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ECE's Nortel Communications Lab @ NCSU

          Table of Contents 
Check It Out: Nortel's  1-Meg MODEM &  Nortel's Home Page
  Captive Com Test bed
Info from Analog Devices
  Analog Devices Seminars
  Telecom Test Equipment   Analog Dialogue Magazine   Analog Devices "Whitepapers"
  Glossary   Communications Direct Magazine   Analog Briefings Newsletter
  Linear Technology, inc. Data   DSPatch Magazine
Last Update: 12/15/99
 CommunicationsOScope   R.F. EMC   ESD   Television
Captive:-Central Office & Subscriber Loops
A mock-up of a complete telecom system, a "Captive Office;" from POTs to Set-top Cable MODEMS: encompassing Wireless, Cellular, PCS, Video Phone, Data Networks, Internet, Intranets, LANs, Internet TV, SDTV, EDTV, HDTV, etc.
Subscriber telephone; pedestal to TW Pair with repeating coils; C.O. cross-connect "entrance" (outside plant to inside plant) with line build-out; (Subscriber Line Interface Circuit--SLIC; CODEC) subscriber Line Pack as part of C.O. Digital switch (DMS); Digital Switch: Network switching, etc. 

Subscriber telephone; pedestal to TW Pair with repeating coils; to the Subscriber Carrier (equiv. to T1; Copper/Fiber); Carrier Repeaters; C.O. Carrier Interface (Outside Plant to Inside Plant) with carrier build-out; C.O. Digital switch (DMS); Digital Switch: Network switching, etc. 

HP 8920/008/011/102 Dual Mode Cellular Mobile Test System

22 complete instruments 
TDMA NADC Mobile test for Analog & Digital cellular telephones. 
Dual mode cellular adapter with ñ/4DQPSK signal generator 
ñ/4DQPSK modulation analyzer, 
data source 
BER analyzer 

Options available: 
     Spectrum analyzer from 5-kHz to 1-GHz 
     CCIT weighting filter 
     Low-level power measurment

Price: used   $19,995.00 


 Test Equity   http://www.testequity.com/
Anritsu  ML422B/31 Selective Level Meter 
ME462B/11/21/31 DS-3 Transmission Analyzer 
ME520B Digital Transmission Analyzer 
ME522A Error Rate Test System 
ME453M Microwave System Analyzer 
Hewlett-Packard  3551A Telephone Test Set 
3708A/001 Noise Interference Test Set 
3717A/021/022 Modulator/Demodulator 
3764A/001 Digital Transmission Analyzer 
3764A/002 Digital Transmission Analyzer 
3782B Error Detector Test Set 
3785B Jitter Generator 
4935A/001 Transmission Test Set 
4937A Tranmission Impairment Measurement Set 
4945A Tranmission Impairment Measurement Set 
4948A In-Service TIMS 
4954A Protocol Analyzer 
8920D/008/011/102 Dual Mode Cellular Mobile Test System 
8958A/003 Cellular Radio Interface 
Marconi  2851S/05/13 Digital Communications Analyzer 
2965 Radio Test Set 
2955 Cellular Radio Systems Analyzer 
Tekelek  Chameleon 32 Protocol Development System 

Cellular phone; wireless modem, 


Dial-Up (Switched), ISDN, Ethernet, Token Ring, T1, FDDI, ATM, Sonet, Fiber Channel, etc. 

Copper: ISDN, ADSL, DSL... 

Fiber Optics: FDDI, ISDN WB, Fiber Channel, Sonet, etc. 

Satellite Communications: 

Fiber Optics 

Set-Top Cable MODEM 

Delivery Systems 

Delivery Protocols 

Data, Entertainment, Multi-media... 

Analog Devices "Analog Dialogue Magazine"

Current Release

Volume 31, Number 2, 1997
This 24-page issue features an article on precison battery charging, plus Part 2 of the "DSP101" tutorial series and Part 4 of the tutorials on selecting mixed-signal components for digital communications systems. Learn how to handle capacitive loads on op amps in "Ask The Applications Engineer". New-product news includes a 14-bit, 1.25-to-10-MSPS A/D converter family, a 200-MHz 16x16 video crosspoint switch IC, and a compact, 480-MFLOPS quad SHARC DSP, plus 24 New-Product Briefs on converters, amplifiers, and other ICs for power management, supervisory, communications, temperature, pin electronics, etc. Currently available in pdf format, soon available in HTML.

