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AWR Visual System Simulator Modeling Guide

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Table of Contents

1. Simulation Basics
1.1. Additional Documentation
1.2. Typographical Conventions
1.3. Basic Concepts
1.3.1. RF Budget Analysis and RF Inspector Simulations
1.3.2. Time Domain Simulations
1.3.3. Sweeping Simulations
Design Parameters
Controlling Sweeps
Swept Measurements
1.4. Data Signals
1.4.1. Digital Signals
1.4.2. Analog Signals
1.4.3. Complex Envelope Signals
Working with Complex Envelope Signals
Center Frequency Of Zero
Other Benefits and Limitations
RF Budget Analysis Simulations
1.4.4. Sampling Frequencies, Data Rates and Oversampling
Sampling Theory and Aliasing
Selecting A Sampling Frequency
Signal Bandwidth
1.4.5. Generic Signals
1.4.6. Fixed-Point Signals
1.4.7. Signal Properties
1.4.8. Primary Data Path
1.5. Automatic Configuration
1.6. Spectral Analysis in Time Domain Simulations
1.6.1. Fourier Transforms
1.6.2. Averaging, Windowing and Power Spectrum Estimation
1.6.3. Frequency Resolution and Video Bandwidth
1.6.4. Negative Complex Envelope Frequencies
1.6.5. Measuring Channel Power
1.7. AWR Microwave Office Schematics: Parameterized Subcircuits and Sweeping
1.7.1. Passing Parameters from AWR Microwave Office Circuits
1.7.2. Using a AWR Microwave Office Circuit Swept Parameter in a System Diagram
1.8. References
2. RF Modeling in AWR VSS
2.1. RF Blocks In AWR VSS
2.1.1. Linear Filters
2.1.2. Amplifiers
2.1.3. Mixers
2.1.4. Miscellaneous Blocks
2.1.5. Working with Non-RF Blocks
2.2. RF Budget Analysis
2.2.1. Simulation Frequencies
2.2.2. Computed Values
2.2.3. Measurement Output
2.2.4. Nonlinear Modeling
Saturation Effects
S12 Limitations
2.2.5. Thermal Noise Modeling
2.2.6. Phase Noise Modeling
2.2.7. Additional Information
2.3. RF Inspector
2.3.1. Indicating IM Products
2.3.2. RF Inspector Dialog Box
Details Section
Heritage Window
Signal Classification
Other Features
2.3.3. Modulated Signals
CW and Modulated Signal Display
2.3.4. Performance Considerations
Frequency Settings
Noise Floor
Component Limits
Simulation Convergence
2.3.5. How RFI Works
2.3.6. Feedback Loops in RFI
2.3.7. Additional Notes
Saturation Effects
S12 Limitations
Additional Hints and Tips
2.4. Bi-directional RF Blocks
2.5. Impedance Mismatch Modeling
2.5.1. VSWR Parameters
2.5.2. Block Support for Impedance Mismatch Modeling
2.5.3. Time Domain Modeling Basics
Determining Impedances
Voltage Corrections
2.5.4. Source and Load Impedances
2.5.5. Interfacing to Non-RF Blocks
2.5.6. Additional Notes
Feedback Loops
2.6. Temperature Dependent Parameters of RF Blocks
2.6.1. RF Blocks that Support Temperature Dependence
2.6.2. Piecewise Interpolation Support
2.6.3. Frequency Dependency Support
2.7. Time Domain Filter Considerations
2.7.1. FIR Filters
Frequency Sampling
Windowed FIR Filters
Windowed FIR + Allpass IIR Filter
Other FIR Design Techniques
2.7.2. IIR Filters
2.7.3. Working With Circuit Filter Based Blocks
2.8. Time Domain Nonlinear Modeling Issues
2.8.1. Aliasing
2.8.2. Saturation Effects
2.9. NI Technical Data Management Streaming (TDMS) File Format
2.9.1. Analog Waveforms
2.9.2. Digital Waveforms
3. Noise Modeling in AWR VSS
3.1. Modeling Noise in AWR VSS
3.2. Circuit Noise
3.2.1. Linear RF Blocks
3.2.2. Amplifiers
3.2.3. Mixers
3.2.4. Additional Notes
Combining Signals with Ambient Noise
3.3. Channel Noise
3.4. Phase Noise
3.4.1. Phase Noise in RF Budget Analysis
3.4.2. Phase Noise in Time Domain Simulations
Generating Phase Noise
Measuring Phase Noise
3.5. SNR, Eb/N0 and Es/N0
3.5.1. SNR
3.5.2. Eb/N0 and Es/N0
3.6. Measurement Noise Floor
3.7. Noise and Negative Frequency Folding
3.8. RF Budget Analysis Noise Notes
3.8.1. Operating Point and Noise Simulations
3.8.2. Spot Noise Simulations
3.8.3. Noise Frequency Ranges
Utilizing Spot Noise Simulations
Specifying Frequency Offsets
Noise Sample Points
4. AWR VSS Modeling Hints and Tips
4.1. RF Budget Analysis Simulations
4.1.1. Signal Simulations
4.1.2. Block Simulations
4.1.3. Phase Noise Simulations
4.1.4. Thermal Noise Simulations
4.1.5. RF Budget Analysis Paths
4.2. RF Inspector Simulations
4.3. Differences Between RF Budget Analysis and RF Inspector Simulations
4.4. Time Domain Simulations
4.5. Phased Arrays and MIMO Arrays
4.5.2. Building from Blocks
4.5.3. Additional Phased Array/MIMO Antenna Array Tips
4.6. Miscellaneous

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