Ceyear 4041 Series, User Manual

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Chapter X Working Principle
132
Chapter X Working Principle
Spectrum analyzer 4041 includes the products working on 9 kHz ~ 20 GHz, 9 kHz ~ 26.5 GHz, 9 kHz ~ 32 GHz,
and 9 kHz ~ 44 GHz, with the spectrum measurement and analysis, field strength measurement, occupied
bandwidth, channel power, adjacent channel power, audio demodulation, IQ data capture and other measurement
functions, and provides the Interference Analyzer, AM/FM/PM analyzer of analog modulation signal, USB Power
meter and other options. RF signal frequency, amplitude and other parameters may be measured. Functional block
diagram of spectrum analyzer 4041 is as shown in Fig 10-1.
Fig10-1 Block diagram of instrument functions
System hardware mainly comprises of the microwave and millimeter wave frequency conversion module,
frequency synthesizer board, IF channel plate, CPU board, display, keyboard, tracking generator (option), etc.
Of which, microwave and millimeter wave frequency conversion module includes the 60 dB program-controlled
step attenuator as well as the switching filter and frequency conversion. The attenuation value of the automatic
program-controlled step attenuator may be set by the whole machine according to the reference level or by the
user manually to provide the suitable mixer level. Switching filter and frequency conversion complete the
sub-band filtering and frequency conversion processing of RF input signal, and output the IF signal to the IF
channel plate.
IF channel plate filters the IF signal from the frequency conversion module, performs the gain control for different
bands to adjust the amplitude value of AD sampling signal, and finally outputs the differential digital signal to
External
trigger
input
IF output
CPU board
Keyboard
ARM
core
module
FPGA/
CPLD
Power conversion
and management
Interface
and
display
driver
LCD
Touch
screen
Power
sensor
GPS
Frequency synthesizer
board
Microwave and millimeter wave
frequency conversion module
IF A/D
Gain control
and filtering
Intermediate frequency
channel plate
Switching filter and
frequency conversion
Programmable
attenuator
10MHz reference
Input/output
RF input
Local oscillation
generation
Reference ring
AC
power
Tracking generator board
(option)
RF output