Transmitter/Receiver/Observation Receiver Signal Chain Calibrations; Initial Calibrations - Analog Devices ADRV9001 User Manual

Reference Manual

TRANSMITTER/RECEIVER/OBSERVATION RECEIVER SIGNAL CHAIN CALIBRATIONS

In the ADRV9001, to achieve optimal performance, an ARM performs calibrations, which are classified into two categories: initial calibrations
performed at initialization before the device is operational and tracking calibrations performed regularly while the device is operational.
Initial calibrations are considered a part of the device initialization, which moves the device from a "STANDBY" state to a "CALIBRATED" state
to prepare for transmit/receive operations. Tracking calibrations are performed regularly on-the-fly while the device is operational to track the
changes such as attenuation/gain, temperature, and so on. The ADRV9001 includes two transmitters and two receivers. For each receiver,
besides acting as a primary data channel for receiving RF signals, it also serves as an observation channel, which receives transmit signals
through loopback paths. The observation channel can be controlled fully by the user or internally controlled by the device for some transmitter
initial and tracking calibrations. Note that for some systems such as FDD 2T2R, the transmitter tracking calibrations requiring loopback paths
are not available. For more details, see the
Most initial calibrations use internally generated tones or wideband signals for calibration, which requires users to satisfy external system
requirements. Later sections discuss this topic in more detail. Different from initial calibrations, tracking calibrations use real-time traffic data
for calibration. Therefore, tracking calibrations are transparent and do not require any user intervention. The ADRV9001 ARM schedules and
performs both initial and tracking calibrations.

INITIAL CALIBRATIONS

There are three types of initial calibrations:
System (non-channel related) initial calibrations
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Initial calibrations for RF PLLs to calibrate the RF PLL for very fast frequency hopping mode
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Aux PLL initial calibration
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Transmitter initial calibrations
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Quadrature error correction (QEC)
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Local oscillator (LO) leakage
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Loop back path delay (LB PD)
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Duty cycle correction (DCC)
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Baseband analog filter (BBAF)
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Baseband analog filter-group delay (BBAF GD)
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Attenuation delay (ATTEN DELAY)
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Digital-to-analog converter (DAC)
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Path delay
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Receiver initial calibrations
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High power ADC resistor/capacitor (HP ADC RC) (reserved, run automatically in analog initialize)
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High power ADC flash offset (HP ADC flash)
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High power ADC DAC (HP ADC DAC) (reserved, not used in ADRV9001)
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Duty cycle correction (DCC)
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Low power ADC (LP ADC)
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TIA cutoff frequency (TIA Cutoff)
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Transimpedance amplifier group delay
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Wideband quadrature error
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Frequency independent quadrature error
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Internal loop back LOD (ILB LOD) (reserved, not used in ADRV9001)
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DC offset (RF DC)
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Gain path delay
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DMR path delay
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Note that the receiver initial calibrations must also be performed on loopback paths to prepare for transmitter initial and tracking calibrations.
To successfully perform all the initial calibrations, configure the ADRV9001 device properly. It is fully controlled by the ADRV9001 ARM.
Therefore, no user interaction is required. However, besides the internal configurations, there are requirements for the external system as
well. For example, during some transmitter initial calibrations, tones are generated and present at the transmitter output. Therefore, ensure
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