DIGITAL COMMUNICATION

Transcription

1 DIGITAL COMMUNICATION TRAINING LAB Digital communication has emerged to augment or replace the conventional analog systems, which had been used widely a few decades back. Digital communication has demonstrated more effective techniques to conserve the radio spectrum by providing new, more efficient modulation and coding methods and a wide variety of Analog-to Digital-Conversion techniques. These techniques are made possible by the parallel development of solid state technology. Digital Communication Training Lab Trainers give practical ways to understand and implement Digital Communication Techniques. Digital Communication Training Lab is a series of eleven kits, which acts as an aid to practically see, experiment and learn the digital techniques applied to communication. These kits, when used with a low frequency Spectrum Analyzer, can show the waveform in Frequency Domain and Eye-Pattern to understand aliasing, signal drops etc. This system is very useful for Engineering Colleges, Polytechnics, IIT s and Defence and Communication Staff Training Centers to impart practical aspects of Digital Communication Techniques. These trainer kits are provided with extensive Test points allowing students to investigate the various aspects of system operation. Each kit is equipped with correlated courseware to guide students through the application and demonstration of communication techniques and concepts. In addition user manual guides students through each kit. An interactive user-friendly e-manual software is provided optionally with this training lab on CD. DCL - 01 ANALOG SIGNAL SAMPLING AND RECONSTRUCTION KIT This kit facilitates students to understand the principles of Analog signal sampling and its reconstruction. Onboard signals are provided to see effect of different sampling frequencies on different analog signals. Concept of sampling theorem is very well understood using this trainer kit. Analog signal sampling : Sample & Hold with effect of various capacitor value on Hold circuitry. Natural sampling Flat-top sampling. Aliasing effect. On board 6 different sampling frequencies. Duty cycle variation in steps of 10% upto 90%. 1Khz, 2KHz on board synchronized sine wave generator. Low pass butterworth filters Various test points provided on board. Switch Faults. Sampling Clock : Internal Frequency : 2 Khz, 4khz, 8khz, 16khz, 32khz, And 64khz. Duty Cycle : 10-90% Selectable In Steps Of 10%. Sampling Methods: Natural Sampling circuit. Sample and Hold circuit. Flat Top Sampling circuit. Reconstruction: 2nd order and 4th order low pass butterworth filters with 3.4KHz cut-off frequency. Switch Faults: 7 Switch Faults are provided on board to study different Interconnection : 2 mm Banana Socket, Two 4 Pin Connectors for Audio Input / Output Kit. Test Points : 24 Nos. test points are provided on board to observe : GND, +5V, +12V, -12V. LIST OF EXPERIMENTS : Principles of Analog signal sampling and reconstruction. Effect of different sampling frequencies. Effect of varying the sampling frequency duty cycle. Study of 2nd order & 4th order low pass butterworth filters. Effect of Switch Faults. Voice Communication (OPTIONAL). ACCESSORIES : Red short links OPTIONAL : : 06 Nos. ON BOARD SIGNALS: SINE WAVE: Frequency : 1khz, 2khz. Amplitude : 0-5vpp. 09

