 Features Covers teephony principes and modern practice Uses commercia teephony components Provides access to a signas Uses Discovery software Automatic practica configuration - no patching Description Teephones and teephony are an essentia part of modern iving and teecommunications is one of the word s fastest growing industries. The demand for technicians and engineers with knowedge of the principes of this area of technoogy wi increase with this growth. This range of Teephony Trainers with Discovery software is a modern, PC-based, computer controed training system that has been designed to introduce and demonstrate the principes of modern teephone systems. The Trainers are a combination of hardware workboards and Discovery software, which together provide a totay integrated deivery system for teaching a wide spectrum of teephony concepts and appications, from the characteristics of individua components to the use of compex systems. 3

4 Compete Systems Each Teephony Workstation consists of: Workstation computer Interface system Rea-time Access Termina (RAT) or Controer One or more Teephony workboards Discovery Software Interface System Discovery Software The Teephony Training System incudes a USB Rea-time Access Termina (RAT) for interface to the PC. The Digita Switching System incudes a Controer unit to provide a the specia power suppies and PC interface circuitry. In combination with the hardware, Discovery Software is suppied with the system. This forms an innovative and motivating deivery system which enabes a wide range of tuition to be carried out. Background theory, board configuration, practica contro, instructions and questions, together with PC-based instrumentation is a integrated into the Discovery environment, suppying a the instruction and measurement requirements for the experiments. The test points used by the PC-based instrumentation in the experiments are dupicated on the workboard, aowing standard Test instruments to be connected if required. Discovery software is a browser-based deivery system enabing instructiona, integrated hardware contro. It aows totay free movement between software screens and has a user-friendy graphica interface. A text is editabe. The computer configuration of the workboards avaiabe with Discovery software eiminates practica set-up time, ensuring that the correct connections are automaticay made. This significanty increases the time avaiabe for actua practica work and the efficiency of aboratory sessions. 4

5 Curricuum In addition to the integra Discovery software, each Workstation is supported by manuas provided on a CD ROM (together with the Discovery software) a Student Workbook and an Instaation Manua. The Student Workbook has been designed to be used aongside the on-screen Discovery software. For each assignment, the Learning Outcomes and Competencies are isted and students demonstrate their achievement of competence by satisfactoriy competing the Workbook. This invoves such activities as suppying missing keywords, competing bock diagrams, making measurements, sketching waveforms, etc. The Workbook has sections for answering the on-screen Discovery questions. In addition, the Workbook is a vauabe revision aid for students, as the key points of the theoretica and background work to assignments are aso incuded. The Instaation Manua detais the hardware and software instaation and operation, the editing faciity, circuit diagrams, etc. It aso contains typica answers to the student activities and questions. 5

6 Teephony Training System Description The system comprises two boards: Teephone and Interface TDM/PCM Principes a RAT (Rea-time Access Termina) and Discovery Software The Teephony Training System is a stand-aone trainer designed to enabe students to study the principes of teephony and gain experience into modern teephony practice. It is a compete package deaing with teephone system theory and practice and combines industry hardware with specia circuits designed to demonstrate the underying principes. The instruction is essentiay non-mathematica and is particuary suited to vocationa and technician eve courses, or for the introductory principes required for further study in teephony systems in undergraduate courses. 6

7 The Teephony Training System contains two workboards and covers a wide range of assignment work. Curricuum Teephone and Interface Workboard Teephone Signaing Switch Hook Keypad Ringing (Aerting) Teephone Speech Receiver Transmitter (Microphone) Teephone hybrid circuit Subscriber s Line Interface Circuit (SLIC) Battery Feed Overvotage protection Ringing (Aerting) Signaing Dua Tone Muti Frequency (DTMF) signaing DTMF Codes Frequency Measurement Tone Duration Speech Immunity SLIC Hybrid Forward oss Return baance oss Testing Test-Out Test-In TDM/PCM Principes Workboard Samping Samping Introduction Aiassing error Interference Mutipexing (TDM) Mutipexing Introduction Time sots and Frames Puse Code Moduation (PCM) Quantisation Quantisation noise Interference Companding Linear Conversion Companding characteristic Companding appication Fitering Aiassing error Fitered conversion Mutichanne PCM 24 and 30 Channe Systems Frame Synchronisation Contro 7

