User's Manual

Canam Technology, Inc. (CTI)
MARK-IV CHANNELIZED (Class A Narrowband) SIGNAL BOOSTER WITH AUTOMATIC
OUTPUT LEVEL CONTROL M4-ChOLC
User’s Operations and Maintenance Manual (O&M)
C.3 INPUT (Rx) INTERMODULATION REJECTION
The M4-ChOLC delivers an
outstanding Input (Rx)
Intermodulation Rejection, which
combined with its Input Sensitivity
of -100 dBm allows the module to
tolerate strong undesired input
carriers of up to -30 dBm with no
interference on the desired
channel, as per TIA standards.
Figure 3 illustrates this case’s input
spectrum.
This is particularly important for
critical applications where the
frequency plan contains channels
that would create 3
rd
and 5
th
order
Intermodulation Products landing
in-band right on other desired
system channel(s), since two or more
very strong signals at F
1
and F
2
frequencies impacting the M4-
ChOLC’s front-end would cause
interference on the desired F
0
channel.
C.4 THE CHANNEL PROCESSOR
The architecture of the M4-ChOLC is based on down&up heterodyne frequency converters,
featuring narrowband Intermediate Frequency (IF) filters and Automatic Gain Control signal
conditioner.
The output signal reproduces the exact input’s frequency and modulation (analog or
digital), as received at the module’s input.
The next diagram in Figure 4 shows the simplified M4-ChOLC architecture.
Figure 3: Input (Rx) Intermodulation Rejection 3
rd
ORDER on-channel IM interference 2*F
1
± F
2
= F
0
0
Level
dBm
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
OTHER NEAR-BY
USERS STRONG
SIGNALS NOT
INTENDED FOR
THIS MODULE
FREQ
MHz
f
0
f
1
f
2
ON-CHANNEL
UNDESIRED
Interference
2*f
1
+/- f
2
= f
o
DESIRED
SIGNAL
MARK-IV CHANNELIZED Signal Booster module (M4-ChOLC) O&M Manual Page 7 of 20