2 DCL - 02 PAM TIME DIVISION MULTIPLEXING / DEMULTIPLEXING KIT Phase Locked Loop circuitry. Effect of Switch Faults. Voice Communication (OPTIONAL). Red short links : 15 Nos. DCL - 03 TDM PULSE CODE MODULATION KIT This kit facilitates students to perform experiments in the areas of Pulse Amplitude Modulation, Demodulation and Time Division Multiplexing of these signals. It provides facility to examine Sampling, Multiplexing, Demultiplexing and Signal Re-construction. 4 Channels for Analog Signal Multiplexing and Demultiplexing. Transmitter and Receiver synchronized through PLL. On-board Variable Sine Wave & DC level generator. 4th Order Butterworth filter for reconstruction. Various Test points provided on board. Switch Faults. ON-BOARD SIGNALS: Sine Wave: Frequency : 250Hz, 500Hz, 1 KHz, 2KHz Amplitude : 0-5 V D.C. Signal : 0-5 V Input Channels : 4 nos. Multiplexing : Time Division Multiplexing. Sampling Rate : 32KHz. Modulation : Pulse Amplitude Modulation Receiver Clock : Phase Lock Loop generates receiver clock and channel information. Low Pass Filter : 4 th order Butterworth filters (3.4 KHz cutoff). Switch Faults :8 switch faults are provided on board to study different Interconnection : 2 mm Banana Socket, Two 4 Pin Connectors for Audio Input / Output Kit. Test Points: 39 Nos. Test points are provided to observe various Principle of Time Division Multiplexing. Study of PAM Time Division Multiplexing / Demultiplexing. Study of TDM with synchronization. To study the use of a Threshold Level Comparator and This kit facilitates students to learn and experiment Pulse Code Modulation techniques. It provides two-channel Time Division Multiplexed Pulse Code Modulation in none, even, odd & hamming parity formate. It enables students to learn the basics of timing synchronization between the transmitter and receiver. PCM receiver is a separate kit. FEATURES : 2 channel TDM Pulse Code Modulation Transmitter kit. Real-time operation using fast mode or examination of data and control signal using LED s in slow mode. Parity selection : None, Even, Odd, Hamming. 4 Single Bit error option using switched fault mode. On-board Variable Sine Wave and DC Level generator. Various Test points provided on-board. Switch Faults. ON-BOARD SIGNALS: Sine Wave: Frequency : 500 Hz and 1 KHz. Amplitude : 0-4 Vpp. D.C. : 2 Nos. Amplitude : 0-5 V Clock Frequency : 240 KHz Frame Frequency : 8 KHz Input Channels : 2-Channel Time Division Multiplexed and 10

3 Pulse Code Modulated. Synchronization Signal : Pseudo-Random Bit Sequence Sync Code Generation. Serial Data Pattern : 14 bit PRBS & 14 bit Data. Parity Code Facility : Even, Odd, Hamming, None Parity. Modes Of Operation : Fast : 16KHz / channel. Slow : 0.088Hz (811ms) / channel. Switch Faults : 8 Switch Faults are provided on board to study different Interconnection: 2 mm Banana Socket, 4 Pin Connector for Audio Input Kit Test Points : 23 Nos. Test points are provided to observe various : GND, +5V, +12V, -12V. (Dual output terminals) Principles of Pulse Code Modulation Techniques. Study of 2 Channel Time Division Multiplexing and Pulse Code Modulation. Study Principle of Analog to Digital Converter & Digital to Analog Converter. Study of Pseudo Random Bit Sequence Generation. Study of Error Control Coding Technique using ODD Parity, EVEN Parity and HAMMING Parity. Study of Synchronization Techniques : Bit Synchronization. Frame Synchronization. Effect of Switch Faults. Voice Communication (OPTIONAL). Red Long Links Double Connector OPTIONAL : : 06 Nos. : 05 Nos. DCL - 04 TDM PULSE CODE DEMODULATION KIT This kit facilitates students to see decoding of original encoded signal sent through PCM Transmitter Kit. The receiver kit phase locks to the input pulse stream to derive clock information. Moreover, by the use of pseudorandom binary sequence, the synchronization between Transmitter and Receiver is established. This kit also provides single bit error detection & correction facility. 2 channel Time Division Multiplexed PCM receiver. Real-time operation using fast mode and examination of data and control signals decoding using LED s in slow mode. Low pass filters for reconstruction. Single bit error detection, when odd or even parity is selected in the transmitter. Single bit error detection and correction when Hamming code is selected in the transmitter. Various Test points provided on-board. Switch Faults. Input Channels: 2 Channel Time Division Multiplexed Pulse Code Modulation receiver. Receiver Clock: Generated by Phase Lock Loop. Parity Check Facility: Even, Odd, Hamming. Error Correction: Hamming Code. Low Pass Filter : 2 Nos. 4 th order Butterworth Filter, 3.4 KHz (Cut-off ). Switch Faults : 4 Switch Faults are provided on board to study different Interconnection: 2 mm Banana Socket, 4 Pin Connector for Audio Output Kit. Test Points: 25 Nos. Test points are provided to observe various : GND, +5V, +12V, -12V. Principles of Pulse Code Demodulation Study of 2 Channel Time Division Demultiplexing and Pulse Code Demodulation. Study Principle of Digital to Analog Converter. Study of PRBS Generator. Study of Error Control Coding Technique using ODD Parity, EVEN Parity and HAMMING Parity. Study of Synchronization Techniques. Bit Synchronization. Frame Synchronization. Effect of Switch Faults. Voice Communication (OPTIONAL). Uses accessories provided with DCL

