射频复习材料2.docx

1、射频复习材料2 Electrical, ElectronicsEngineering Department Student Number: _ Name: _UEENEEH076C. RF Technology 2. BankMulti-Choice.for Student Revision.Question No:1. (Refer to page 8 Harmonics Book 2 of 2).With respect to the “Nature of Digital Signals” define the following:(a) Fundamental frequency.(b)

2、 Odd Harmonic frequencies.(c) Even Harmonic frequencies.(d) Resultant frequency. Question No:2. (Refer to page 9. Digital Signals. Book 2 of 2). Define the characteristics of “Pulse coded modulation systems”. (eg. The relationship between Transmission Speed and Distance)Question No:3. (Refer to page

3、 11. Digital signals & transmission mediums. Book 2 of 2). With reference to the diagram above determine the following:(a) The type of “Line Code” represented.(b) The binary data represented. Question No:4. (Refer to page 13. Some of the codes available. Book 2 of 2). With reference to the diagram a

4、bove determine the following:(a) The type of “Line Codes” represented.(b) The binary data represented.(c) The advantages/disadvantages of each code.Question No:5. (Refer to page 13. Some of the codes available. Book 2 of 2). (Refers to Diagram No:4.)Use the following line codes to represent the Bina

5、ry code1000 0101 0000 0011: (a) Bi-Polar RZ. (b) Polar NRZ.(c) Manchester . (d) Differential Manchester.Question No:6. (Refer to page 15. Signal spectrum evaluation. Book 2 of 2). Define the characteristics of AMI line code that make it suitable for Pulse code modulation (PCM) systems.Question No:7.

6、 (Refer to page 15. Signal spectrum evaluation. Book 2 of 2). Define the characteristics of HDB3 line code that make it suitable for Pulse code modulation (PCM) systems.Question No:8. (Refer to page 16. PCM analogue to digital conversion. Book 2 of 2). With respect to PCM analogue to digital convers

7、ion define the following:(a) Sampling Rate (relationship to frequency component of the signal being sampled.)(b) Nyquist Frequency. Question No:9. (Refer to page 18. Encoding. Book 2 of 2). Given that an 10 bit code is used for the sampling size.(a) Define the maximum number of positive and negative

8、 excursions of the signal amplitude.Question No:10. (Refer to page 19. Digitization of telephone audio. Book 2 of 2). Given the highest frequency of an audio baseband signal is 3 KHz, the sampling frequency is 10 KHz and the data to be transferred is a 16 bit code with 65,536 possible combinations.C

9、alculate the data transmission speed for a standard telephone.Question No:11. (Refer to page 20. Book 2 of 2).Define the following:(a) Quantising Distortion.(b) Companding.(c) Compressed.(d) Expanded.Question No:12. (Refer to page 26. Examples (cable types). Book 2 of 2). Define the physical charact

10、eristics of the following cables:(a) RG6/U. (b) RG11/U.(c) RG59/U.Question No:13. (Refers to page 24. Book 2 of 2 .) (Refers to Diagram shown above.)Define the name and function of each layer of the “Coax Cable” shown above.Question No:14. (Refer to page 30. Connector types. Book 2 of 2). Define the

11、 type of connector, common use and the impedance of the connector shown above.Question No:15. (Refer to page 31. F Connector. Book 2 of 2). With respect to the “F” Type connector, define the following:(a) Impedance(b) Frequency(c) Advantages(d) Disadvantages(e) Common usesQuestion No:16. (Refer to p

12、age 30. Connector types. Book 2 of 2). Define the name and common use of the connector shown above.Question No:17. (Refer to page 33. TNC Connector. Book 2 of 2). Define the name and common use of the connectors shown above.Question No:17. (Refer to page 33. Motorola connector. Book 2 of 2). Define

13、the name and common use of the connector shown above.Question No:18. (Refer to page 33. UHF connector. Book 2 of 2). Define the name and common use of the connector shown above.Question No:19. (Refer to page 31. SMA connector. Book 2 of 2). (a) Define the name and common use of the connector shown a

14、bove.(b) Define the physical characteristics of this connector. (eg. Relative size/construction)(c) Define the electrical characteristics of this connector. (eg. Impedance/Frequency range)Question No:20. (Refer to page 32. SMB connector. Book 2 of 2). (a) Define the name and common use of the connec

15、tor shown above.(b) Define the physical characteristics of this connector. (eg. Relative size/construction)(c) Define the electrical characteristics of this connector. (eg. Impedance/Frequency range)Question No:21. (Refer to page 34. RCA connector. Book 2 of 2)Define the name and common use of the c

16、onnectors shown above.Question No:22. (Refer to page 35. TRS connector. Book 2 of 2). Define the name and common use of the connectors shown above.Question No:23. (Refer to page 38. Attenuators. Book 2 of 2). (a) Define the name and common use of the device shown above.(b) Define the electrical char

17、acteristics of this device. (eg max power rating)Question No:24. (Refers to page 56. DMM overall accuracy. Book 2 of 2). With respect to the “Digital Multi Meter” (DMM), define the following: (a) AC accuracy. (b) DC accuracy. (c) Frequency Range (eg AC measurements).(d) 4.5 Digits.Question No:25. (R

18、efer to page 51. Spectrum analyser. Book 2 of 2). Define the name and function performed by each section of the Block diagram shown above. Question No:26. (Refer to page 62. Digital storage oscilloscope (DSO). Book 2 of 2). Define the name and function performed by each section of the Block diagram

19、shown above. Question No:27. (Refer to page 48. RF Network Analyser. Book 2 of 2). Define the name and functions performed by the “Test Equipment” shown above.Question No:28. (Refer to page 48. RF Network Analyser. Book 2 of 2).Define the functions performed by the following RF Network Analysers:(a)

20、 Scalar Network Analyser (SNA).(b) Vector Network Analyser (VNA) (c) Large Signal Network Analyser (LSNA)Question No:29. (Refer to page 50. RF Spectrum Analyser. Book 2 of 2).Define the functions performed by a Radio Frequency Spectrum Analyser. FORMULAE SHEET.Bit Rate. Bit Rate = Samples per sec x

21、Number of bits per sample x 2 (for two channels (stereo)Data Transmission Speed.Data Transmission Speed = Number of bits per sample x Sample Rate.Nyquist Rate. Nyquist Rate (minimum) = 2 x highest frequency component of an audio signal.%Throughput = (Number of Data bits Total number of bits transmit

22、ted per character) 100%Throughput = (Data (Data + Start bit + Parity bit (if used) + Stop bit/s) 100Shannons Law Shannons Law = 3.32 x BW x log10( 1 + S/N) bpsWhere: bps is the maximum transfer speed in bits per secondBW is the bandwidth of the channel in Hz (Hertz)S is the power of the signalN is the power of the noise on the channel