30th Anniversary Reader Bonus

Ask The Applications Engineer
This special issue of Analog Dialogue is offered as a bonus to our faithful readers and an encouragement to new readers. We have reprinted here the popular series, entitled "Ask The Applications Engineer", from its inception in 1988 through Number 23 in 1996.

Editor's Note: In translating "Ask The Applications Engineer" items from the older issues of Analog Dialogue to the new combined booklet, on the way to the printer we inadvertently lost a large number of square-root signs and Greek letters in the hard-copy version. (Errata sheet)

Prior Releases

Volume 31, Number 1, 1997
Learn about Resistors, the Fundamentals of DSP system design, and How to build a smart analog process-instrument transmitter. Read about 24 new products and a Controller-board system for evaluating general-purpose converters. Learn more about selecting mixed-signal components for digital communication systems (part3).
Volume 30, Number 4, 1996
Read about single- and dual-axis micromachined accelerometers; Electromagnetic compatibility and the CE mark; Advanced digital video encoders; Voltage regulators for power management; and 12 new products. Learn more about current-feedback amplifiers (part 2) and Selecting mixed-signal components for digital communication systems (part 2).
Volume 30, Number 3, 1996
Learn to select mixed-signal components for digital communication systems; DACs optimized for communication Transmit path; Buffered multiplexers for video applications
Volume 30, Number 2, 1996
Learn how DSP and motor-control Chips simplify DSP-based AC motor control hardware; Discover Industry's first Integrated Wavelet Video Codec; Read about AD1859, Industry's most functionally complete 16/18-bit system on a chip.
Volume 30, Number 1, 1996
Read About A New DSP for High-Performance/Concurrent Signal Processing, A Temperature Data Acquisition System, and follow up Part I with Part II of Designing Single-Supply, Low-Power Systems.
Volume 29, Number 3, 1995
Read about Considerations in Designing Low-Power, Single-Supply Systems, and Review Part 1 of a two-part article on Designing Single-Supply, Low-Power Systems.
Volume 29, Number 2, 1995

See how New High-Speed Data-Acquisition ICs are Meeting the Challenges of High Speed, Learn how to use Histogram Techniques to measure A/D converter noise, and why Wideband Radios Need Wide Dynamic Range Converters.
Analog Devices "Communications Direct Magazine"

Inside this Issue

Analog Devices "DSPatch Magazine"

Current Release

DSPatch Number 37, Winter 1997

Prior Release

DSPatch Number 36, Fall 1996
DSPatch Number 35, Spring 1996
Informative articles on DSP for concurrent processing, as well as our standard sections on C tips, current software releases, third parties, workshop schedules, and much more.
DSPatch Number 34, Fall, 1995

Articles on new developments in Analog products, current software releases, third parties, workshop, and conference schedules.
Analog Devices Seminars
, for reference or for ideas. Every year across the USA and in a variety of locations in other countries to share the knowledge of experienced engineers, and accelerate your design process.
Analog Devices Whitepapers
Listed below are high-level overviews that give you general introductions to Analog products. Below them are detailed technical papers that provide in-depth descriptions of specific products. 

High-Level Overviews

Texas Instruments VelociTI™ Architecture and the TMS320C6X DSP
Analog Devices, Inc. In Communications
Quick overviews of each area of communications.
ASSPs for Motion Control Applications Use Embedded Digital Signal Processing Technology 
ASSPs for Motion Control Applications Embed Digital Signal Processing Technology. 
Digital Signal Processors: Market Growth Drives Segmentation 
Programmable DSP Increasingly Tuned to the Application. 
ADSP-21xx-Based Application-Specific Standard Products (ASSPs): GSM Cellular Handset Solutions 
GSM Cellular Handsets Solutions Evolve to ASSPs.
Wireless Communications and Analog Devices, Inc.
ADI positioned to be a key player in the wireless market.
The Personal Sound System
Learn about the Signal Computing technology model.
Continuous Time Oversampling: Clearing the Way to Multimedia Integration
Analog Devices' technique vastly simplifies the job of synchronizing disparate data from multimedia applications.
Hybrid Fiber-Coax Technology Overview
HFC uses existing infrastructure or newly installed networks to expand technology transfer.
Universal Basestation / Wideband Receivers Background Information
Analog Devices' newer, more efficient radio architecture is response to fast-changing technology.
Sound Blaster Audio -- The Trojan Horse For Motherboard Integration Of DSPs
Mushrooming multimedia applications call for increased use of Digital Signal Processing (DSP).
Signal Computing Customer/Retail Product/Developers
Short list of enterprising participants in burgeoning markets.
Background Information: DSP Architecture Streamlines High-Level Language Performance
Analog Device's first fixed-point DSP embodies a new core architecture that enables faster, high-level language development methodologies