4 DCL - 05 DATA CONDITIONING AND CARRIER MODULATION KIT Data coding techniques for Non-Return to Zero format. Data coding techniques for Phase Encoded format. Data coding techniques for Return to Zero format and Multi-Level Binary format. Amplitude Shift Keying Modulation technique. Frequency Shift Keying Modulation technique. Phase Shift Keying Modulation technique. Effect of Switch Faults. This kit facilitates students to learn different types of data formats such as Non-Return to Zero, Phase Encoded, Return to Zero and Multilevel Binary format which are used in Digital Transmission systems. It also covers the study of Carrier Modulation techniques like ASK, FSK & PSK. DCL-05 is a Transmitter kit where as DCL-06 is a Receiver kit. Data conditioning format: NRZ(L), NRZ(M), NRZ(S), Biphase (Manchester), Biphase (Mark), Biphase (Space), URZ, Alternate Mark Inversion (AMI). ASK, FSK, PSK Carrier modulation techniques. On-board Data simulator generates 8 bit variable NRZ - L patterns. On-Board synchronized three carrier sine waves. Various Test points provided on-board. Switch Faults. DATA SIMULATOR: On-board 8 bit variable NRZ-L pattern. Clock Frequency: 250KHz Data Format (coding): NRZ(Level), NRZ(Mark), NRZ(Space), Biphase (Manchester), Biphase (Mark), Biphase (Space), URZ, AMI. On-Board Carrier Sine Waves: 500KHz(0 deg.), 1MHz(0 deg.), 1MHz(180 deg). Carrier Modulation: ASK, FSK, PSK. Switch Faults: 4 Switch Faults are provided on board to study different Interconnection: 2 mm Banana Socket. One 4 Pin Connector for Audio Input Kit connection. Test Points: 23Nos. Test points are provided to observe various (Dual output terminals) Principle of data conditioning. Red Long Links Double Connector : 07 Nos. : 03 Nos. DCL - 06 DATA RE-CONDITIONING AND CARRIER DEMODULATION KIT This kit takes data stream from DCL-05 as Input and does Re-conditioning and Demodulation. This kit facilitates students to learn different types of Data Format Decoding to get the original NRZ-L data. It also covers study of Carrier De-modulation techniques. Data Re-conditioning format :NRZ(L), NRZ(M), NRZ(S), Biphase (Manchester), Biphase (Mark), Biphase (Space), Return to Zero (RZ), Alternate Mark inversion (AMI). ASK, FSK, PSK Carrier Demodulation techniques. Receiver clock generated by Phase-Lock Loop. Various Test points provided on board. Switch Faults. Data Format (decoding): NRZ(Level), NRZ(Mark), NRZ(Space), Biphase (Manchester), Biphase (Mark), Biphase (Space), RZ, AMI. 12

5 Carrier Demodulation: ASK, FSK, PSK. Receiver Clock: Generated by Phase-Lock Loop. Interconnection: 2 mm Banana Socket. 4-Pin Connector for Audio Output Kit. Switch Faults: 4 Switch Faults are provided on board to study different Test Points: 30 Nos. Test points are provided to observe various Principle of Data Re-conditioning. Data decoding techniques for Non-Return to Zero format. Data decoding techniques for Phase Encoded format. Data decoding techniques for Return to Zero format and Multi-Level Binary format. Amplitude Shift Keying Demodulation technique. Frequency Shift Keying Demodulation technique. Phase Shift Keying Demodulation technique. Effect of Switch Faults. Uses accessories provided with DCL-05 DCL - 07 DELTA / SIGMA DELTA / ADAPTIVE DELTA MODULATION / DEMODULATION KIT This kit facilitates students to study concepts of Delta Modulation techniques. It facilitates students to examine Delta, Sigma Delta & Adaptive Delta Modulation and Demodulation. Linear Delta Modulation and Demodulation. Sigma Delta Modulation and Demodulation. Adaptive Delta Modulation and Demodulation CVSD Modulation & Demodulation. μ-law Compander. Selectable five different sampling frequencies. Four different on-board Sine Wave Generator, and variable D. C. Signal. Facility for interfacing external signals. nd th 2 & 4 order Low Pass Butterworth Filters. Various Test and Monitoring points provided on-board. Switch Faults. TECHNICAL DCL SPECIFICATIONS: - 06 DATA RE-CONDITIONING AND ON-BOARD SIGNALS: CARRIER DEMODULATION KIT SINE WAVE: Frequency : 250Hz, 500Hz, 1 KHz, & 2KHz Amplitude : 0-4 Vpp D.C. : 0-5 V. Sampling: Clock : 8KHz, 16KHz, 32KHz, 64KHz and 128KHz. Duty cycle : 50%. Modulation Techniques: Delta Modulation, Sigma Delta Modulation, Adaptive Delta Modulation, CVSD Modulation. Compander: μ-law Compander and Expander. Voice Communication: Voice Link for above Modulation Techniques using External Audio Input & Output kit(optional). nd th Low Pass Butterworth Filter: 2 Order and 4 Order Low Pass Butterworth filter with cut-off frequency of 3.4KHz. Switch Faults: 8 Switch Faults are provided on board to study different Interconnection: 2 mm Banana Socket, Two 4-Pin Connectors for Audio Input / Output Kit. Test Points: 34 Nos. Test points are provided to observe various Delta Modulation & Demodulation. Slope Overload and Increased integrator gain. Sigma Delta Modulation and Demodulation. Adaptive Delta Modulation and CVSD. Compression & Expansion. Effect of Switch Faults. Voice Communication (Optional). Screw Driver : 12 Nos. 13

