EE160 Fall 2014
Homework # 2
San Jos
e State University
Due: Thu. 9/11/14
1. A constant signal x(t) = c, where c is a real-valued constant, can be interpreted as a
periodic train of rectangular pulses with 100% duty cycle d = T = 1. Using the Fourier
seri
EE160 Fall 2014
Homework # 6
San Jos
e State University
Due: Thu. 10/23/14
1. The message signal into a DSB-SC modulator is m(t) = sinc(10000t). The carrier c(t)
has frequency fc = 100 kHz and amplitude Ac = 2.
(a) Use a computer to sketch the modulated s
EE 160 - Fall 2012
San Jos
e State University
Solution of Midterm Exam # 1
Problem 1 (45 points) The signal x(t) = 2 cos(2fc t), with fc = 1 kHz, is sampled
using a bilateral switch with gating function g(t) a square waveform (i.e., a periodic train
of re
EE160 Fall 2014
Homework # 1
San Jos
e State University
Due: Thu. 9/4/14
1. Find the center frequency fc and bandwidth B of the 915-MHz ISM band in the U.S.A.
(Hint: FCC document in the website.)
2. Consider the low-noise amplifier (LNA) model ZRL-2150+ p
EE160 Fall 2014
Homework # 4
San Jos
e State University
Due: Tue. 9/30/14
1. Consider the bandlimited signal x(t) = sinc (100t).
(a) Determine the minimum Nyquist sampling frequency fs,min .
(b) Sketch carefully the ideal sampled spectrum X (f ) with a gu
EE160 Fall 2014
San Jos
e State University
Solution of Homework # 2
1. For a periodic train of rectangular pulses of amplitude c and duty cycle d = 1, the
Fourier series coefficients (FSC) are given by
(
c, n = 0,
xn = c sinc(n) =
0, n 6= 0.
2. First, the
EE160 Fall 2014
San Jos
e State University
Solution of Homework # 4
1. (a) fs,min = 100 Hz.
(b) A guardband of 50 Hz gives fs = 150 Hz. Sketch:
(c) Practical sampling with 50% duty cycle. Sketch:
2. (a) Transfer function:
1
|f | 50,
150 ,
H(f ) = g(f ),
EE160 Fall 2014
San Jos
e State University
Solution of Homework # 3
1. At input power equal to 0 dBm, the main (fundamental) power is 25 dBm and the IM3
power is 9 dBm. Therefore, THD (dB) = 9 dBm 25 dBm = 16 dBc or 2.5%.
2. For a triangular waveform x(t)
EE160 Fall 2014
San Jos
e State University
Solution of Homework # 1
1. fc = 915 MHz and bandwidth B = 28 MHz.
2. Input-output power characteristic:
!"#$"#%
&'()*%
+,-./%
!"#$%&%'
!"#$%
&!'%
23%
4%,-%
!"#$%&'
!"()*+&,'
:%
549,-792%
500&678%
01$"#%
&'()*%
+
EE160 Fall 2014
Homework # 7
San Jos
e State University
Due: Thu. 10/30/14
1. The FCC defines four types of AM radio stations.
(a) Find the definition of each type of AM radio station.
(b) What type of AM radio station corresponds to a broadcast station?
EE160 Fall 2014
Homework # 3
San Jos
e State University
Due: Thu. 9/18/14
1. Evaluate the THD (dB) of the amplifier in problem 2 of Homework 1 with input power
equal to 0 dBm.
2. Determine the THD of the triangular waveform discussed in class. How does it