Chapter 2
83
Block Diagrams
A7 Baseband I/Q Assembly (Option B7C)
A7 Baseband I/Q Assembly (Option B7C)
The A7 assembly processes I and Q baseband signals to facilitate
analyzer measurement of I and Q signals, both independently and
together. The baseband I/Q assembly performs the following functions:
• provides selectable load impedances of 50
Ω
, 600
Ω
, and 1M
Ω
• provides input voltage protection
• provides balanced and unbalanced input options
• performs both digital and analog calibration of the baseband signals
• performs analog to digital conversion
• prepares the input signals for further processing by the CPU
I/Q Input Circuitry
The external I, I, Q, and Q connectors allow input of balanced and
unbalanced signals. Input impedances of 50
Ω, 600Ω,
and 1 M
Ω
can be
selected through the front panel. The 50
Ω
and1 M
Ω
can be used for
unbalanced inputs, while the 600
Ω
and 1 M
Ω
impedance setting can be
used for balanced inputs. Protection is provided against excessive ESD
transient and DC input voltages using varister clamps.
Input Amplifiers
The first of three input amplifiers allows for high impedance, positive
and negative inputs signals, while the second and third amplifiers
convert differential signal inputs to single-ended signals.
ADC
The ADC converts the analog I and Q signals to digital and has a
resolution of 14 bits.
Digital Signal Processing Block (DSP)
The DSP block consists of a deserializer, a MUX, and a custom ASIC
chip that performs essential signal processing tasks, such as filtering
and decimation. The deserializer converts the serial output of the ADC,
whether an I, Q, or I/Q signal, to multiple lines that feed into the MUX.
The MUX distributes the signals to the ASIC chip.
Summary of Contents for E4406A VSA Series
Page 4: ...4 ...
Page 10: ...10 Contents ...
Page 11: ...11 1 Troubleshooting ...
Page 66: ...66 Chapter1 Troubleshooting How to Return Your Instrument for Service ...
Page 67: ...67 2 Block Diagrams ...
Page 119: ...Chapter 2 119 Block Diagrams Block Diagrams Block Diagrams ...
Page 120: ...120 Chapter2 Block Diagrams Block Diagrams ...
Page 122: ...122 Chapter2 Block Diagrams Block Diagrams ...
Page 124: ...124 Chapter2 Block Diagrams Block Diagrams ...
Page 125: ...125 3 Parts List ...
Page 164: ...164 Chapter3 Parts List Hardware ...
Page 165: ...165 4 Assembly Replacement ...
Page 169: ......
Page 170: ...170 Chapter4 Assembly Replacement Removal and Replacement Procedures ...
Page 227: ...Chapter 4 227 Assembly Replacement Front Frame Subassemblies Figure 4 39 Keypad Parts ...
Page 231: ...231 5 Post Repair Procedures ...
Page 262: ...262 Chapter5 Post Repair Procedures Automated Adjustments ...