6 DCL - 08 PAM / PWM / PPM MODULATION / DEMODULATION KIT This kit facilitates students to study concepts of Pulse Modulation techniques such as Pulse Amplitude Modulation (PAM), Pulse Width Modulation (PWM) and Pulse Position Modulation (PPM). It provides students facility to examine Sampling, Modulation, Demodulation and Signal Reconstruction. Pulse Amplitude Modulation. Pulse Width Modulation. Pulse Position Modulation. Effect of Switch Faults. Voice Communication (OPTIONAL). Red short links Extra jumper caps : 08 Nos. : 03 Nos. DCL - 09 STUDY OF FRAMING AND MARKER WITH VOICE CODING KIT PAM (Flat Top Sampling). Three different on-board Sine Wave Generations. Pulse Width Modulation (with 4 different clocks). Pulse Position Modulation. Selectable two different sampling frequencies from on-board Pulse Generator. th 4 order Butterworth filter. Various Test/Monitoring points provided on-board. Switch Faults. ON-BOARD SIGNALS: SINE WAVE: Variable frequency : 1Hz to 30Hz, Amplitude : 0-2 Vpp Fixed frequency : 500Hz and 1KHz. Amplitude : 0-4 Vpp. Sampling: Internal sampling clock : 8KHz and 16KHz. Duty Cycle : 50 %. Modulation Techniques: Pulse Amplitude Modulation (with variable clock 8KHZ, 16KHz)., Pulse Width Modulation (with variable clock)., Pulse Position Modulation (with variable clock). Voice Communication: Voice Link for above Modulation Techniques using External Audio Input/Output Kit (Optional). Switch Faults: 8 Switch Faults are provided on board to study different Interconnection: 2 mm Banana Socket, Two 4 Pin Connector for Audio Input / Output Kit. Test Points: 29 Nos. Test points are provided on board to observe Principles of Pulse Modulation. This kit facilitates students to study concepts of Framing and Marker in Time Division Multiplexing, PCM Voice Coding using telephone handset and frequency response of CODEC. 8-Channel Time Division Multiplexing & Demultiplexing. On-board Sine Wave 1 to 10 KHz. LED indicators for individual channels & marker. Framing & Marker concept. PCM Voice Coding and Decoding. CODEC Response. Switch Faults. ON BOARD SIGNAL: SINE WAVE: Frequency : 1-10 KHz Amplitude: 0-2 Vpp Data Clock : 512KHz. Framing : Frame frequency of 8KHz. TDM : 8-channel One for Marker, One for Audio channel and 6 14

