SPRACP3D November   2019  – August 2026 AWR6843 , AWR6843AOP , IWR1443 , IWR1642 , IWR6443 , IWR6843 , IWR6843AOP

 

  1.   1
  2.   Trademarks
  3. 1Introduction
  4. 2Typical Certification Procedure
  5. 3Regulatory Compliance Overview
    1. 3.1 European Union Regulations: Radio Equipment Directive (RED)
      1. 3.1.1 Short Range Radar (EN 305 550)
      2. 3.1.2 Short Range Level Probing Radar (EN 302 729)
        1. 3.1.2.1 Permitted Frequency Ranges and Operating Bandwidth
        2. 3.1.2.2 Antenna Requirements
      3. 3.1.3 RF Exposure Limit - EN 62311
      4. 3.1.4 Electrical Safety - EN 62368
      5. 3.1.5 Electromagnetic Compatibility (EMC) - EN 301 489
    2. 3.2 Federal Communications Commission (FCC)
      1. 3.2.1 End Equipment and FCC Clause
      2. 3.2.2 60GHz Radar Operation (47 CFR § 15.255)
        1. 3.2.2.1 Fundamental Emission Levels, BWs, and Max Duty Cycle
        2. 3.2.2.2 Spurious Emissions
        3. 3.2.2.3 Frequency Stability
        4. 3.2.2.4 FCC Waiver and Other Relevant Information
      3. 3.2.3 Level Probing Radar (47 CFR § 15.256)
        1. 3.2.3.1 Usage Limitations
        2. 3.2.3.2 Fundamental Emissions, BWs
        3. 3.2.3.3 Antenna Restrictions
        4. 3.2.3.4 Unwanted Emissions
      4. 3.2.4 Modular Approval (47 CFR § 15.212)
      5. 3.2.5 Radiation Exposure Requirement
    3. 3.3 Japan Radio Law
      1. 3.3.1 BW, Designated Frequency, and Tolerances
      2. 3.3.2 Out of Band and Spurious Emissions
      3. 3.3.3 Controller Functions
    4. 3.4 Wireless Planning and Coordination Wing (WPC)
      1. 3.4.1 Permitted Frequency of Operations and Approval
      2. 3.4.2 Equipment Type Authorization
    5. 3.5 Federal Telecommunications Institute (IFT)
      1. 3.5.1 Fundamental Emission Levels and BWs
    6. 3.6 National Telecommunications Agency (ANATEL)
      1. 3.6.1 Fundamental Emissions Levels, BWs, and Max Duty Cycle
      2. 3.6.2 Licenses
    7. 3.7 Ministry of Transport and Communications (MTC)
    8. 3.8 National Communications Entity (ENACOM)
  6. 4Applicable Terms and Equations
    1. 4.1 Duty Cycle Factor
    2. 4.2 Effective Isotropic Radiated Power (EIRP)
    3. 4.3 Friis Equation
    4. 4.4 Far-Field Boundary
  7. 5Tools and Setup
    1. 5.1 Hardware Setup
    2. 5.2 Internal Laboratory Test Setup
      1. 5.2.1 Near-Field Circuit Probing
      2. 5.2.2 Occupied Bandwidth Testing
      3. 5.2.3 Radiation Pattern Measurement
    3. 5.3 MMWAVESTUDIO
      1. 5.3.1 Running LUA Scripts
    4. 5.4 mmWave Visualizer
    5. 5.5 IWR6843ISK-ODS Test Case
  8. 6Common Issues and Resolutions
    1. 6.1 Peak Power
    2. 6.2 Occupied Bandwidth
    3. 6.3 Spurious Emissions
      1. 6.3.1 14.4GHz Harmonics
      2. 6.3.2 Suggested Resolution
        1. 6.3.2.1 Hardware Measures
        2. 6.3.2.2 Software Measures
          1. 6.3.2.2.1 APLL Duty Cycling
          2. 6.3.2.2.2 APLL VCO RTRIM Setting in BSS Firmware
    4. 6.4 Overshoot
    5. 6.5 Frequency Stability
      1. 6.5.1 Generating CW Signal
      2. 6.5.2 Frequency Stability Over Temperature and Voltage Range
    6. 6.6 EIRP Spiking and Spectrum Analyzer BW
  9. 7References
  10. 8Revision History

6.5.2 Frequency Stability Over Temperature and Voltage Range

Problem Statement: Frequency is not within the limit over the temperature and voltage range.

Solution: Adjust the capacitors on the clock to verify approximately 0PPM deviation at room temperature.

Deep Dive: FCC part 15.255, Frequency stability: Fundamental emissions must be contained within the frequency bands specified in this section during all conditions of operation. Equipment is presumed to operate over the temperature range −20℃ to +50℃ with an input voltage variation of 85% to 115% of rated input voltage, unless justification is presented to demonstrate otherwise.

AM72 40MHz Crystal CapacitanceFigure 6-7 40MHz Crystal Capacitance
Equation 17. LoadCapacitor CL=Cf1×Cf2Cf1+Cf2+Cp

where

  • Cp is the parasitic capacitance
  • Cf1 and Cf2 are capacitors in parallel

IWR6843 requires a 40MHz crystal or external oscillator to the CLKP pin; this is used for initial boot up and as reference for the internal APLL and other clocks. For the IWR6843ISK EVM, the crystal is implemented as shown in Figure 6-7. The capacitors are chosen to satisfy requirement shown in Table 6-2.

Table 6-2 Capacitor Requirements
NameDescriptionMinTypMaxUnit
FpParallel resonance crystal frequency40MHz
CLCrystal load capacitance5812pF
Temperature rangeExpected temp range of operation-40105°C
Frequency toleranceCrystal frequency tolerance-5050ppm

To meet the FCC requirements, the capacitors must be tuned such that the oscillator frequency deviation is at 0ppm at room temperature and frequency deviation stays within the frequency band across voltage and temperature .