SPRACF4C June   2018  – January 2023 AWR1243 , AWR1443 , AWR1642 , AWR1843 , AWR1843AOP , AWR2243 , AWR6843 , AWR6843AOP , IWR1843 , IWR6443 , IWR6843 , IWR6843AOP

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Purpose of Calibrations
    2. 1.2 Purpose of Monitoring Mechanisms
  3. 2Hardware Infrastructure to Support Calibration and Monitoring
  4. 3List of Calibrations
    1. 3.1  APLL Calibration
    2. 3.2  Synthesizer VCO Calibration
    3. 3.3  LO Distribution Calibration
    4. 3.4  ADC DC Offset Calibration
    5. 3.5  HPF Cutoff Calibration
    6. 3.6  LPF Cutoff Calibration
    7. 3.7  Peak Detector Calibration
    8. 3.8  TX Power Calibration
    9. 3.9  RX Gain Calibration
    10. 3.10 IQ Mismatch Calibration
    11. 3.11 TX Phase Shifter Calibration
  5. 4Impact of Calibration on Gain and Phase
  6. 5Impact of Interference on the Calibrations and Emissions Caused Due to Calibrations
  7. 6Scheduling of Runtime Calibration and Monitoring
    1. 6.1 Selection of CALIB_MON_TIME_UNIT
    2. 6.2 Selection of CALIBRATION_PERIODICITY
    3. 6.3 Application-Controlled One Time Calibration
  8. 7Software Controllability of Calibration
    1. 7.1  Calibration and Monitoring Frequency Limits
    2. 7.2  Calibration and Monitoring TX Frequency and Power Limit
    3. 7.3  Calibration Status Reports
      1. 7.3.1 RF Initialization Calibration Completion
      2. 7.3.2 Runtime Calibration Status Report
      3. 7.3.3 Calibration/Monitoring Timing Failure Status Report
    4. 7.4  Programming CAL_MON_TIME_UNIT
    5. 7.5  Calibration Periodicity
    6. 7.6  RF Initialization Calibration
    7. 7.7  Runtime Calibration
    8. 7.8  Overriding the TX Power Calibration LUT
    9. 7.9  Overriding the RX Gain Calibration LUT
    10. 7.10 Retrieving and Restoring Calibration Data
  9. 8References
  10.   A Calibration and Monitoring Durations
    1.     A.1 Duration of Boot Time Calibrations
  11.   Revision History

6 Scheduling of Runtime Calibration and Monitoring

The device receives the desired chirp and frame configuration from the corresponding API messages, and schedules transmission of chirps accordingly. Chirps are transmitted in bursts or frames, as per the configuration programmed.

All periodic calibrations and monitoring are scheduled by the device in the large inter-frame (or inter-burst, for advanced frames) idle time periods in every frame. Run time calibrations in One Time mode must scheduled and triggered manually by the application based on the internal temperature sensor reading. They must trigger a frame prior to the frame where the change is intended. Individual monitors and calibrations can be enabled or disabled as needed in the application. The periodicity of calibration and monitoring is configurable by two programmable parameters: CALIB_MON_TIME_UNIT and CALIBRATION_PERIODICITY.

One cycle of monitoring covering all enabled monitors is carried out every CALIB_MON_TIME_UNIT frames, (as programmed by the user). Therefore:

Equation 1. MonitoringPeriod (in µs) = FramePeriod (in µs) × CALIB_MON_TIME_UNIT

Periodic calibrations (except APLL and Synthesizer VCO calibrations) are carried out at a configurable multiple of CALIB_MON_TIME_UNIT. This multiple is configured using the CALIBRATION_PERIODICITY parameter.

Equation 2. CalibrationPeriodicity (in µs) = MonitoringPeriod (in µs) × CALIBRATION_PERIODICITY
Note:

APLL and Synthesizer VCO calibrations are always carried out in the next available idle period after every 1 second; this is not controllable by the host. APLL and Synthesizer VCO calibrations are always enabled. The CALIB_MON_TIME_UNIT should be set to ensure the monitoring period is within the range mentioned in the Interface Control Document, even if no monitors are enabled. This is to necessary to ensure successful APLL and Synth periodic calibration.

The value of CALIB_MON_TIME_UNIT must be large enough to accommodate all enabled monitors, all enabled periodic runtime calibrations and some software overheads. Even though calibration may not necessarily be carried out in every monitoring period, it must still be budgeted for when selecting CALIB_MON_TIME_UNIT.

Every CALIBRATION_PERIODICITY, the processor reads the temperature and performs a calibration update if needed. This update is done only if the temperature deviates by ±10 degrees compared to the temperature when the last calibration was done.

This temperature measurement and calibration happens during the idle time between frames (or bursts). If any calibration results in an update to the device registers, the host is notified about the calibration update through an asynchronous event message.

The device determines the available idle time before the start of each frame (or burst) to ensure that there is enough idle time to complete each calibration.

Figure 6-1 shows an example where CALIB_MON_TIME_UNIT is 2 and CALIBRATION_PERIODICITY is 3. Note that monitoring activity can be spread across several inter-frame idle times. For detailed examples on programming CALIB_MON_TIME_UNIT and CALIBRATION_PERIODCITY, refer to the Interface Control Document in the mmave DFP.

GUID-3C165902-E65B-423B-9A70-0C79E761FD69-low.pngFigure 6-1 Calibration and Monitoring Activity During Inter-Frame Idle Times