7 channels for data switches with LED indication. Modulation Techniques: Pulse Code Modulation using CODEC Motorola MC Marker Indication: 8 Bit marker switch at both Tx & Rx Section with LED indication for 8 bits in Rx Section. Switch Faults: 8 Switch Faults are provided on board to study different Interconnection: 2 mm Banana Socket, Two 4 Pin Connector for Audio Input / Output Kit. Test Points: 12 Nos. Test points are provided to observe various Study of Time Division Multiplexing. Study of Framing in Time Division Multiplexing. Study of Marker in Time Division Multiplexing. Study of PCM Voice coding and Frequency response of CODEC. Effects of Switch Faults. Voice Communication (OPTIONAL). : 05 Nos. Signal Attenuation : 0 to input value. Input Impedance : 600 ohms. Voltage Gain : 1 to 100. RC Filter : 3.4 KHz cut-off. Maximum Output Voltage : 5V. Supply Voltage : GND, +12V, -12V. AUDIO OUTPUT KIT: Input Impedance : 50 K. Output Voltage : Adjustable. Speaker : 8, 0.5 W. Supply Voltage : GND,+ 12 Volts. Study the operation of Noise Generator and Signal Attenuation Network. Study of Audio Amplifier. Voice Communication with various modulation techniques. Red Long Links Microphone Power cable Connectors DG-05 BINARY DATA GENERATOR KIT A I/O AUDIO INPUT / OUTPUT KIT This kit provides facility for Interfacing Audio Signal to any of the Digital Communication Trainer kits. The input module accepts audio signal from microphone. The signal after amplification is given to Digital Communication Trainer Kits which accepts external Analog signal. The output module accepts analog input signal from Digital Communication Trainer Kits. The built in power amplifier output drives a speaker providing the audio output. A volume control knob is provided to adjust the volume. AUDIO INPUT KIT: Noise Generator: White Noise Amplitude : 0 2 V p-p. DG-05 Binary data generator kit provides 8, 16, 24 bit variable data pattern output at various user defined clock frequencies. This kit is used to supply binary data pattern to any of digital kit requiring binary data pattern as input signal. This kit has the facility to take external clock signal as input source to generate data pattern. 8, 16, 24 bit binary data output User selectable clock Clock output provided as reference. Internal Clock Frequency : 125KHz, 250KHz, 500KHz. External Clock Frequency : 125KHz to 1MHz Data Generator : 8,16 &24 bit binary data. Inter Connection: 2mm banana socket : GND, +5V. Red Long Links : 04 Nos. 15

8 ADVANCE DIGITAL COMMUNICATION TRAINING LAB The new series of Advance Digital Communication Trainers (Model - ADCL) give ultimate and most advanced knowledge and experience in the field of digital communication. These modules are designed to give indepth knowledge of various advance digital modulation demodulation techniques like BPSK / DPSK / DEPSK / QPSK / QAM, DPCM, ADPCM etc., base band modulation transmission system in most simplified and enjoyable manner. The trainer kits are also supported with e-manual software for simplified and enjoyable training criteria. ADCL - 01 BPSK / DPSK AND DEPSK MODULATION / DEMODULATION KIT Differentially Encoded Phase Shift Keying Modulation / Demodulation technique. Effect of Switch Faults. Observation of noise effect in constellation diagram (Optional) Single Connector : 12 Nos. ADCL-04 Baseband Digital Transmission Trainer kit ADCL-01 Kit is designed to give indepth knowledge of various advance digital modulation techniques like BPSK, DPSK, DEPSK etc. On-board synchronized Sine Wave Signal Generator with two different phases On-board Data Generator Differential encoding BPSK, DPSK, DEPSK modulation / demodulation Bandwidth efficiency Switch faults Provision for interfacing baseband modulation trainer kit (Optional) for noise effect in constellation diagram Data Simulator: On board 8 bit variable NRZ-L pattern. Clock Frequency: 250KHz Data Format (coding): Differential Encoding On Board Carrier Sine Waves: 500KHz(0 deg.), 500KHz(180 deg.). Carrier Modulation: BPSK, DPSK, DEPSK. Switch Faults: 8 Switch Faults are provided on board to study different Interconnection: 2 mm Banana Socket. Test Points: 28 Test points are provided to observe various intermediate signals. Principles of Advance Digital Modulation techniques. Differential Encoding of Data. Binary Phase Shift Keying Modulation / Demodulation technique. Differential Phase Shift Keying Modulation / Demodulation technique. ADCL - 02 QPSK AND DQPSK MODULATION KIT ADCL-02 Kit is designed to give indepth knowledge of various Advance Digital Modulation techniques like QPSK, DQPSK, etc. On-board synchronized Sine Wave Signal Generator with four different phases On-board Data Generator Dibit coding Symbol coder QPSK and DQPSK modulation Switch faults Provision for interfacing baseband modulation trainer kit (Optional) for noise effect in constellation diagram Data Simulator: On board 8 bit variable NRZ-L pattern. Clock Frequency: 250KHz BIT, Bit Clock and Word Clock 16