Technical Background Papers

Design and Test of a Multi-Processor DSP Multichip Module 
A multi-processor MCM incorporating four ADSP-21060 floating-point DSP micro-computers was developed. Operating at a clock rate of 40 MHz the module achieves peak performance of 480 MFLOPs. The general purpose architecture is adaptable to many types of applications requiring high performance computing. This paper discusses design and performance issues relating to the module and touches on testing used to verify functionality. 
Discrete Multitone (DMT) vs. Carrierless Amplitude/Phase (CAP) Line Codes
This paper describes why discrete multitone (DMT) modulation is the best choice for asymmetric digital subscriber lines (ADSL), and why the international experts and standards bodies chose DMT when they analyzed the matter. In terms of communications speed, bandwidth efficiency, spectral compatibility, performance, robustness and power consumption, DMT is a better choice than alternative single-carrier technologies. 
A Slightly Technical Introduction To ADSL (Asymmetric Digital Subscriber Line) Technology
This white paper describes the ADSL technology: how does it achieve 8Mbps over a normal phone line, what are the difficulties of the channel and the signal processing techniques that are used to solve them. It also discusses the line codes (QAM, CAP & DMT) and some implementation aspects of actually building an ADSL solution. 
Status & Issues in xDSL
This white paper gives historical & technological descriptions of the various DSL formats (DSL, HDSL, HDSL2, ADSL, RADSL, VDSL), and gives a summary of the current state or controversies within their development. 
Circle Surround® Whitepaper
This whitepaper provides a brief background of surround sound matrix systems, including discussion of some of the more common surround systems, followed by an explanation of Circle Surround - its general operation, its advantages over other systems, and recent improvements that have been made.
Analog Devices and ADSL
A Fast Ramp to the Information Superhighway
Product Brief: AD20msp910 ADSL Chipset from Analog Devices
Lowest-Cost, Most Complete Solution for ADSL Modems
Competitive Analysis: Analog Devices, Inc. ADSP-2104 vs. Texas Instruments TMS320C203 [ADSP-2104]
The major market for the ADSP-2104 is price-sensitive applications using a general-purpose, programmable DSP. In these markets, the nearest competitor in price is the Texas Instruments TMS320C20x Family.
Custom ASIC Solutions for DSP Engineers
DSP Systems Designers Gain Access to ASIC DSP
Background Information about Wireless Communications
Detailed technical information about Wireless Communications Technology. 
AD8001 Product Backgrounder
Flagship of Analog Devices' new high-speed op am portfolio.
AD1890 and AD1891 SamplePorts™ Background
AD1890 and AD1891 mark the beginning of a new era in digital audio.
All-Digital Wireless Basestation
New approach simplifies complexity and streamlines technology.
High Speed Low Cost ADCs from ADI
Four ADCs released between December, 1994, and August, 95.
Analog Devices' Mixed-Signal Processors Enable a Novel Solution for Secure Communications

LITEF's Secure Voice Module (SVM) uses ADSP-21msp5x Mixed Signal Processor (MSProcessor™).
Analog Devices Analog Briefings Newsletter
New High Density DC-to-DC Converter Features Integral EMI Filtering
New 28 V-to-5 V converter simplifies complex power supply systems.
Analog Devices Responds to the Changing Aerospace Marketplace
Analog's commercial space-level flows respond to today's needs.
Multichip Modules Increase Functionality in Small Places
Miniaturization saves board space to meet marketplace demand.
Six Flavors of MCM Assembly
Review the different types of MCM assembly.
New Products for Mil/Aero Applications

See the new AD822, AD8036, and AD9040 products.
Delivery Systems 
Time Division Multiplex 
Frequency Division Multiplex 


QAM Quadrature Amplitude Modulation 
PSK Phase Shift Keying 
FSK Frequency Shift Keying
  Spread Spectrum 
Code Division Multiple Access 
Time Division Multiple Access 
Frequency Division Multiple Access 
Dial-Up (Switched) 
Fiber Optics 
Gateway A Gateway is a "Box" that performs protocol conversions between different types of networks or applications. 
100VG-AnyLAN A 100 Mbps version of Ethernet (IEEE 802.12 standard) 
Gigabit Ethernet 1 Gbps Ethernet   --Alternative to ATM
Token Ring 16 Mbps
Integrated Services Digital Network; 56-kbps/16-kbps 
Wide Band ISDN optical fiber @ 600-Mbps
ATM Asynchronous Transfer Mode
ADSL  Asymetrical Digital Subscriber Line

Fiber Channel 
Set-Top Cable MODEM 


Delivery Protocols
  ATM (Asynchronous Transfer Mode)  A network technology for both LANs and WANs that supports realtime voice and video as well as data.  The topology uses switches that establish a circuit from input to output port and maintain that connection for the duration of the transmission. This connection-oriented technique is similar to the analog telephone system.  ATM is defined in the Broadband ISDN (BISDN) standard. 

