ADF4158 datasheet(32/36 Pages) AD

32 / 36 page

ADF4158

Rev. 0 | Page 32 of 36

APPLICATION OF ADF4158 IN FMCW RADAR

The application of ADF4158 in FMCW radar is shown in

Figure 45.

LINEAR

FREQUENCY

SWEEP

NO DDS REQUIRED

WITH ADF4158

REFERENCE

OSCILLATOR

26MHz

VCO

ADF4158

PLL

×5

MULTIPLY

×15

×3

ANTENNA

ANTENNAS

76.5GHz

77.0GHz

5.1GHz

5.1333GHz

MICRO-

CONTROLLER

16B

10B

12B

BUS

CAN/FLEXRAY

RANGE

COMPENSATION

BASEBAND

MIXER

DSP

ADSP-BF531

AD9288

AD9235

MUX

ADC

HPF

Figure 45. FMCW Radar with ADF4158

The ADF4158 in FMCW radar is used for generating ramps

(sawtooth or triangle) that are necessary for this type of radar

to operate. Traditionally, the PLL was driven directly by a direct

digital synthesizer (DDS) to generate the required type of wave-

form. Due to the implemented waveform generating mechanism

on the ADF4158, a DDS is no longer needed, which reduces cost.

In addition, the PLL solution has advantages over another

method (the DAC driving the VCO directly) for generating

FMCW ramps, which suffered from VCO tuning characteristics

nonlinearities requiring compensation. The PLL method

gives highly linear ramps without the need for calibration.

ADF4158 Datasheet(PDF) 32 Page - Analog Devices

ADF4158 Datasheet(HTML) 32 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

Datasheet Download

Link URL