Intersystem EMC Analysis, Interference, and Solutions

1 Definitions
1.1 Introduction
1.2 Objectives
1.3 Interference
1.4 Radio Frequency Interference
1.5 Compatibility
1.6 EMC and RF Compatib
1.7 Emissions and Susceptibility
1.8 The System
1.8.1 Definition
1.8.2 System Content
1.9 External Systems
1.9.1 External System Types
1.9.2 Definition
1.10 Intrasystem and Intersystem Compatibility
1.11 Interference to and from the System
1.12 One-Way and Two-Way EMC
1.13 Electromagnetic Environment
1.14 Signal Types
1.15 Hierarchy
1.16 Device Level
1.17 Platform Level
1.18 Site Level
1.19 Arena Level

2 EMC Requirements
2.1 Objective
2.2 Device Level EMC Requirements
2.2.1 Objective
2.2.2 The Device EMC Requirement
2.2.3 Capability to Comply with the Operational Requirements
2.2.4 Definition Approaches
2.3 EMC Requirements Within and Between Platforms
2.3.1 EMC Within and Between Platforms
2.3.2 Distance Between Platforms
2.3.3 Near-Field and Far-Field
2.4 EMC Requirements at the Platform Level
2.4.1 The Platform EMC Requirement
2.4.2 Capability to Comply with the Operational Requirement
2.4.3 Inter- and Intra-EMC
2.5 EMC Requirements at the Site L
2.5.1 The Site EMC Requirement
2.5.2 Inter- and Intra-EMC
2.6 EMC Requirements at the Arena Level
2.6.1 The Arena EMC Requirement
2.6.2 The Near-Far Requirement
2.6.3 Inter- and Intra-EMC
2.7 System EMC Requirements
2.8 Requirements Sum
2.9 Relationship to MIL-STD
2.10 Maximum Allowed Interference Level
2.11 The Performance Criteria
2.12 The Affecting Parameter
2.13 Gradual Performance Degradation
2.14 Interference Threshold
2.15 Crash Threshold
2.16 Performance Degradation Region
2.17 Interference Probability Threshold
2.18 Operational Damage Level
2.18.1 Nuisances
2.18.2 Mission Effectiveness Decreases
2.18.3 Mission Failur
2.18.4 Safety Risks

3 EMC Analysis and Survey
3.1 EMC Survey Objectives
3.2 Included in the Survey
3.3 Required Survey Outcom
3.4 The Need for Handling EMC Problems
3.5 The S/I Approach
3.6 The DES Approach
3.7 The Participants in the Interfering Mechanism
3.7.1 The Interfering Transmitter
3.7.2 The Interfering Medium
3.7.3 The Interfered Receiver
3.7.4 The Desired Transmitter
3.7.5 The Desired Medium
3.8 Worst-Case and Least-Worst-Case
3.8.1 The Worst-Case Dilemma
3.8.2 Least-Worst or Easiest Case
3.8.3 Saving Calculation Time
3.8.4 Worst-Case Parameters
3.9 A Possible Structure for the EMC Survey Report
3.9.1 Executive Summary
3.9.2 General
3.9.3 Methodology
3.9.4 Systems in the Analysis
3.9.5 Device Data
3.9.6 Scenarios
3.9.7 Requirements
3.9.8 Results
3.9.9 Summary and Recommendations
3.9.10 Annexes

4 Interference Types
4.1 Interference Types Criteria
4.2 Interfering Device Types
4.3 Antenna Lobe Types
4.4 Interference Outcome Types
4.4.1 Interference—the Desired Signal Is Not Received
4.4.2 Sensitivity Degradation by X dB
4.4.3 DES
4.4.4 False Reception
4.4.5 Damage
4.4.6 Degradation of Digital Communication
4.5 Interference Bandwidth Types
4.5.1 Narrowband Interference
4.5.2 Broadband Interference
4.5.3 Full-band Interference
4.6 False Reception
4.7 Interference Types According to Their Source
4.7.1 Interference from Transmitter and Receiver Parameters
4.7.2 Interference from Transmitter Parameters
4.7.3 Interference from Receiver Parameters

5 Interference fromBoth Transmitter and Receiver
5.1 Transmitter Spectrum
5.1.1 Transmitter Spectrum Definition
5.1.2 Source of the Interference Phenomenon
5.1.3 Calculating FDR
5.1.4 The Interference Effects
5.1.5 Calculating the Received Interference Level
5.2 CCI
5.2.1 Definition
5.2.2 Source of the Phenomenon, Nonintentional Case
5.2.3 Source of the Phenomenon, Intentional Case
5.2.4 The Interference Effects
5.2.5 Calculating the Received Interference Level
5.2.6 The BWF in CCI
5.3 ACI
5.4 Splitting the FDF

