... possible spurious frequen-
cies due to the two RF frequencies:
f
RF1
¼
nf
LO
À f
IF
m
ð5:29Þ
f
RF2
¼
nf
LO
þ f
IF
m
ð5:30Þ
The RF frequencies of f
RF1
and f
RF2
will generate spurious responses.
5.8 ... generated.
Any RF frequency that satisfies the following equation can generate spurious
responses in a mixer:
mf
RF
À nf
LO
¼Æf
IF
ð5:28Þ
where f
IF
is the desired IF frequency....
... wireless
communications are frequency division multiple access (FDMA), time division
multiple access (TDMA), and code division multiple access (CDMA). Frequency
division multiple access and TDMA are ... frequency band, and interference caused by intermodulation and sideband
distortion.
10.3 TIME DIVISION MULTIPLE ACCESS AND TIME DIVISION
MULTIPLEXING
A TDMA or time division multiplexing (TDM)...
... various
services such as voice mail, email, video, messaging, data, and computer on-line
services. The direct link between satellites and personal communication systems can
provide voice, video, ... to cable television, and the end of the Cold War has made many military
technologies available to civilian applications. The global positioning systems
(GPSs), RF identi®cation (RFID) systems, ....
... axis.
The Smith chart can be used to ®nd (1) G
L
from Z
L
and vice-versa; (2)
Z
in
from
Z
L
and vice-versa; (3) Z from Y and vice-versa; (4) the VSWR; and (5) d
min
and
d
max
. The Smith ... normalized values.
2. Moving away from the load (i.e., toward the generator) corresponds to
moving in a clockwise direction.
3. A complete revolution around the chart is made by moving a distance
l .....
... relevant performances and
design parameters will be given for introductory purposes.
An antenna is a component that radiates and receives the RF or microwave power.
It is a reciprocal device, and ... is a reciprocal device, and the same antenna can serve as a receiving or
transmitting device. Antennas are structures that provide transitions between
guided and free-space waves. Guided waves...
... capacitances. Active filters can be built
by using active devices such as MESFETs in microwave frequencies and CMOS in
RF. The active devices provide negative resistance and compensate for the losses ... ATTENUATORS
135
The first two terms will give
i ¼ a
1
A cos o
RF
t þ a
2
A
2
cos
2
o
RF
t
¼ a
1
A cos o
RF
t þ
1
2
a
2
A
2
þ
1
2
a
2
A
2
cos 2o
RF
t ð4:16Þ
A DC current appears at the...
... device impedance is a function of frequency ð f Þ, bias
current ðI
0
Þ, generated RF current ðI
RF
Þ, and temperature ðTÞ. Therefore, at the
resonant frequency, we have
Im½Z
D
ð f ; I
0
; I
RF
; ... for space or battery operating systems.
The DC-to -RF conversion efficiency is given by
Z ¼
P
RF
P
DC
 100% ð6:4Þ
where P
RF
is the generated RF power and P
DC
is the DC bias power. I...
... receiving. A duplexer
is used to separate the transmitting and receiving signals. A circulator is shown in
Fig. 7.2 as a duplexer. A switch can also be used, since transmitting and receiving ... radar provides the target coordinates for the tracking
radar. The tracking radar acquires the target by performing a limited search in the
area of the designated target coordinates provided by ... f
d...
... À1dB
Space loss
dB
Atmospheric loss À2dB
Polarization loss À1dB
Receiving feed loss À2dB
Receiving antenna gain 35 dB
Receiving antenna pointing error
þÞ À1dB
REFERENCES
1. E. A. Wolff and R. ... picture of this vision [8]. The
WLAN is for wireless indoor radio communication services or high-data-rate
communications. The system employs a central microcell hub (base station) that
services cord...
... of modulation is always needed in an RF system to translate a
baseband signal (e.g., audio, video, data) from its original frequency bandwidth to a
specified RF frequency spectrum. Some simple modulation ... without their interfering with
each other. One example is that many users can use the same long-distance
telephone line simultaneously without creating a jumbled mess or interference....