SWRZ072B May   2017  – December 2020 AWR1642

 

  1. 1Introduction
  2. 2Device Nomenclature
  3. 3Device Markings
  4. 4Usage Notes
    1. 4.1 MSS: SPI Speed in 3-Wire Mode Usage Note
  5. 5Advisory to Silicon Variant / Revision Map
  6. 6Known Design Exceptions to Functional Specifications
    1.     MSS#10
    2.     MSS#11
    3.     MSS#12
    4.     MSS#14
    5.     MSS#16
    6.     MSS#17
    7.     MSS#18
    8.     MSS#19
    9.     MSS#20
    10.     MSS#22
    11.     MSS#37B
    12.     MSS#38A
    13.     MSS#39
    14.     MSS#40
    15.     MSS#42
    16.     MSS#43
    17.     MSS#44
    18.     MSS#45
    19.     ANA#06
    20.     ANA#08A
    21.     ANA#09A
    22.     ANA#10A
    23.     ANA#11A
    24.     ANA#12A
    25.     ANA#15
    26.     ANA#16
    27.     ANA#17A
    28.     ANA#18B
    29.     ANA#20
    30.     ANA#21A
    31.     ANA#22A
    32.     ANA#24A
    33.     ANA#27
    34.     DSS#01
    35.     DSS#02
    36.     DSS#03
    37.     DSS#04
    38.     DSS#05
    39.     DSS#06
    40.     DSS#07
  7. 7Trademarks
  8. 8Revision History

ANA#08A

Doppler Spur Observed at Certain RF Frequencies

Revision(s) Affected:

AWR1642 ES1.0 and AWR1642 ES2.0

Description:

When the instantaneous FMCW Ramp frequency nears certain specific RF frequencies, there can be coupling between the synthesizer's reference and its output, and manifest as frequency glitches or spurs in TX output spectrum.

Implication: In FMCW radar 2D signal processing, this can lead to spurs in a fixed Doppler bin at all range bins. This situation can occur with narrow band chirps, if the FMCW ramp includes or nears 76.8-, 77.4-, 78-, 79.2-, 80.4-, 81-GHz RF frequencies. The affected Doppler bin is a function of chirp timing and RF frequency properties.

Workaround(s):

Use the device's dithering features to vary idle time, RF frequency and ramp end times to spread the spurs significantly in Doppler dimension so that it does not get detected as spurious targets. Using larger chirp band widths also reduces the spur level.