Marks were assigned as follows.
Lab 1 Pre-Lab
Marked out of 3; 1 for each of:
- sum of digits
- samples/bit=8
- a C program that outputs two different values
Lab 2 Pre-Lab
Marked out of 3; 1 for each of
- a spreadsheet
- with 6 columns
- including name, value and units
Lab 3 Pre-Lab
Marked out of 3; 1 for each of
- your name in the code
- correct measurement loop termination condition
- correct Sleep(ms) function call
Lab 4 Pre-Lab
Marked out of 4; 1 for each of:
- Q1
- mean of triangle wave
- rms voltage of triangle wave
- Q2: RMS voltage
- Q3: number of levels
Lab 5 Pre-Lab
Marked out of 6; 1 for each of:
- identification including name, lab, & date
- Q1: correct bit rate (9600 bps)
- Q2: difference=0
- Q2: gain=5x
- C program
- C program has 2 loops (one for characters, one for bits)
Lab 6 Pre-Lab
Marked out of 5; 1 for each of:
- MAX 232 schematic including 4 capacitors
- function of charge pumpt is to increase and invert supply voltage
- maximum slew rate is 30V/us
- 3486/3487 schematic showing enables tied high
- rise time >20ns; maximum bit rate is 5 MHz
Lab 8 Pre-Lab
Marked out of 4; 1 for each of:
- correct amplituder
- correct phase increments
- correct samples/bit
- reasonable C code
Lab 9 Pre-Lab
Marked out of 1; 1 for each of:
Lab 10 Pre-Lab
Marked out of 4; 1 for each of:
- top-level protocol (1)
- display only packets matching filter expression (1)
- click on '+' or '-' (1)
- bottom window (1)
Lab 1 Report
Marked out of 5; 1 for each of:
- identification including name, lab, & date
- correct bits and voltage levels
- in the form of a table
- 'scope screen capture
- Audacity screen capture
Lab 3 Report
Marked out of 8; 1 for each of:
- identification including name, lab, & date
- corrected C code (full listing)
- plots of magnitude and phase response, correctly formatted (2 marks)
- answers to the 3 questions (3 marks, 1 each question)
- spreadsheet (submitted to the dropbox in Excel format, not just the data or just the graph)
Lab 4 Report
Marked out of 10; 1 for each of:
- CSV, Excel and PDF files (3 marks)
- identification including name, lab, & date
- plot of first 2000 samples
- 3 histograms (3 marks)
- table comparing RMS values from DMM and computed from samples
- computed results that match measurements
Lab 5 Report
Marked out of 4; 1 for each of:
- identification including name, lab, & date
- Teraterm & 'scope screen captures (2 marks)
- updated C code
Lab 6 Report
Marked out of 6: (missing result: -1, suspicious results: -0.5)
For RS-232:
- - mark/space volages ~+/-10V: 1
- - output impedance >700ohm: 1
- - slew rate <30V/us: 1
For RS-422
- - independent screen captures: 1
- - differential screen capture (should be +ve and -ve): 1
- - measured a higher bit rate: 1
Lab 7 Report
Marked out of 5; 1 for each of:
- schematic
- spreadsheet with approximately correct measurements
- spreadsheet with approximately correct predictions
- plot of BER vs SNR
- plot of noise
Lab 8 Report
Marked out of 4; 1 for each of:
- identification
- program listing
- TeraTerm screen capture with output matching code
- 'scope screen capture
Lab 9 Report
Marked out of 3; 1 for each of:
- identification
- schematic
- correct simulation screen capture
Lab 10 Report
Marked out of 5; 1 for each of:
- identification
- IP address of gaia.umass.edu
- captured packet
- number of bytes in header
- destination IP address is constant
Assignment 1
Marked out of 4; 1 for each of:
- Q2: 0627
- Q3: 3 bytes,
- Q3: E7 8C B4
- Q4: 4C2
Assignment 2
Marked out of 5; 1 for each of:
- Q1(e): Zo=74 Ohms
- Q3: length ~= 560m
- Q4: a correct equation
- Q5(a): correct equation
- Q5(e): correct equation
Assignment 3
Marked out of 11; 1 for each of:
- Q1: 1 for each correct waveform (total of 3)
- Q2(a) approx. 1 kHz
- Q2(c) approx. 1 kHz
- Q2(e) approx. 0.2 dB
- Q3(a) 3dB (2)
- Q4 1 mark for 2 impulses, 1 mark for delays of 2 & 3 km (or 10 and 15 us)
- Q5(a) 0.25
- Q5(b) 5%
Assignment 4
Marked out of 9; 1 for each of:
- Q1a: pins 3,6
- Q1e: RI and DCD
- Q2: for AT
- Q3: 1 each ffor 2X, ~1.4X
- Q4: 1 each for 8kHz, 56kb/s
- Q5: 1 each for 30.72MHz, 1.4km
Assignment 5
Marked out of 12; 1 for each of:
- Q2:
- 500 ohm resistor in series
- 125 ohm resistor in parallel
- Q4:
- flags
- correct bit stuffing
- Q5:
- Manchester symbols
- correct encoding
- Q6:
- (d) Dmin = 4
- (e) detect Dmin-1
- (f) correct floor((Dmin-1)/2)
- (i) cannot correct or either codeword
- Q7:
- CRC length = 4
- CRC = 0111
Mid-Term Exam
Marked out of 15; marks awarded as follows:
- Q1: 2 marks: 1 for using the correct method (find number of data bits and divide by duration); 1 for correct answer
- Q2: 5 marks:
- (a): 1 for correct answer
- (b): 1 for correct method (converting power to/from voltage, taking ratio/difference to find gain); 1 for correct answer
- (c): 1 for correct answer
- (d): 1 for correct answer
- Q3: 3 marks: 1 for using correct equation, 1 for solving for D; 1 for correct answer
- Q4: 5 marks
- (a) 1 for using capacity theorem; 1 for solving for signal power; 1 for correct answer
- (b) 1 for using twice the bandwidth; 1 for correct answer
Final Exam
Marked out of 27; marks awarded as follows:
- Q1: 1 for 2 bytes, 1 for each byte
- Q2: 1 for start/stop bits, 1 for parity=0, 1 for bit order, polarity and value, 1 for axis labels
- Q3: 1 for VF, 1 for v, 1 for L, 1 for Zo
- Q4: 1 for using Shanon capacity, 1 for converting dB to a ratio, 1 for answer
- Q5: 1 for stuffing or not, 2 for correct values
- Q6: 1 for converting polynomial to bits, 1 for zero-extending data with 2 bits and doing division, 1 for identifying remainder as CRC
- Q7:
- (a) 1 for channel bit rate, 1 for throughput
- (b) 1 for stop-and-wait
- (c) 1 for distance
- (d) 1 for NO, 1 for YES
- (e)1 for FEXT only
- (f) 1 for twice, 2X or 2:1