8 Teephone and Interface The Teephone and Interface is an open format board which uses a commercia singe-piece teephone to examine the signaing and speech circuits and the immediate interface at the exchange. The board contains an acoustic couper to enabe a tone signa to be appied to the teephone transmitter. The operation of the teephone handset, the acoustic couper and the circuitry associated with the Subscriber s Line Interface Circuit (SLIC) is investigated, showing the structure of the teephone with speech and signaing circuits and their operation in conjunction with the SLIC. The three signaing circuits of the teephone are examined, as are the three speech circuits. The functions of the first interface circuit are examined. In a commercia system they woud be contained in a Subscriber s Line Interface Circuit (SLIC). Five of the functions of the BORSCHT acronym are covered. The characteristics of dua tone mutifrequency (DTMF) signaing as used for the contro of teephone cas are determined. The use of a high quaity, commercia hybrid in the SLIC enabes usefu measurements to be made. TDM/PCM Principes This board aows the study of the underying principes of time division mutipexing (TDM) and puse code moduation (PCM). It is based on the use of standard teephony devices but aso uses specia circuits to enabe the effects of variabe samping rate, bit rate and fitering to be demonstrated. Puse Ampitude Moduation (PAM) is used to demonstrate the concept of taking short sampes to represent a continuous waveform. Time Division Mutipexing is demonstrated by muti-channe Puse Ampitude Moduation (PAM) which visuay shows the principe of sharing a singe physica ink between different communication channes. Constant vaues and audio sampes are converted into digita form. The effects of quantisation are studied. Linear A/D conversion is compared with compression and expansion using a standard codec. The use of band-pass fiters to avoid aiassing error is demonstrated. The standard 30 channe PCM system is introduced and requirements for synchronisation and contro are discussed. Comparison between 24 and 30 channe systems can be made. 8

9 Digita Switching System Description The Digita Switching System is an easy to use trainer for the investigation of digita teephone switching circuits and their appications. With this system a student may study the principes of digita switching in teephony and aso gain experience into modern teephony practice. The modues use both current standard teephony devices as we as specia circuits designed to deveop an understanding of the methods empoyed. The system aows the performance of a wide range of experiments within the subject area to be investigated. Assignments incude genera introductory materia and each practica is supported by background information and tutoria questions, in the standard Feedback Discovery format. The System comprises a digita switching centre, a controer, four teephones and Discovery software. It is compementary to the Feedback Teephony Training System, Protection is provided on a units to ensure there are no dangerous votages accessibe by the students. 9

10 The assignments cover: Loca signaing Operation Tones and cadences Digita Switch Principes Time switching Time & space switching Digita switch contro Contro of time switch Connection of tones Line scan Switch hook DTMF receivers Ca records Ca state Line identities Ca time Line records Directory numbers Ca accounting Line maps Location maps Condition maps State transitions Inputs Outputs Tasks Ca progress Ca set up Ca suspension Ca reease Manua contro Contro Curricuum Coverage This system progresses from the hardware aspects of digita switching, incuding time and space switching and the contro of a digita switch by a connection memory, to the software aspects of digita teephone switching and contro. Emphasis is paced on the Ca State Transition Diagram, conforming to the CCITT SDL format, for contro of ca progress. The concepts of ca state and state transition are demonstrated in detai. The three stages of ca handing, set-up, supervision and cear down are demonstrated and may be manuay controed by the student. Traffic statistics, testing and programming of the signa tones are investigated. Controer The Controer contains the microprocessor-based circuitry for contro and the specia power suppies required by the teephones and their associated circuits. It interfaces with the PC through a card suppied with the system, with controing code downoaded from the PC on switch-on. This makes for uncompicated upgrading via the Discovery software. Up to three exchanges may be run from one controer. Digita Switching Centre The Digita Switching Centre is an open-board format unit containing four compete teephone ine circuits and a the digita switching and signaing associated with a modern digita teephone system. Two connections to other digita switching centres (trunk interfaces), four teephones and a convenient tray for housing them are aso provided. A system containing two switching centres may be set-up using an additiona, optiona Digita Switching Centre board. Computer Connection The system is suppied with software and hardware to interface to a PC. Power Suppy A power suppies required by the system are provided with the trainer. Testing Test out and oop back Traffic System traffic 10

11 Digita.Teephony.Training.System The additiona curricuum incudes assignments on the foowing topics: Trunk Configuration Trunk paths Numbering Tones and cadences Trunk Switching Outward path Return path Signa Protoco Controer Fags Frame check sequence Zero insertion (bit stuffing) Trunk Signa Units Message signa units Fi-in signa units Description This training system covers a of the work that can be performed with the Digita Switching System and extends it to incude trunk switching and message handing. The System has an additiona Digita Switching Centre and its four associated teephones and incudes eight extra assignments to extend the curricuum to trunk traffic topics. The work that can be carried out with this Trainer progresses from the investigation of oca and interswitching centre numbers and their origination, through trunk switching, highways and timesots, to ca state transition diagrams and ca records for a two switching centre system. CCITT (now ITUT) codes and formats are used. The Trainer is computer-controed and uses Discovery software: an integrated instructiona and hardware contro program which incudes ogic anaysis and dispay of resuts. The instruction is essentiay non-mathematica and is particuary suited to vocationa and technician eve courses, or for the introductory principes required for further study of teephony systems in undergraduate courses. Signaing Information Fied Labe Heading codes Address signas Error Contro Sequence numbers Buffers Trunk State Diagrams Originating switch Diaing Destination switch Trunk Ca Progress Originating switch Diaing Destination switch 11