9 Data Format (coding): Dibit Pair (I & Q), Differential Encoding of I & Q Bits On Board Carrier Sine Waves: 500KHz(0 deg.), 500KHz(90 deg.), 500KHz(180 deg.), 500KHz(270 deg.). Carrier Modulation: QPSK, DQPSK. Switch Faults: 4 Switch Faults are provided on-board to study different Interconnection: 2 mm Banana Socket. Test Points: 24 Test points are provided to observe various intermediate signals. Principles of Advance Digital modulation techniques. Dibit pair Data Coding technique of NRZ-L data format. Differential Encoding of I & Q Bits. Quadrature Phase Shift Keying Modulation technique. Differential Quadrature Phase Shift Keying Modulation technique. Effect of Switch Faults. Long Links Double Connector : 14 Nos. ADCL-04 Baseband Digital Transmission Trainer kit QPSK and DQPSK demodulation Bandwidth Efficiency Constellation Diagram Switch faults Receiver Clock: Generated by Phase-Lock Loop. Data Format (decoding): Dibit Pair (I & Q), Differential Decoding of I & Q Bits Carrier Demodulation: QPSK, DQPSK. Switch Faults: 4 Switch Faults are provided on board to study different Interconnection: 2 mm Banana Socket. Test Points: 24 Test points are provided to observe various intermediate signals. Principles of Advance Digital demodulation techniques. Observation of Constellation diagram. Study of Bandwidth Efficiency of QPSK & DQPSK. Quadrature Phase Shift Keying demodulation technique. Differential Quadrature Phase Shift Keying demodulation technique. Effect of Switch Faults. Observation of noise effect in Constellation diagram (Optional) Uses accessories supplied with ADCL-02 Kit ADCL - 04 BASE BAND DIGITAL TRANSMITTER KIT ADCL - 03 QPSK AND DQPSK DEMODULATION KIT ADCL-03 Kit is designed to give indepth knowledge of various Advance Digital demodulation techniques like QPSK, DQPSK etc. This kit takes input from ADCL-02 kit. ADCL-04 Base band digital transmitter kit is an Advanced Digital Communication trainer kit designed to learn the fundamentals of base band Digital transmission system including properties of Transmitter and Receiver filters, Pulse Amplitude Modulation of binary data, Inter Symbol Interference, band limiting, observation of eye pattern, Bit error rate measurement, study of coding operation like Scrambling and Unscrambling. Clock recovery through PLL Dibit decoding Symbol decoder Clock Generator PRBS Generator 17

10 Noise Source Bit Error Rate Measurement Eye Pattern Scrambler and Unscrambler PAM Band limiting Inter symbol interference Switch Faults Single Connector ADCL-05 QAM/DQAM MODULATION KIT Noise Generator : White Noise Source output Amplitude : 0 to 2Vpp. PRBS Generator : 16 Bit switch selectable. Clock rate : 16, 32, 64, 128, 256, 512 KHz, MHz. Bit Error Rate Meter : 4 Digit counters with 7 segment display drivers. Count up to Display : 4 Digit seven segment. Digital Modulation: Modulation technique : Pulse amplitude modulation. Internal sampling clock : 16 KHz to 1.024MHz. Duty cycle : 50%. Transmitter Filter : 1st order Butterworth filter. Selectable switch with five different bands. Receiver Filter : 1st order Butterworth filter. Selectable switch with five different bands. Coding Operation: Scrambler: 16 bit data pattern. Unscrambler : 16 bit data pattern. Switch Faults: 8 Switch Faults are provided on board to study different Test Points: 30 Test points are provided on board to observe Intermediate signals. Interconnections: 2mm Banana Sockets. Study of pulse amplitude modulation of Digital data for base band transmission. Study of data extraction and recovery in base band digital transmission. Study of transmission and reception of band limited pulse train in base band digital transmission system. Study of eye pattern. Observation and calculation of noise margin percentage. Observation and calculation of timing jitter. Measurement of bit error rate using binary data. Study of message Scramblers and Unscramblers. Effect of Switch Faults. Red Long Links Extra Jumper Caps : 12 Nos. ADCL-05 QAM/DQAM Modulation kit from ADCL series provides facility for students to learn concepts in QAM generation. It also allows study of different applications of the QAM in Digital Communication. On-board synchronized Sine Wave Signal Generator with four different phases On-board data generation Tribit coding Symbol coder 8-QAM / DQAM modulation Bandwidth efficiency Switch faults Provision for interfacing base band modulation trainer kit for noise effect in Constellation diagram(optional) TECHNICAL SPECIFICATION: Data simulator: On board 24-bit variable NRZ-L pattern Clock frequency: 250KHz Data format (coding): Tribit coding (I,Q&C), Differential Encoding On board carrier sine waves: 500KHz(O deg.), 500KHz(90 deg.), 500KHz(180 deg.), 500KHz(270 deg.) Carrier Modulation: 8-QAM/DQAM Switch Faults: 4 Switch Faults are provided on board to study different Test Points: Several Test points are provided on board to observe different signals. Interconnections: 2mm Banana Sockets. To study the elements of 8-QAM / DQAM system Tribit coding technique of NRZ-L data format. Differential Encoding of Data. 18

