[Advanced Communication System] Exams Solved

8/16/2019 [Advanced Communication System] Exams Solved

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Final 2013

i-


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ii-


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Final 2012

Note 1, pages 19-22, 26-35

1-

Small-Scale fading


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2-

Log-Normal Shadowing


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3-

Knife-Edge [غى

]


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2-ray proof as in 2013 (i)

The signal nulls at the receiver: (Note 1, Page 14)

Final expressions: (Midterm Exams Solutions by Yahia page 1)


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Midterm Exams Solutions by Yahia pages 5, 6


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Final 2011

Same as 2013 above ↟↟↟↟↟

Final 2010

Same as 2012 © ↟↟↟↟↟↟↟

Final 2009

Same as 2013 (i)

Same as 2014 (i) and 2013 (ii)

Final 2008

i-

Same as 2013 (i)

ii-

Same as 2014 (i) and 2013 (ii)


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2- Spherical earth & Refraction

Final 2014


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و ريينس كرة ب خف رق م ب عت ر نير


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Ch.4: Diversity and Equalization Final 2014

i-

Note 3 from (20 to 23)


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ii-

Note 3 Pages (23 and 25)


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Final 2013

i-

Repeated

ii-

Repeated

Final 2010


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i-

Note 3 from (18 to 20)


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ii-

Repeated

iii-

Repeated

Final 2009

A-

i-

Repeated

ii-

Repeated

B-

i.

Repeated

ii.

Repeated

iii.

Repeated


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Ch.5: Spread Spectrum Techniques

1- Codes

Final 2014

b)زكرة

8قبل يدير

i)


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c) بد يدير00زكرة


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Final 2012

M-sequence ( قبل يدير7زكرة)


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Walsh codes ( قبل ي8زكرة )


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OVSF code ( قبل ي8زكرة )


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Gold code ( قبل ي8زكرة )

Properties and usage: explained in 2014 above ..


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Final 2011

b)زكرة

8قبل ي

i) explained previously in 2012,2014

ii) No of orthogonal codes -MAI- jamming (not sure)

iii) Walsh 64 : in IS-95 CDMA1 , Gold code : UMTS (3g)-GPS-LTE

c) قبل ي7زكرة


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Final 2009

Final 2008

a)

M-sequence: used in CDMA applications

Walsh 64: used in IS-95 CDMA1

Gold code: used in UMTS (3g)- GPS -LTE

OVSF: used in UMTS


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2- DSSS

Solution

i-Note (1) page [6 to 12]


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ii- Note (1) page [16]

Solution

a.i) Note [1] page [6 to 14]

Repeated

iii)


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Solution

ii) Note [1] page [6 to 14]

Repeated

Solution

b) Note [1] page [6 to 14]

The same as the first question + this figure


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c) Note [1] page [18 + 20 + 21 + 22]


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Solution

a) Note [1] page [6 to 14]

Repeated

Solution

A) Note [1] page [6 to 14]

Repeated


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3- FHSS

Final 2014

From 2015 Summary Ch.5


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Final 2013


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Final 2012

Repeated Final 2013 (ii)

Repeated Final 2013, C

Final 2011

Repeated Final 2013 (ii)


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Repeated Final 2012, B

Final 2010

Final 2008



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Ch.7: OFDM/MA Techniques

Final 2014

Final 2013:

Final 2012

Final 2011

Notes 3, page 8 and 9 or Revision of Eng. El Fikey Engybook page 50


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i. Sub-carrier Frequency spacing needed to achieve orthogonality

ii.


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Advantages of CP


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iii.


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Methods to decrease it :

iv. We can’t use OFDM in uplink as a reason of the PAPR, and it’s only

solution to increase the efficiency is to use Class A Amplifiers with ἠ = 25%, so we

will use more power and battery will die (Mobile phone battery)


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Ch.X:


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Final 2011

Note 9 Page 41, 42 in pdf


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Appendix

A) Q-function Table


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B) Radar Probability of Detection Curve

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[Advanced Communication System] Exams Solved