1 / 149

LEARNING OBJECTIVES

LEARNING OBJECTIVES. 1. State four functions of a telephone set. 2. Label a block diagram of a telephone set. 3. Describe the electrical differences between pulse and tone dialing. 4. Describe the structure of the local telephone exchange. 5. Describe each of the BORSCHT functions.

mikasi
Télécharger la présentation

LEARNING OBJECTIVES

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. LEARNING OBJECTIVES 1. State four functions of a telephone set. 2. Label a block diagram of a telephone set. 3. Describe the electrical differences between pulse and tone dialing. 4. Describe the structure of the local telephone exchange. 5. Describe each of the BORSCHT functions. 6. Define “IDDD World Numbering Plan.” 7. Explain the differences between the telephone exchange classifications. 8. Describe the electrical characteristics of PAM, PDM, PCM, and DM. 9. Describe the advantage of companding. 10. State the companding technique used in the United States and Europe. 11. Analyze attenuation, delay, and line conditioning on a voice-channel. 12. Interpret attenuation/ delay charts for conditioned lines. 13. Prepare a brief definition of multiplexing and demultiplexing. 14. Describe the characteristics of SDM, FDM, TDM, and STDM techniques. 15. Describe the structure of the analog common carrier hierarchy. 16. Describe the structure of the digital common carrier hierarchy. 17. Explain the services offered through T1, T2, T3, and T4 connections. 18. Label a block diagram of the T1 frame format.

  2. LEARNING OBJECTIVES (continued) 19. Prepare a brief definition of CSU/DSU. 20. State the advantages of superframes and extended superframes over standard T1 frames. 21. Administer change controls by adding new telephone equipment. 22. Design the network by identifying the availability of local T1 access. 23. Describe the electrical characteristics of a T1 signal. 24. State two types of acceptable T1 connectors. 25. Ensure appropriate resources are available for implementing T-Carrier access. 26. Describe the services available with a SONET connection. 27. Describe the frame format of a SONET STS1. 28. Define SONET terms such as virtual tributary, terminating multiplexer, regenerator, and add/drop multiplexer. 29. While planning a customer’s job, study technology options, pro and con. 30. Identify the technical capabilities of T-Carrier, SONET, and Multiplexing.

  3. Figure 9-1: Frequency Response of Voice Channel

  4. Figure 9-2: Producing Amplitude Modulation

  5. Figure 9-3: AM Modulation Envelope

  6. Figure 9-4: Frequency Modulation

  7. Using Carson’s rule, bandwidth is calculated by: BW = 2(DFc + Fm) where Fc is the deviation produced by the modulating signal, and Fm is the frequency of the modulating signal.

  8. The bandwidth of the FM signal is: BW = 2(DFc + Fm) BW = 2(1 kHz + 1 kHz) BW = 2(2 kHz) BW = 4 kHz

  9. Figure 9-5: Phase Modulation

  10. Figure 9-6: Equivalent Two-Conductor Cable Circuit

  11. Table 9-1: Terminating Resistance Guide

  12. For any length of RG-58 coaxial cable, the characteristic impedance can be approximated by: L/C Zo = 

  13. This means the RG-58 cable will behave as any circuit with a capacitor, and inductance, and a 50-ohm load. It will exhibit phase-shifts and time constants as in any RCL circuit. Zo = _________ 73 x 10-9 295 x 10-12 Zo = 49.745 ohms

  14. Figure 9-7: Effects Of Intersymbol Interference on Data Signals (a) (b) (c)

  15. Figure 9-8: Evaluating the Eye Pattern with an Oscilloscope for ISI Distortion (a) (b)

  16. Figure 9-9: Equalizer Block Diagram

  17. The following illustrates examples of common logs: 104 = 10,000 = a log of 4 103 = 1,000 = a log of 3 102 = 100 = a log of 2 101 = 10 = a log of 1 100 = 1 = a log of 0 10–1 = .1 = a log of –1 10–2 = .01 = a log of –2 10–3 = .001 = a log of –3 10–4 = .0001 = a log of –4

  18. Common logs are integrated with decibels in the following formula: dB = 10 log (Po/Pi) where Po = Power out and Pi = Power in.

  19. An amplifier has an input power of 10 mW (milliwatts) and a power out of 20 mW. Calculate the gain in decibels. dB = 10 log (Po/Pi)

  20. An amplifier has an input power of 10 mW (milliwatts) and a power out of 20 mW. Calculate the gain in decibels. dB = 10 log (Po/Pi) dB = 10 log (20

  21. An amplifier has an input power of 10 mW (milliwatts) and a power out of 20 mW. Calculate the gain in decibels. dB = 10 log (Po/Pi) dB = 10 log (20 mW/10 mW)

  22. An amplifier has an input power of 10 mW (milliwatts) and a power out of 20 mW. Calculate the gain in decibels. dB = 10 log (Po/Pi) dB = 10 log (20 mW/10 mW) dB = 10 log (2)

  23. An amplifier has an input power of 10 mW (milliwatts) and a power out of 20 mW. Calculate the gain in decibels. dB = 10 log (Po/Pi) dB = 10 log (20 mW/10 mW) dB = 10 log (2) dB = 10 (.3)

  24. An amplifier has an input power of 10 mW (milliwatts) and a power out of 20 mW. Calculate the gain in decibels. dB = 10 log (Po/Pi) dB = 10 log (20 mW/10 mW) dB = 10 log (2) dB = 10 (.3) dB = 3