11 8-QAM Modulation technique. DQAM Modulation technique. Effect of Switch faults. Red Long Links : 20 Nos. ADCL-04 Baseband Digital Transmission Trainer kit Observation of constellation diagram. Study of bandwidth efficiency of 8-QAM/DAQM. 8-QAM Demodulation technique. DQAM Demodulation technique. Effect of Switch faults. Observation of noise effect in Constellation diagram (Optional) Uses accessories provided with ADCL-05. ADCL 07: DPCM AND ADPCM MODULATION / DEMODULATION KIT ADCL-06 QAM/DQAM DEMODULATION KIT ADCL-06 QAM/DQAM Demodulation Kit receives input from ADCL-05 kit. This kit provides understanding of QAM/DQAM demodulation technique. Clock recovery through PLL Tribit decoding Symbol decoder 8-QAM/DQAM demodulation Constellation diagram Switch faults Provision for interfacing base band modulation trainer kit for noise effect in Constellation diagram (optional) TECHNICAL SPECIFICATION: Receiver Clock: Generated by Phase-Lock Loop. Data Format (decoding): Tribit decoding (I, Q & C), Differential Decoding Carrier Demodulation: 8-QAM/DQAM Switch Faults: 4 Switch Faults are provided on board to study different Test Points: Several Test points are provided on board to observe different signals. Interconnections: 2mm Banana Sockets. Tribit decoding technique. Differential decoding of Data. ADCL-07 is an Advanced Digital Communication trainer kit designed to study the fundamentals of Differential Pulse Code Modulation, Adaptive Pulse Code Modulation and Demodulation Techniques, principles of Differential Pulse Code Modulation, such as Sampling, Quantizing and Coding can be studied. Differential Pulse Code Modulation (DPCM) is a technique of waveform coding, which involves the use of a predictor. Adaptive Pulse Code Modulation technique attempts to code signals without any knowledge about how the signal was created. On-board Signal Generation Different Clock Frequencies Sample & Hold Technique DPCM & ADPCM Modulation and Demodulation Quantization Error Provision for interfacing base band modulation trainer kit for noise effect in DPCM & ADPCM (optional) Provision for interfacing Audio Input Output trainer kit for Voice Modulation (optional) Switch faults Onboard Signals: Sine wave Frequency: 500Hz Amplitude : 0 to 4 Vp-p. Sampling Technique : Sample & Hold Sampling Frequency: 16KHz Data Clock : 64,128, 256, 512 KHz. Data transfer rate : 64,128, 256, 512 Kbps. ADC word length : 8 bits. 19

12 Modulation Techniques: DPCM and ADPCM. Channel : 1 channels Data Clock : 64, 256 & 512 KHz ( ADPCM) 64,128, 256, 512 KHz (DPCM) Channel operation : Full duplex. Coding : u-law. Input Receiver Clock : 64KHz to 512KHz. Switch Faults: 8 Switch Faults are provided on board to study different Interconnection: 2 mm Banana Socket. Test Points: Several Test points are provided to observe various Study of DPCM Modulation Technique. Study of ADPCM Modulation Technique. Study of DPCM Demodulation Technique. Study of ADPCM Demodulation Technique. Quantization noise in DPCM. Effect of Switch faults. Channel and noise effect in DPCM and ADPCM (Optional). To study voice communication through DPCM and ADPCM (Optional) : 06 Nos. ADCL-04 Baseband Digital Transmission Trainer kit A I/O Audio Input Output Kit 20