2G Interactive Module 01 Quiz Test your comprehension of Module 01. Simply answer the following 15 multiple choice questions by selecting the circle next to the letter of your choice for each question and pressing the Submit Answers button at the end of the Quiz when you are finished. Follow the link below each question to go back to the Module and review related material. The review material will appear in a new browser window, close that window to return to the Quiz.

Q1) Which technology was used in the first generation wireless cellular systems? a) FDMA b) TDMA c) FM d) CDMA Review Material for Question 1 Q2) What motivated service providers to seek new and improved technological transmission applications for second generation systems? a) Availability of excess frequency spectrum b) Excess capacity c) To obtain increased propagation coverage d) To accommodate the increased number of subscribers Review Material for Question 2 Q3) Which of the following was not a feature of the first major improvement in cellular transmission technology? a) Upgrade from FM technology to FDMA technology b) Use of a complex system of channelization with 30 kHz channels c) Use of cell sectored directive antennas and complex frequency reuse planning d) Increase the height of cellular atennas Review Material for Question 3 Q4) A second step to further increase system capacity is a digital access method called TDMA (Time Division Multiple Access). Using the same frequency channelization and reuse as FDMA analog but adding a time sharing element, the effective capacity is: a) Doubled b) Tripled c) Reduced by one third d) Unchanged Review Material for Question 4 Q5) A third step to further increase capacity and improve quality was the introduction of Code Division Multiple Access (CDMA). Which of the following is not a characteristic of CDMA? a) Frequency division in 1.25 MHz bandwidth b) Use of correlative codes to distinguish one user from another c) Can not use sectored antennas d) A single user's channel consists of a specific frequency combined with a unique code Review Material for Question 5 Q6) What are Pseudo-Random noise sequences, or P/N Sequences? a) P/N Sequences are known sequences which exhibit the properties or chracteristics of random sequences b) P/N Sequences can be used to logically isolate users on the same physical (frequency) channel c) P/N Sequences appear as random noise to everyone else, except to the transmitter and intended receiver d) All of the above Review Material for Question 6 Q7) How are P/N codes generated? a) With a Linear Shift Register b) With the Encoder c) With the Vocoder d) With the Data Burst Randomizer (DBR) Review Material for Question 7 Q8) What drives the input to the Linear Shift Register? a) The Modulator b) The Modulo 2 Adder c) The Reception Device d) The Interleaver Review Material for Question 8 Q9) What is the maximum length of a P/N Sequence generated by an N-stage Linear Shift Register? a) 2exp(N) -1 b) 3exp(N) -1 c) 2esp(N) +1 d) 3esp(N) +1 Review Material for Question 9 Q10) In IS-95, two types of Maximum-Length PN Sequences or PN Codes are used: The Short PN Code and the Long PN Code. What is the maximum length of the Short PN Sequence when the PN Code is generated with a 15-stage Linear Shift Register? a) 16,384 chips b) 32,768 chips c) 1,228,800 chips d) None of the above Review Material for Question 10 Q11) The Long PN Code is generated by a 42-stage Linear Shift Register. What is the maximum length of the Long PN Code? a) 1,228,800 chips b) 4.4 trillion chips c) 2.2 trillion chips d) 2,457,600 chips Review Material for Question 11 Q12) If the Long PN Code runs at a speed of 1,228,800 chips per second, what is the repetition cycle? a) 26.67 ms b) 440 ms c) 3 - 4 days d) 41 - 42 days Review Material for Question 12 Q13) What is meant by "Correlation of Sequences"? a) Making certain that two PN Sequences have the same number of ones and zeros b) The correlations of two Random variables X(t) and Y (t), is a "time-shift" comparison which expresses the degree of similarity or the degree of Likeness between two variables c) Making certain that one PN Sequence has not been shifted relative to the other d) Making certain that the maximum length of two PN Sequences are the same Review Material for Question 13 Q14) When corresponding bits from two sequences have the same parity (or match each other) it is called an Agreement "A". Likewise, when corresponding bits from two sequences do not have the same parity it is called a Disagreement "D". How is the Correlation value determined? a) Correlation Value = Total number of "A" + Total number of "D"                                                               2 b) Correlation Value = Total number of "A" - Total number of "D" c) Correlation Value = Total number of "A" ÷ Total number of "D" d) None of the above are correct Review Material for Question 14 Q15) In general, when are two sequences or Codes Ci(t) and Cj(t) said to be orthogonal? a) When their respective Normalized or averaged Auto-correlation Functions are equal to unity "1" at time-shift zero ( 0) b) When their Normalized Cross-correlation Function is averaged to zero over the code Length c) Both of the above are correct Review Material for Question 15

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