  25. The power received through a transmission line is .25 mW. Using decibels, evaluate the performance of the line if the power at the transmitter is 1 mW. dB = 10 log (Po/Pi)

  26. The power received through a transmission line is .25 mW. Using decibels, evaluate the performance of the line if the power at the transmitter is 1 mW. dB = 10 log (Po/Pi) dB = 10 log (.25 mW/1 mW)

  27. The power received through a transmission line is .25 mW. Using decibels, evaluate the performance of the line if the power at the transmitter is 1 mW. dB = 10 log (Po/Pi) dB = 10 log (.25 mW/1 mW) dB = 10 (–.6)

  28. The power received through a transmission line is .25 mW. Using decibels, evaluate the performance of the line if the power at the transmitter is 1 mW. dB = 10 log (Po/Pi) dB = 10 log (.25 mW/1 mW) dB = 10 (–.6) dB = –6

  29. What is the value of the signal strength? dB = 10 log (Po/Pi)

  30. What is the value of the signal strength? dB = 10 log (Po/Pi) –6 dB = 10 log (x/1 mW)

  31. What is the value of the signal strength? dB = 10 log (Po/Pi) –6 dB = 10 log (x/1 mW) –.6 dB = log (x/1 mW)

  32. What is the value of the signal strength? dB = 10 log (Po/Pi) –6 dB = 10 log (x/1 mW) –.6 dB = log (x/1 mW) .25 = x/1 mW

  33. What is the value of the signal strength? dB = 10 log (Po/Pi) –6 dB = 10 log (x/1 mW) –.6 dB = log (x/1 mW) .25 = x/1 mW .25 mW = x = Po

  34. A power amplifier has 5-dB gain referenced to 6 mW. What is the output power? dB = 10 log (Po/Pi)

  35. A power amplifier has 5-dB gain referenced to 6 mW. What is the output power? dB = 10 log (Po/Pi) 5 dB = 10 log (Po/6 mW)

  36. A power amplifier has 5-dB gain referenced to 6 mW. What is the output power? dB = 10 log (Po/Pi) 5 dB = 10 log (Po/6 mW) .5 dB = log (Po/6 mW)

  37. A power amplifier has 5-dB gain referenced to 6 mW. What is the output power? dB = 10 log (Po/Pi) 5 dB = 10 log (Po/6 mW) .5 dB = log (Po/6 mW) Inverse log .5 = Po/6 mW

  38. A power amplifier has 5-dB gain referenced to 6 mW. What is the output power? dB = 10 log (Po/Pi) 5 dB = 10 log (Po/6 mW) .5 dB = log (Po/6 mW) Inverse log .5 = Po/6 mW 3.16 = Po/6 mW

  39. A power amplifier has 5-dB gain referenced to 6 mW. What is the output power? dB = 10 log (Po/Pi) 5 dB = 10 log (Po/6 mW) .5 dB = log (Po/6 mW) Inverse log .5 = Po/6 mW 3.16 = Po/6 mW 18.96 mW = Po

  40. A data signal is permitted no more than 1 dB of attenuation, or loss, from transmitter to receiver. You measure the transmitter power at 24.2 mW and the power received at 19.5 mW. Is this an acceptable amount of attenuation? dB = 10 log (Po/Pi)

  41. A data signal is permitted no more than 1 dB of attenuation, or loss, from transmitter to receiver. You measure the transmitter power at 24.2 mW and the power received at 19.5 mW. Is this an acceptable amount of attenuation? dB = 10 log (Po/Pi) dB = 10 log (19.5 mW/24.2 mW)

  42. A data signal is permitted no more than 1 dB of attenuation, or loss, from transmitter to receiver. You measure the transmitter power at 24.2 mW and the power received at 19.5 mW. Is this an acceptable amount of attenuation? dB = 10 log (Po/Pi) dB = 10 log (19.5 mW/24.2 mW) dB = 10 log (.806)

  43. A data signal is permitted no more than 1 dB of attenuation, or loss, from transmitter to receiver. You measure the transmitter power at 24.2 mW and the power received at 19.5 mW. Is this an acceptable amount of attenuation? dB = 10 log (Po/Pi) dB = 10 log (19.5 mW/24.2 mW) dB = 10 log (.806) dB = 10 (–.0936)

  44. A data signal is permitted no more than 1 dB of attenuation, or loss, from transmitter to receiver. You measure the transmitter power at 24.2 mW and the power received at 19.5 mW. Is this an acceptable amount of attenuation? dB = 10 log (Po/Pi) dB = 10 log (19.5 mW/24.2 mW) dB = 10 log (.806) dB = 10 (–.0936) dB = –.936

  45. At a minimum, the telephone set: Initiates use of the telephone system when the handset is lifted. 1

  46. Table 9-2: Typical SNRs of Communication Channels

  47. The signal-to-noise ratio is a measure of the desired signal power to the noise signal power at the same point in a circuit. It’s expressed mathematically as: SNR = Ps/Pn where Ps = the power of the desired signal and Pn = the power of the noise. It’s often expressed in decibels as: SNR = 10 log (Ps/Pn)

  48. For example, if the SNR is to be determined at the output of a transmitter, and the signal level is determined to be 2 mW and the noise is 500 mW, the SNR is: SNR = 2 mW/.5 mW SNR = 4

  49. or, as a decibel: SNR = 10 log (Ps/Pn) SNR = 10 log (2 mW/.5 mW) SNR = 10 log (4) SNR = 10 (.602) dB SNR = 6 dB

More Related