6 Interference from the Transmitter
6.1 Transmitter Frequency Bands
6.1.1 Transmission Band
6.1.2 Adjacent Channels or Modulation Band
6.1.3 In-Band
6.1.4 Out-of-Band
6.2 Interference from the Transmitter Spectrum—ACI
6.2.1 The Interference Effects
6.2.2 Calculating the Received Interference Level
6.2.3 Additional Definitions of the Parameter
6.2.4 Default Value for Modulated Signals
6.2.5 Default Value for Pulsed Signals
6.3 Interference from Spurious Emission—SPR
6.3.1 Source of the Interference Phenomenon
6.3.2 Definition of the Parameter
6.3.3 The Interference Effects
6.3.4 Calculating the Received Interference Level
6.4 Interference from PHN
6.4.1 Source of the Interference Phenomenon
6.4.2 Definition of the Parameter
6.4.3 The Interference Effects
6.4.4 Calculating the Received Interference Level
6.5 Interference from BBN
6.5.1 Source of the Interference Phenomenon
6.5.2 Definition of the Parameter
6.5.3 Measuring BBN
6.5.4 Default Value
6.5.5 The Interference Effects
6.5.6 Interference Relevance
6.5.7 Calculating the Received Interference Level
6.6 Interference from HAR
6.6.1 Source of the Interference Phenomenon
6.6.2 Definition of the Parameter
6.6.3 Default Value
6.6.4 The Interference Effects
6.6.5 Checking the Harmonics Content Feasibility
6.6.6 Calculating the Received Interference Level
6.6.7 The BWF for Harmonic Interference
6.6.8 Calculating the Interference Close to Harmonics
6.7 Interference from the TIM
6.7.1 Source of the Interference Phenomenon
6.7.2 Definition of the Parameter
6.7.3 Default Value
6.7.4 The Interference Effects
6.7.5 Calculating the Received Interference Level
6.7.6 Checking Intermodulation Feasibility
6.8 Interference from LFM Radar
6.8.1 Slow Sweep
6.8.2 Fast Sweep

7 Interference from the Receiver
7.1 Receiver Frequency Bands
7.1.1 Reception Band
7.1.2 Selectivity Band
7.1.3 In-Band
7.1.4 OOB
7.2 Required (S/I )r
7.2.1 Source of the Interference Phenomenon
7.2.2 Definition of the Parameter
7.2.3 Measuring (S/I)r
7.2.4 Default Value
7.2.5 (S/I)r and Processing Gain
7.2.6 Protection Ratio
7.2.7 Jamming Ratio
7.3 General Aspects in Receiver Interference
7.3.1 Direct and Indirect Definition of the Interference Parameter
7.3.2 Interference Effects
7.3.3 Equivalent Interfering Signal Level
7.4 Interference from SEL
7.4.1 Source of the Interference Phenomenon
7.4.2 Definition of the Parameter
7.4.3 Measuring LSEL and the Indirect Definition
7.4.4 Indirect Definition of the Parameter
7.4.5 Calculating the Received Interference
7.4.6 The BWF
7.5 SAT and Desensitization
7.5.1 Amplifier Compression
7.5.2 The Interference Effect
7.5.3 Definition of the Parameter
7.5.4 Acquiring the –1-dB Compression Point
7.5.5 Comparing Interference and SAT
7.5.6 Calculating the Received Interference Level
7.6 DMG
7.6.1 Source of the Interference Phenomenon
7.6.2 Definition of the Parameter
7.6.3 Acquiring the DMG Level
7.6.4 Default Value
7.6.5 Calculating the Received Interference Level
7.7 Interference from IMR
7.7.1 Source of the Interference Phenomenon
7.7.2 Definition of the Parameter
7.7.3 Measuring the IMR
7.7.4 Calculating the Received Interference Level
7.8 Interference at the IF
7.8.1 Source of the Interference Phenomenon
7.8.2 Definition of the Parameter
7.8.3 Calculating the Received Interference Level
7.9 Interference from LO Radiation
7.9.1 Source of the Interference Phenomenon
7.9.2 Definition of the Parameter
7.9.3 Calculating the Received Interference Level
7.10 Interference from RIM
7.10.1 Source of the Interference Phenomenon
7.10.2 Definition of the Parameter
7.10.3 Measuring the Parameter
7.10.4 Default Value
7.10.5 Calculating the Intermodulation Level
7.10.6 Calculating the Intercept Point
7.10.7 Calculating the Received Interference Level
7.10.8 Checking the Intermodulation Feasibility
7.11 Harmonics and Intermodulation
7.11.1 Harmonics
7.11.2 Introduction to Intermodulation
7.11.3 The Slope of the Intermodulation
7.11.4 The Intercept Point Concept
7.11.5 The Intermodulation Spectrum
7.11.6 The Third- and nth-Order Intermodulation Equations
7.11.7 Intermodulation from Nonequal Signals
7.11.8 Intermodulation from Multiple Transmitters
7.11.9 Number of Intermodulation Products
7.12 In-Band and OOB Interference

