HP 8924E, Assembly

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Chapter 1, Introduction
Theory of Operation
N:\mkt\MANUALS\HP8924C\ALR\intro.fb
RF and DUPLEX
Outputs
The Input assembly receives the signal from the output assembly and routes it to
the selected output port: RF IN/OUT or DUPLEX OUT. The signal first goes to a
variable attenuator for level control. If the DUPLEX OUT port is selected, the
signal then goes directly to that port without additional attenuation. If the RF IN/
OUT port is used as an output, the signal passes through additional attenuation
before reaching the port. This is why a greater signal level can be output through
the DUPLEX OUT port than through the RF IN/OUT port.
Figure 5 RF Generation Path Overview
Signal Generator Synthesizer (A24)
1 MHz from
Reference
Assembly
div/n
FM Mod. from
Mod. Dist.
Spec. Analyzer
Sweep
500-1000 MHz
IQ Modulator Assembly (A25)
I/Q Modulator
Cell Site
Cell Site
Analog (A8)
Digital 1
Cell Site
Digital 2
Protocol
Processor
AWGN (Noise) from
CDMA Reference
4 channels of
I&Q data
1 channel of
I&Q data
ADC &
Summing
Output Assembly (A26)
500-1000 MHz
500-1000 MHz
div/2
250-500 MHz
1 GHz from Reference Assembly
250 kHz-250 MHz
Amplitude
Modulator
RF
Amp
Automatic
Level Control
AM from Mod.
Distribution Assembly.
RF Amplitude
Adjust from
Host Controller
Input Assembly (A5)
Variable
Attenuator
DUPLEX
RF IN/OUT
To the Receiver
Assembly
OUT
(A6)
(A9)
(A7)