mmWave Design
the rapid adoption of mmWave radar in
future ADAS enabled cars and trucks.
To manage the adoption of these
technologies, radar developers require
RF-aware system design software that
supports radar simulations with detailed
analysis of RF front-end components,
including nonlinear RF chains, advanced
antenna design, and channel modeling.
Co-simulation with circuit and
electromagnetic (EM) analysis provides
accurate representation of true system
performance prior to building and testing
costly radar prototypes. NI AWR
software provides these capabilities, all
within a platform that manages automotive
radar product development— from
initial architecture and modulation studies
through the physical design of the
antenna array and front-end electronics
based on either III-V or silicon integrated
circuit (IC) technologies.
The NI AWR Design Environment
platform integrates these critical radar
simulation technologies while providing
the necessary automation to assist the
engineering team with the very complex
task of managing the physical and electrical
design data associated with ADAS
electronics. ADAS support includes:
• Design of waveforms, baseband signal
processing, and parameter estimation
for radar systems, with specific analyses
for radar measurements along with
comprehensive behavioral models for
RF components and signal processing.
• Design of transceiver RF/MW front-end
with circuit-level analyses and modeling
(distributed transmission lines and
active and passive devices) to address
printed circuit board (PCB) and
monolithic microwave IC (MMIC)/RFIC
design.
• Planar/3D EM analysis for characterizing
the electrical behavior of passive
structures, complex interconnects,
and housings, as well as antennas and
antenna arrays.
• The connection between simulation
software and test and measurement
instruments.
RADAR ARCHITECTURES AND
MODULATION
For adaptive cruise control (ACC),
simultaneous target range and velocity
measurements require both high resolution
and accuracy to manage multitarget
scenarios such as highway traffic.
Future developments targeting safety
applications like collision avoidance
(CA) or autonomous driving (AD) call for
even greater reliability (extreme low false
alarm rate) and significantly faster reaction
Figure 2: Multiple frequency shift keying.
Figure 3: Pulsed-Doppler radar example in VSS.
Figure 4: RF transmitter block is based on a sub-circuit containing filtering,
amplifier, and frequency converter.
times compared to current ACC systems,
which utilize relatively well-known
waveforms with long measurement times
(50-100 ms).
Important requirements for automotive
radar systems include the maximum
range of approximately 200 m for ACC,
a range resolution of about 1 m and a
velocity resolution of 2.5 km/h. To meet
all these system requirements, various
waveform modulation techniques and
architectures have been implemented,
including a continuous wave (CW) transmit
signal or a classical pulsed waveform
with ultra-short pulse length.
The main advantages of CW radar systems
in comparison with pulsed waveforms
are the relatively low measurement
time and computation complexity for a
fixed high-range resolution system requirement.
The two classes of CW waveforms
widely reported in literature include
linear-frequency modulation (LFMCW)
and frequency-shift keying (FSK), which
use at least two different discrete transmit
frequencies. Table 1 compares the different
radar architectures and their advantages
and disadvantages.
For ACC applications, simultaneous
range and relative velocity are of the
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