12 Digita.Trunk Network System The additiona curricuum incudes assignments on the foowing topics: Transit Switching Centre Numbering Transit Switch CSTD Transit Signaing Transit Switching Ca Progress Transit Switch Centre Originating Switch Destination Switch Two Leve Transit Switching Numbering Diaing CSTD Routeing Tabes Description The system comprises: Controer 2 Digita Switching Centre Boards 2 Four Teephone Handset Kits Trunk Networks Board In addition to the curricuum covered by and the Trunks Network Board has three transit switches and extends the work to cover transit switching and signaing. Two Leve Transit Ca Progress Signaing 1st & 2nd Leve Switches Non-associated Signaing Signaing Ca Progress System Testing TCAP Signaing Testing Manua Testing The system can be configured as four oca switching centres, to cover simpe transit switching, two eve transit switching, non-associated signaing and the use of ITU-T type transaction capabiity messages to contro system testing. For ease of use and to accommodate a the modues on the student bench a vertica mounting-rack is avaiabe as an optiona extra. A systems require the use of a standard PC. 12

13 TIMSWIT Timeswitching TIMSWIT is a computer simuation of the process of switching seria digita data transmissions within PCM teephone or ISDN digita networks. It provides interactive demonstrations and exercises for student instruction. Assignments on a aspects of the programme compete a comprehensive package. TIMSWIT A introduces the concepts used in synchronous transmission and the conventions used in the computer simuation. TIMSWIT B shows the operation of a time switch which changes the sequence of data in one data highway, incudes an exercise in controing the switch and aso shows how synchronisation and signaing functions can be provided in the same seria transmission. TIMSWIT C extends the scope to combine time and space switching. Again an exercise in controing this more compex structure is provided. MATSWIT Staged Group Switching MATSWIT is a computer simuation of a three-stage matrix switch which provides economy of switches at the risk of interna bocking. Interactive demonstrations, test routines with storage for the resuts and tutoria materia on a aspects of the programme make up a comprehensive package. MATSWIT A uses a graphica dispay to demonstrate how the switch operates and how bocking may occur even if there are sti free switches and connections. MATSWIT B provides fast operation of the simuation so that statistica profies of the matrix operation with different contro agorithms can be obtained. MATSWIT C simuates continuous use of the matrix at chosen traffic eves to provide aternative comparisons between the agorithms. TELTRAF Teephony Traffic TELTRAF is a computer simuation of a concentration switch in a teephone switching system. Its operation provides an introduction to the basic concepts of traffic theory, giving students practica experience of fuctuating data which has to be described in statistica terms. TELTRAF A modes a concentration switch with 24 inets, 1 to 10 outets. Traffic fow and mean hod time are under the users contro. The connections are seected at random, so that a simuations are unique. The simuation can be operated in singe steps, or aowed to run continuousy, with or without the dispay. Hence users can expore the simuation in their own way, at their own speed. At any time the history graph can be seen which shows the recent sequence of connections against time. Assignments cover basic traffic theory and traffic oss. TELTRAF B covers arger switches, up to 1000 inets and 50 outets, giving a much wider range of possibe simuations. The distribution of occupation of the outets can be dispayed, and stored with the resuts. Assignments are provided on outets (trunk) requirements and cas wait (deay) systems. 13