8 Calculating the Received Interference Level
8.1 The Calculation Principle
8.2 Calculating the Received Interference Level
8.2.1 Transmitter Pow
8.2.2 Interference Level Relative to CCI
8.2.3 Transmitter External Filter
8.2.4 Transmitter Cable Loss
8.2.5 Transmitter Waveguide Loss
8.2.6 Transmitting Antenna Gain
8.2.7 Transmitting Antenna Side Lobes
8.2.8 Path Loss and Coupling
8.2.9 Polarization Loss
8.2.10 Receiving Antenna Gain
8.2.11 Receiving Antenna Sidelobes
8.2.12 Receiver Cable Loss
8.2.13 Receiver Waveguide Loss
8.2.14 Receiver External Filter
8.2.15 BWF
8.3 Power Sum of Multiple Interferers

9 Interference Margin and Its Meaning
9.1 Background
9.2 IMRG in the S/I approach
9.2.1 The Criterion
9.2.2 Procedure and Steps of IMRG Calculation
9.2.3 Desired Signal Level S Calculation
9.2.4 Interference Threshold Calculation
9.2.5 Interference Level I Calculation
9.2.6 Interference Plus Noise Calculation
9.2.7 IMRG Calculation
9.2.8 Relationship Between IMRG and Fade Margin
9.3 IMRG in the DES Approach
9.3.1 The Criterion
9.3.2 DES Calculation
9.3.3 DES versus I/N
9.3.4 Choosing the Interference Threshold
9.3.5 Procedure and Calculation Steps
9.3.6 Interference Threshold Calculation
9.3.7 IMRG Calculation
9.3.8 DES versus I
9.3.9 IMRG Impact on DES
9.4 IMRG Impact on the Range
9.4.1 Background
9.4.2 Range Degradation in the S/I Approach
9.4.3 Range Degradation in the DES Approach
9.5 Interference to Short Desired Paths
9.6 Applying the DES Approach for Interference to Radar
9.7 FM Degradation
9.8 Inverse Calculation Technique
9.9 Sensitivity Level as Wrong Threshold Level
9.10 EMC Calculation Summary

10 The Interference Range and the Reception Range
10.1 Hierarchy Level and Interference Types
10.2 Calculating the Interference Range
10.2.1 The Problem
10.2.2 Interference Range without Terrain Influence
10.2.3 Interference with Terrain Influence
10.3 Calculating the Reception Range with Interference
10.3.1 Background
10.3.2 Signal-to-Interference Plus Noise Ratio
10.3.3 Reception Range without Terrain
10.3.4 Reception Area with Terrain
Reference

11 Propagation Models for EMC
11.1 Difference Between Communication and EMC Models
11.2 Models without Terrain Influence
11.3 Models Based on DTM
11.4 Generic Terrain-Influenced Model Path-Loss Model
References

12 Coupling Between Antennas
12.1 Measurement
12.2 Scaling
12.3 Prediction by Simulation
12.4 Approximate Free-Space Calculation
12.5 Frequency Dependency

13 Relative Angles Between Antennas
13.1 The Problem
13.2 Transformation by Rotation
13.3 Calculating θ and ϕ

14 Antenna Gain in Intercardinal Angles
14.1 The Problem
14.2 The Guiding Principle
14.3 Coordinate Systems
14.4 Coordinates System Transformation
14.5 Symmetrical Antenna Pattern
14.6 The Sum in Decibels Method in the Symmetrical Case
14.7 Nonsymmetrical Antenna Pattern
14.8 The Sum in Decibels Method in the Nonsymmetrical Case
14.9 BWAZ > BWEL
14.10 BWEL > BWAZ
14.11 Reducing the Estimation Error
14.12 Real versus Envelope Pattern
14.13 Verification by Simulation
14.14 Examples
14.15 Summary

15 Near-Field
15.1 Far-Field Definition
15.2 Near-Field Definition
15.3 Near-Field Distanc
15.4 Very Small Antenna Near-Field Distance
15.5 Aperture Antenna Near-Field Distance
15.6 Wire Antenna Near-Field Distance
15.7 Near-Field Distance Between Two Antennas
15.8 Near-Field Path Loss
15.9 Near-Field Path Loss for Aperture Antennas
15.9.1 Main Lobe
15.9.2 Main Lobe Calculation Steps
15.9.3 Sidelobes’ Path Loss

