The numbers in parentheses indicate the number of marked items (1 mark each).
Pre-Labs
Pre-Lab 1 (3)
- sum of digits
- period
- a reasonable attempt at a C program
Pre-Lab 2 (4)
- correct title, etc
- RMS voltage calculation (3.1V)
- probability density function (two impulses with values 0.3 and 0.7)
- step size (~2mV)
Pre-Lab 3 (2)
- spreadsheet printout
- with formulas
Pre-Lab 4 (3)
- C program
- high/low levels
- baud and sample rates correct as per student ID
Pre-Lab 5 (3)
- original MAX-232 schematic
- purposes of MAX-232 charge pumps
- maximum bit rate calculation
Pre-Lab 6 (1)
Pre-Lab 8 (1)
Pre-Lab 10 (2)
- purpose of filter
- how to show more details about a protocol layer
Labs
Lab 1 (3)
- cover page
- audacity and 'scope screen captures for your number
- a program listing which would generate the above waveform
Lab 2 (3)
- plots of waveforms
- histograms
- table comparing RMS measured and computed from historgrams
Lab 3 (2)
- spreadsheet table showing calculations
- characteristic impedance
Lab 4 (2)
Lab 5 (3)
- MAX 232 output impedance measurement
- RS-422 waveform capture
- RS-422 slew rate
Lab 6 (3)
- C listing
- graph
- roll-off (matching graph)
Lab 7 (4)
- schematic
- noise plot
- screen capture
- BER vs SNR plot
Lab 8 (2)
Lab 9 (5)
- packet contents in hex
- 'scope screen capture
- wireshark output
- preamble frequency
- portions of frame not shown
Lab 10 (5)
- Intro q2: GET to OK delay 50 to 100 ms
- IP q1: your IP address is 142.232.x.y
- IP q2: ICMP
- IP q5: identification field, header checksum changes
- IP q6: destination address must stay fixed, TTL must change
Assignments
Assignment 1
Marked out of 7. One mark each for:
- Q1: 6.5 bits/word
- Q1: 21.6 bps
- Q2: CallCatinHat
- Q6: program that differentiates between Unicode and ASCII
- Q8: d=0.5cm
- Q8: D=1.2cm
- Q9: Zo=63 ohm
Assignment 2
Marked out of 7. One mark each for:
- Q1 (b) dlm=0 dll=6
- Q1 (c) LSR bit 3
- Q2 (a) 5.38 MHz
- Q3 (a) at generator side
- Q4 (a) 100mV
- Q5 52~kHz (or 62 kHz)
- Q6 (a) group delay = 0.5 and 1 ms
Assignment 3
- Q1: total change of 4pi over 0 to 4kHz (4 peaks)
- Q2: slew rate ~60 V/us (or MV/s)
- Q3: 0.5V
- Q4: 1dB loss
- Q5: 512 samples/symbol
- Q6: polarity insensitive
- Q9: CRC = 100
Assignment 4
- Q1a: 63 bits
- Q2: crc=0
- Q3b: cisco-linksys
- Q4: checksum=7bb3
- Q5: 255.224.0.0
- Q6: correct 1, detect 2
- Q7: 166kb/s
Mid-Term Exam
One mark was assigned for each of the following:
Q1
- right bit order (0x69, not 0x96)
- right polarity of bits (H=0)
- right answer (0x69)
- can't tell about polarity: last 'bit" could be parity or a stop bit
Q2
- there are 4 different waveforms so each one carries log2(4)=2 bits of data
- bit rate = 2 bits/3ms = 666 bps
- symbol rate = 1 symbol/3ms = 333 symbols/second
- baud rate = 3 level transitions/symbol * 333 symbols/second = 1000 baud
Q3
- used right values: 50E3 W (or 77dBm), GT=GR=2 (or 3dB), d=1E5m
- computed wavelength = 3m
- used correct equation (Friis)
- right answer (114E-6W)
Q4
- values for mean (12) and s.d. (1)
- normalized threshold value (t=-2)
- correct approximation calculation (or accurate value from calculator)
- right answer (2%)
Q5
- THD
- explanation that only one sine wave used (IMD requires two)
- harmonics of 1kHz (2, 3, ...)
Final Exam
One mark was assigned for each of the following. Numbers in parentheses are the total marks for each question.
Q1 (4)
- probabilities
- entropy calculation method
- entropy result
- information rate result
Q2 (6)
- bit values
- bit order
- start/end/data bits
- polarity
- levels
- time axis
Q3 (6)
- equation for e_r
- value of e_r
- equation for Zo
- equation for v
- solution
- answer
Q4 (3)
- use of capacity equation
- calculation of SNR & capacity
- result
Q5 (4)
- start flag
- end flag
- bit-stuffing
- data correct
Q6 (4)
- correct sum
- add MS to LS word
- convert to binary
- bit-complement
Q7 (4)
- one mark per correct answer
Note: the final was out of 31 (not 30).