SpaceX is currently hiring for a number of open positions in the
Avionics -
RF group, including:
RF & Comms Systems Engineering
RF Design engineers (RF/hardware/digital)
MAC Layer Engineers
Antenna Engineers
anyone else who is just a rock star
GNU Radio, general SDR, and FPGA targetting experience is a major plus.
The environment is one of the more demanding you’ll find, but the work
is
extremely rewarding. Benefits are pretty awesome too. Let me know if
you
are interested and would like to discuss.
In the meantime, here’s some of the ambitious things we aee working on:
Full-Software ETSI DVB-T Transmitter over Intel Atom N270
This is an ETSI DVB-T transmitter (the sort of thing that sends digital
TV
into our homes throughout Europe and in many other countries across the
Globe) implemented on an ultra-small, ultra-weak Intel Atom CPU. I built
it
in the early days of my PhD.
Full-Software ETSI DVB-T Single Frequency Network on a Tabletop
These are two of those transmitters, in a synced transmit-network
config.
Full-software ETSI DVB-T Receiver
Implementing from scratch these systems exposed me to transmission and
channel coding techniques which, in the DVB-T rev.1 case, do precisely
come
from deep space transmission experiences dating back to the 80s (Voyager
II) and reaching far into the late 90s. DVB-T2 stuff includes instead
more
recent codes (LDPCs) that are currently being tested and standardized by
the CCSDS, for adoption by upcoming missions (I believe, eventually,
even
for actual deep-space contexts).
I’m highly interested in energy-efficient, energy-limited radio
transmission systems (a.k.a. the most peculiar deep space comm
requirement
set).
After earning my PhD, and moving to my current company ( www.idscorporation.com), I led the development of a few SDR systems,
including this:
IDS – GNOME system: an SDR-based GNSS integrity monitor
(it was actually presented and (partially) demoed @NAVITEC '12 in ESTEC)
and a ground receiver for ADS-B air traffic control signals. It’s not
that
much of a relevant job (ADS-B radios are simple and --believe it or
not–
almost uncoded) but we were very quick in getting the receiver done
thanks
to the flexibility of the SDR concepts.
As to recent research, together with a bunch of colleagues, I worked on
a
PHY-layer crypto concept called “directional modulation” in which I see
some potentially significant SatCom applicability.
Directional Modulation is something that restricts access to information
in
certain (controllable) regions of the space surrounding the transmitting
antenna. It does so by taking into account the spatial propagation of
the
radio signal and applying, based on such info, a multiplicative
distortion
process to the transmitted signal, that can (if suitably designed)
render
the transmitted info interdicted (and actually cryptographically secure)
in
unwanted regions of the space while leaving it unaltered elsewhere. It’s
not a replacement for traditional crypto but, i believe, it’s a powerful
complement to it.
With respect to previous literature in the field, which only applied the
concept to legacy, very simple radio systems, we devised and
demonstrated a
way of putting it on top of state of art radio-transmission systems such
as
ETSI DVB-T1 & T2. Application to the satellite case (namely DVB-S 1 & 2)
has no roadblocks.
The relevant article for the job that was carried out is here:
Still, within IDS, I led the spec. design and set up the testing
procedures
for the radio subsystems (both payload downlink radios and C2 radios. C2
in
UAV systems ~= TT&C in spacecom) of our SD-150 HeRo UAV, which is this
thing here:
currently being in a quite advanced development phase and looking
forward
to its “maiden flight”.
I’m currently managing iterations with providers of the radio subsystem
components to bring the whole thing as close as possible to our target
spec. We’re almost there, even if not exactly there yet.
I’m also taking care of some design issues for a set of smaller UAVs
that
the company is currently bringing to market.
Here SWaP constraints are what makes the job more difficult and relevant
to
some extent, even if radiocom requirements are quite a bit relaxed wrt
the
former (150 kg MTOW) case.
If this background is of some interest for SpaceX. I’m looking forward
to
discussing it in detail.