16 Interference Probability
16.1 Background
16.2 Accumulated Probability from Multiple Phenomena
16.3 Accumulated Probability from Multiple Interferers

17 Interference Probability—Antenna Patterns Aspect
17.1 The Problem
17.2 Main Lobe versus Sidelobes Case
17.3 Antenna Pattern versus Fixed Antenna Case
17.4 Two Rotating Antennas Case
17.4.1 Step 1: Calculating the Antennas’ Probability Density Function
17.4.2 Step 2: Calculating the Viewing Sector
17.4.3 Step 3: The Probability of a Certain Antenna Pattern Value
17.4.4 Step 4: The Joint Probability Density Function
17.4.5 Step 5: Reference Interference Margin in the Main Lobe
17.4.6 Step 6: Interference Margin of the Event i,j
17.4.7 Step 7: Interference Probability of the Event i,j
17.4.8 Step 8: Interference Probability
17.4.9 Step 9: Interference Probability from the Range Gate A
17.4.10 Example

18 Probability of Frequency Difference
18.1 The Problem
18.2 Mathematical Background
18.3 The General Case
18.4 Continuous Frequency Allocation
18.5 Case 1: Identical Frequency Bands
18.6 Case 2: Nonoverlapping Frequency Bands
18.7 Case 3: Partially Overlapping Frequency Bands
18.8 Case 4: One Frequency Band Is Included in the Other
18.9 Fixed-Frequency and Frequency-Hopping Device
18.9.1 Fixed-Frequency Devices
18.9.2 Frequency-Hopping Devices

19 Probability of Pulse Interference
19.1 The Problem
19.2 Definitions
19.3 Calculating RMin
19.4 Calculating RMax
19.5 Calculating the RMin Probability
19.6 Calculating the RMax Probability
19.7 Summary of Interference Probability
19.8 Various Cases
19.8.1 Probabilities Reach the Extreme Zero and One Values Case
19.8.2 Probabilities Do Not Reach the Extreme Zero and One Values Case
19.8.3 a >> d Case
19.8.4 d >> a Case
19.8.5 Identical Pulse Width Case
19.8.6 Whole Number of Interfering Pulses Case
19.8.7 Additional Probability Graph Shapes
19.9 Radar Pulses Interference

20 Pulse Interference to Digital Communication
20.1 Hierarchy from Bits to Message
20.2 Group Error Rate
20.3 Symbol Error Rate
20.4 Frame Error Rate
20.5 Message Error Rate
20.6 Error Rates with Interferen
20.6.1 General Case
20.6.2 Case 1: PW > tMessage
20.6.3 Case 2: tFrame < PW < tMessage
20.6.4 Case 3: tSymbol < PW < tFrame
20.7 Group Delivery Probability
20.8 Required Number of Retransmissions

21 EMC Between Synchronous Hopping Devices
21.1 Background
21.2 Frequency-Hopping Times
21.3 Synchronous and Orthogonal Devices
21.4 Overlapping
21.5 Distances and Reception Delay
21.6 Solution and Objective
21.7 The Overlapping Portion
21.8 Conditions for Overlapping Interference

22 EMC Solutions
22.1 Background
22.2 Time-Axis Solutions
22.3 Distance-Axis Solutions
22.4 Angle-Axis Solutions
22.5 Frequency-Axis Solutions
22.6 Required Frequency Separation
22.7 Combined Distance and Frequency Separation
22.8 Changing the Specifications

23 EMC Tests
23.1 The Need
23.2 Objectives
23.2.1 Technical EMC Test Objectives
23.2.2 Operational EMC Test Objectives
23.3 IMRG Test Procedure in the DES Approach
23.3.1 Test Block Diagram
23.3.2 Deployment Instruction
23.3.3 Preliminary Tests
23.3.4 Interference Test Procedure
23.3.5 Solution and Repeated Test
23.3.6 Miscellaneous
23.4 IMRG Test Procedure in the S/I Approach
23.4.1 Test Block Diagram
23.4.2 Deployment Instruction
23.4.3 Preliminary Tests
23.4.4 Interference Test Procedure—First Method
23.4.5 Interference Test Procedure—Second Method
23.4.6 Solution and Repeated Test
23.4.7 Miscellaneous
23.5 Differences Between Anticipated and Tested Interference
23.5.1 Case 1: No, No
23.5.2 Case 2: No, Yes
23.5.3 Case 3: Yes, N
23.5.4 Case 4: Yes, Yes
Appendix Device EMC Specifications Table