14 TRAFCALC Traffic Cacuations TRAFCALC is a utiity program for cacuation of the standard distributions used for teephone traffic. Five traffic modes are provided; ERLANG B (cas ost), ERLANG C (cas wait), ENGSET (finite number of sources), BINOMIAL or BERNOULLI (not more sources than servers) and POISSON incuding MOLINA expression for cas waiting. The compete traffic distribution is avaiabe and can be stored with the resuts if required. DATNOD Packet Transmission DATNOD simuates the transmission of data as packets or as a message through the nodes of a wide area computer network. Simuation features are introduced intwo stages. The genera objective of DATNOD is to find the time for transmission of a given set of data, and the effect of many different parameters on the time taken. In DATNOD A ony one node is used, but many other aspects of data transmission can be studied. Assignments are provided to determine the transmission time with different packet sizes and with message switching, or different amounts of data, over different distances and with different transmission rates. In DATNOD B additiona nodes can be introduced, and deay at each node and a sateite ink are possibe. Further assign ments on transmission time are given. Finay, an extended assignment is provided which uses DATNOD to pan packet transmission in a computer network. DATQ Packet Switching Queues DATQ simuates the formation of queues at a node of a packet switching network. The node has up to four inet buffers, from which packets are transferred to a queue, where they wait to be transmitted from an Outet Buffer. The features of the mode are graduay introduced in three stages. In DATQ A the M/M/1 queue is introduced. Assignments are provided on statistica fuctuations of the queue parameters, on the variation of queue ength and time deay with usage of the node, and on the oss of packets if the queue is not sufficient. In DATQ B other queue discipines can be observed. These incude the M/G/1 and M/D/1 types. Queue behaviour with fewer inets can aso be seen. Further assignments are possibe on queue ength, time deay and packet oss in a wider range of situations. In DATQ C a aspects of the node are under the contro of the user, incuding transmission rates for the inets and outets, and a queue type which can be defined by the user, aowing a wide range of nodes to be modeed. DATQ is aso suitabe for students concerned with queueing theory in other discipines. 14

15 Tender Specifications Teephony Training System A sef-contained, open-board based, Teephony trainer using software contro and computer-assisted instruction. The system shoud contain a 100Msampe/s Rapid Access Termina with USB interface (to connect to a PC with a Windows operating system); Teephone and Interface workboard; TDM/PCM Principes workboard and accompanying software. The system shoud operate with computer aided aboratory software which provides on-screen instruction, contro and instrumentation for tweve computer-based assignments are provided with the system. Digita Switching System A sef-contained, open-board based, Digita Switching Teephony trainer using software contro and computer-assisted instruction. The system shoud contain a Controer with power outputs and microprocessor-based circuitry for contro; USB interface (to connect to a PC with a Windows operating system); a Digita Switching Centre workboard; four teephones with teephone tray and accompanying software. The system shoud operate with computer aided aboratory software which provides on-screen instruction, contro and instrumentation for tweve computerbased assignments are to be provided with the system. Digita Teephony Training System A sef-contained, open-board based, Digita Teephony trainer using software contro and computer-assisted instruction. The system shoud contain a Controer with power outputs and microprocessor-based circuitry for contro; USB interface (to connect to a PC with a Windows operating system); a Digita Switching Centre workboard; four teephones with teephone tray and accompanying software. The system shoud operate with computer aided aboratory software which provides on-screen instruction, contro and instrumentation for twenty-four computerbased assignments. Digita Trunk Network System A sef-contained, open-board based, Digita Trunk Networks trainer using software contro and computer-assisted instruction. The system shoud contain a Controer with power outputs and microprocessor-based circuitry for contro; USB interface (to connect to a PC with a Windows operating system); two Digita Switching Centre workboards; eight teephones on teephone trays and accompanying software. The system shoud operate with computer aided aboratory software which provides onscreen instruction, contro and instrumentation for thirty computer-based assignments. 15

16 Teephony Trainer Product Numbers Listed beow are the product numbers of the constituent parts of the two Teephony Trainer Workstations. Each of the workstations may be ordered as a compete system, using the composite order numbers given at the start of the reevant section. However, shoud you wish to cover ony part of the described curricuum you may not need a of the modues in the workstation. In such cases you may order just the modues that you do require. Pease contact either your oca agent, or Feedback, if you require more information. Teephony Training System composite equipment: Rapid Access Termina (RAT) Teephone and Interface TDM/PCM Principes Teephony Trainer Discovery Software Digita Teephony Training System composite equipment: Controer Digita Switching Centre x Teephone Tray x Digita Switching System Discovery Software Digita Switching System composite equipment: Controer Digita Switching Centre Teephone Tray Digita Switching System Discovery Software Digita Trunk Network System composite equipment: Controer Digita Switching Centre x Teephone Tray x Trunk Network Board Digita Switching System Discovery Software Ordering Information To order any of the Teephony Systems simpy quote the tite and number of the workstation as given at the start of each section. For further information on Feedback equipment pease contact: Park Rd, Crowborough, East Sussex, TN6 2QR, Engand. Te: +44 (0) Fax: +44 (0) E-mai: feedback@fdbk.co.uk Website: Feedback reserves the right to change these specifications without notice. Registered in Engand number A subsidiary of Feedback pc. 16 Teephony Trainers 58 series - 4 Printed in Engand by FI Ltd, Crowborough 0706