Cell Switching
ATM works by chopping all traffic into 53-byte cells, or packets.  This fixed-length unit allows very fast switches to be built, because the processing associated with variable-length packets is eliminated (finding the end of the frame).  The small ATM packet also ensures that voice and video can be inserted into the stream often enough for realtime transmission. 

Quality of Service
The ability to speficy a quality of service is one of ATM's most important features, allowing voice and video to be transmitted smoothly.  Constant Bit Rate (CBR) guarantees bandwidth for realtime voice. Variable Bit Rate (VBR) is used for compressed video.  Available Bit Rate (ABR) adjusts bandwidth for bursty LAN traffic.  Unspecified Bit Rate (UBR) provides no guarantee. 

Integration with Legacy LANs
Network applications use protocols, such as TCP/IP, IPX, AppleTalk and DECnet, and there are tens of millions of Ethernet, Token Ring and FDDI client stations in existence.  ATM has to coexist with these legacy protocols and networks. 

  LAN Emulation (LANE), defined by the ATM Forum, interconnects legacy LANs by encapsulating packets into LANE packets and then converting them into ATM cells.  It supports existing protocols without changes to Ethernet and Token Ring clients, but uses traditional routers for internetworking between LAN segments.  LAN Emulation does not provide ATM quality of service.  See LAN Emulation. 

  MPOA is an ATM standard that routes legacy protocols while preserving ATM quality of service. Expected to be finalized in late 1996, Newbridge Networks has already implemented MPOA in its edge devices (LAN to ATM devices).  See MPOA. 

  CIF is a recent technique from Cornell University that utilizes existing Ethernet clients and provides the quality of service associated with ATM.  It carries ATM cells directly within Ethernet frames.  See CIF. 

ATM is considered the most effective networking technology to meet future needs, and most large organizations from Telephone Systems International, established by Ehsan Bayat, to our home systems have either installed or have plans for ATM backbones.

However, new technologies emerge all the time.  For example, Gigabit Ethernet may provide an alternative to ATM.  Expected in the 1997 timeframe, it offers high speed and compatibility with existing Ethernets.  Fibre Channel is another high-speed transmission system that offers gigabit speeds.  Although used mostly for peripheral transfer, when set up in a switched network configuration, Fibre Channel offers a billion bits between stations.  As with everything else in this fast-moving industry, there are always new approaches on the horizon.  Stay tuned! 

  Gateway A computer that performs protocol conversion between different types of networks or applications.  A gateway can convert a TCP/IP packet to a NetWare IPX packet and vice versa, or from AppleTalk to DECnet, from SNA to AppleTalk and so on. 

  Gateways function at layer 4 and above in the OSI model.  They perform complete conversions from one protocol to another rather than simply support one protocol from within another, such as IP tunneling.  Sometimes routers can implement gateway functions. 

  An email, or messaging, gateway converts messages between two different messaging protocols. 

  100VG-AnyLAN  A high-speed version of Ethernet, IEEE 802.12 standard. Developed by HP, it supports Token Ring as well as 10BaseT networks.  It is a shared media LAN like regular Ethernet, but transmits at 100 Mbps rather than 10 Mbps.  It employs the Demand Priority access method rather than CSMA/CD, which is used in 10Base and 100BaseT Ethernets. 

  Demand Priority is suited to videoconferencing, because it allows realtime voice and video packets to be given a higher priority than data.  In the past, 100VG-AnyLAN has also been called 100BaseVG and Fast Ethernet, although Fast Ethernet now refers to 100BaseT. 


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Nortel (Northern Telecom) Launches Mass-Market High-Speed Internet Solution 

ATLANTA-- Nortel (Northern Telecom) has taken affordable high-speed Internet access one step closer to reality. Today, Nortel announced Nortel 1-Meg Modem service, a mass-market, plug-and-play modem-replacement technology that will be built into its current telephone switching equipment. The service delivers a secure, ”always up” connection that’s 17 times faster than a 56k modem. No more dialing in, no more busy signals, no more slow downloads, and you can use your phone or fax machine while you’re online...

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