The numbers in parentheses indicate the number of marked items (1
mark each).

			      Labs

Lab 1 Pre-Lab (3)

- name, date and title
- table showing bit values and voltages
- C program

Lab 1 Report (4)

- audacity screen capture
- 'scope screen capture
- hexedit screen capture
- corrected C listing


Lab 2 Pre-Lab (4)

- correct voltages (>3V or <-3V)
- correct file size = 160 + 160x# characters
- C program writes correct values (0x0000 and 0x3fff) 
- C program writes bytes in correct order (LS byte first)

Lab 2 Report (3)

- terminal screen capture
- 'scope screen
- program listing


Lab 3 Pre-Lab (3)

- C, L per meter for Cat 5 cable
- C and L values for 1 and 5 meters of cable
- a spreadsheet with 6 columns

Lab 3 Report (4)

- table includes equation for L=1/(4 pi^2 f^2 C)
- includes calculated result for capacitance/m ~50pF/m
- a comparison of C and H per meter to published values

Lab 4 Pre-Lab (3)

- V/6 volts/division
- (3/f)/14 or 3/(14xf) or 0.21/f us/division
- RMS measurement

Lab 4 Report (3)

- reasonably well-formatted graph of amplitude and phase response
- roll-off of about 12~dB/octave
- unique spreadsheet included (not a copy of someone else's)

Lab 5 Pre-Lab (2)

- 2(c) probability density has two values with voltage = -2 and 1
- 4(b) 10/256 = 39mV

Lab 5 Report (4)

- plot of Gaussian noise waveform
- 3 screen captures
- histograms for sine and noise
- RMS voltage from sine wave histogram ~= measured value


Lab 6 Pre-Lab (3)

- q2: > returns vector/matrix of 1's or 0's if LHS greater the RHS
    (right hand side)
- q3: 2 rows, 3 columns
- q8: at 1 MS/s and 10 samples/bit the bit rate is 100 kb/s

Lab 6 Report (3)

- 3 screen captures
- 3 correct spectra 
- frequency of nulls is 100 kHz for NRZ, 200 kHz for Manchester

Lab 7 Pre-Lab (3)

- 2(a): 2 tx, 2rx
- 2(b) for transmitter: TTL levels (0-5V) on inputs, approx +/-10V on outputs
- 6: max 30V/us

Lab 7 Report (3)

- 1. reasonable mark/space voltages (~9V)
- 2. reasonable output impedance measurement (>300 ohm)
- 4. slew rate measurement (reasonable data and result <30V/us)

Lab 8 Pre-Lab (2)

- spreadsheet
- graph

Lab 8 Report (3)

- 'scope noise screen capture
- table with reasonable range of BER (~1e-2 to ~1e-6)
- graph with reasonable agreement between theory and measurement

Lab 9 Pre-Lab (1)

- screen capture of hexedit with a reasonable approximation to an
  Ethernet packet

Lab 9 Report (5)

- hexedit screenshot with a correct packet (including name,
  padding and CRC)

- 'scope screen capture showing both TD+/TD- and the differential
  voltage during the preamble

- wireshark capture showing name

- answer to question (2): frequency = 5 MHz

- answer to question (4): preamble and CRC not shown


			   Assignments

Assignment 1 (12)

Q1: 

(c) equation including truncation or rounding
(d) correct values (quantized or not)

Q2:

(b) number of bytes (typically 3 per character)
(d) code points (plausible values)

Q3:

- description of method used
- entropy ~= 4 bits/character

Q4: 

(a) about ~= 11,600 seconds
(b) throughput ~= 6900 bps

Q6:

(a) a valid IC part number

Q7:

- a length of open-circuited transmission line
- l ~= 0.3m

Q8:

- Ae ~= 1 sqm


Assignment 2 (5)

Q1: curve should have maxima/minima equally above/below 1 with
    maxima between 1.1 (a=0, x=0.1) and 1.8 (a=9, x=0.82) at f=0
    and should have minima every 500 Hz (b=0, tau=2ms) to 153 Hz
    (b=9, tau=6.5ms) (a and b are middle two digits)

Q2: 500ns

Q3: 1.98 MHz

Q4: 65%

Q6: 84%

(Question 5 was not marked because question does not actually ask
you to run the program!)

Assignment 3 (11)

Q1: prints approximately 1% or 0.01 or 14,000

Q2: 67%

Q3: -6dB at 129 kHz

Q4: graph looks (by eye) correct for alpha

Q5: 256us = 512 samples (or 276 = 552)

Q6: p<3% and p>97%

Q7: (a) 4.4 Mb/s
    (c) BER = 4E-6

Q8: spectrum shows peak at about 40 kHz

Q9: correct flags and escaping

Q10: differential voltage is +/-5 V

common mistakes: [copying a] program that calculates the number
of frames with <3 errors.  capacity calculated using S/N as a
voltage ratio.  questions not answered.  arithmetic/algebra
errors.  wrong frequency axis values.  BER given in units of
errors per second (not marked as an error).

Assignment 4 (8)

Q1: E4

Q2: (b) dmin=3
    (c) codeword C (CDA) transmitted

Q3: (a) A=(1)1[0], B=(1)0[1] {(given)answer[next]}

Q4: CRC=0001

Q5: any reasonable OUI lookup

Q6: (b) Ethertype=ARP
    (c) payload is 28 bytes


			  Mid-Term Exam

One mark was assigned for each of the following essential
elements of a correct solution:

Question 1 (3)

- computing log(probability) for each message
- computing the weighted sum 
- right answer

Question 2 (4)

- correct bit and baud rate
- correct bit order and polarity
- correct hex value
- correct character

Question 3 (3)

- convert from AWG to mm
- use correct equation for Z0
- right answer

Question 4 (3)

- type of channel (LPF)
- bandwidth
- signal level


			   Final Exam

Question 1 (5)

- log2(4)/1E-6 = 2Mb/s
- 1/1E-6 = 1MHz
- correct formula for calculating entropy
- correct answer (1.85 [Mb/s])
- 1/0.5E-6 = 2 MHz

Question 2 (4)

- correct bit values and order (2) (0x97 and 0xE3)
- correct bit rate (9600 and 19200)
- polarity, type (odd)

Question 3 (4)

- used Friis formula
- solved for distance
- correct wavelength and conversion from dB
- correct answer (265m or 839m)

Question 4 (3)

- correct CRC length
- correct calculation of remainder
- correct conclusion about errors from result

Question 5 (8)

- answers: 2, 6, 1/3 (by inspection) (0.5 if partially right)
- calculations of distances
- answer = 3
- dmin-1=2
- (dmin-1)/2=1
- yes, not a valid c/w
- 101100 or 000110
- yes, anything is possible

Question 6 (10)

- use Stop and Wait; explanation (2)
- output on RxD->DCE, on TxD->DTE; null modem (2)
- 100m; 100/2e8= 0.5us (2)
- half of bit rate (500kHz or 1MHz); minimum is a brick-wall response (2)
- transformer
- THD