NVIDIA Introduces Instant RM for Rapid and Differentiable Radio Maps

Wireless
networks
are
crucial
for
maintaining
seamless
connectivity
across
various
environments,
from
single
buildings
to
entire
cities.
Optimizing
these
networks
often
involves
the
use
of
radio
maps,
which
depict
received
signal
strength
and
other
vital
information
over
large
areas.
Traditionally,
creating
these
maps
has
been
a
time-consuming
task,
limiting
the
effectiveness
of
optimization
methods.
However,
NVIDIA’s
latest
research
project
has
set
a
new
benchmark
by
introducing
Instant
RM,
a
high-performance,
differentiable
ray
tracer.

Differentiable
Radio
Maps
in
an
Instant

NVIDIA
Instant
Radio
Maps
(Instant
RM)
can
compute
high-resolution
radio
maps
at
a
remarkable
rate
of
about
100
maps
per
second.
Leveraging
rendering
techniques
from
high-end
computer
graphics
and
wireless
propagation
models,
Instant
RM
utilizes
NVIDIA
hardware
to
simulate
radio
wave
propagation
in
complex
and
large-scale
environments.

For
instance,
a
coverage
map
shows
the
path
loss
related
to
the
wireless
channel
for
a
given
transmitter,
marked
by
a
blue
dot,
across
a
selected
domain.
Figure
2
illustrates
how
the
number
of
paths
used
to
trace
radio
maps
affects
the
trade-off
between
latency
and
accuracy.
The
images
depict
Paris
near
the
Arc
de
Triomphe
with
an
overlaid
radio
map
displaying
path
loss
using
a
red-yellow
color
gradient.

Advanced
Features
and
Applications

Instant
RM
extends
beyond
path
loss
maps
by
also
supporting:

• Computation
  of
  radio
  maps
  for
  the
  delay
  spread
• Direction
  spread
  of
  departure
  (DSD)
• Direction
  spread
  of
  arrival
  (DSA)

These
advanced
radio
maps
provide
valuable
insights
into
the
characteristics
of
the
wireless
channel.

Instant
RM
requires
only
a
few
lines
of
code
to
load
a
scene
and
compute
radio
maps.
This
ease
of
use,
combined
with
its
high
performance,
makes
it
a
powerful
tool
for
network
optimization.

Enabling
Gradient-Based
Optimization

One
of
the
standout
features
of
Instant
RM
is
its
fully
differentiable
ray
tracer.
This
capability
allows
for
the
computation
of
gradients
of
functions
of
the
radio
maps
concerning
material
properties
and
scene
geometry.
An
intriguing
application
is
the
gradient-based
calibration
of
a
propagation
environment
from
measurements,
ensuring
that
simulation
results
align
with
real-world
observations.

Differentiable
ray
tracing
facilitates
gradient-based
network
optimization
at
unprecedented
speeds.
For
example,
in
one
animation,
the
shape
of
a
reflector
is
optimized
to
maximize
the
signal-to-interference
ratio
on
the
radio
map.

Getting
Started
with
Instant
RM

To
begin
using
Instant
RM,
follow
the
README
instructions
available
on
the

GitHub
repository.
The
source
code
and
a
detailed
tutorial, “Hello,
Instant
RM!”,
are
accessible
to
the
research
community,
showcasing
the
tool’s
features
in
an
interactive
notebook.

For
more
detailed
information,
refer
to
the

NVIDIA
Technical
Blog.

Image
source:
Shutterstock